WEBVTT

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Welcome to The Deep Dive, the show where we really

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get into the sources, the research, the articles,

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the notes, to bring you the essential insights,

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maybe some surprising facts, and enough context

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so you feel properly informed, but not swamped

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in technical terms. Exactly. Today, we are tackling

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something that crops up far too often, particularly

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if you're involved in sports in any way, injuries

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to the anterior cruciate ligament, that infamous

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ACL tear. It's a really significant problem,

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actually, and quite complex when you look closely.

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The sources we've drawn on top, orthopedic resources

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like orthobullets, ortho info, stat pearls, the

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bone school, they give us a pretty detailed picture

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from the tiny fibers of the ligament itself right

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through to the... Well, often long road to recovery.

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Absolutely. So our aim here is to guide you,

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our listener, through what these resources tell

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us about ACL injuries. We'll look at what the

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ACL actually is, how these tears usually happen,

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how doctors work out what's gone wrong, the treatment

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choices, what recovery involves, and, well, the

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potential bumps in the road. It's a proper deep

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dive into a major knee issue. Right. Let's get

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started then. See what the sources lay out for

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us. Okay, starting right at the beginning. When

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we talk about the ACL, what exactly is it? Whereabouts

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in the knee does it live and what's its job?

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We know the knee is where those big leg bones

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meet, don't we? That's the place to start, yes.

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The knee joint is essentially where three bones

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come together. You've got the femur, the thigh

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bone coming down, the tibia, the shin bone below

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it, and then the patella. the kneecap sitting

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at the front there. And holding these together,

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giving stability, are strong bands called ligaments.

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Think of them like, well, really tough ropes.

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Ropes providing stability. OK. And the knee relies

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on several of these. It does. Four main ones.

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You've got the collateral ligaments running down

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the sides, the medial collateral, the MCL on

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the inside, and the lateral collateral, the LCL

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on the outside. They primarily stop the knee

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bending sideways, buckling inwards or outwards.

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Got it. Side to side stability from those. And

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then there are the ones inside the joint crossing

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over. Precisely. Those are the cruciate ligaments.

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They form an X shape right in the center of the

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knee. There's the posterior cruciate ligament,

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the PCL, towards the back, and the anterior cruciate

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ligament, the ACL, at the front. And these two

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are really crucial for controlling the forward

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and backward movement of the tibia relative to

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the femur. And our focus today, the ACL. Where

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is it within that X and what are its main functions

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according to these sources? So the ACL runs diagonally

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right through the middle of that joint space.

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Its role is absolutely fundamental for knee stability.

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The sources really flag up two key jobs. First,

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stopping the tibia from sliding too far forward

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relative to the femur. Alright, that forward

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slide. And second, providing rotational stability.

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That's vital for any twisting, pivoting, changing

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direction type movements. It's not huge, actually

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usually about 32 millimeters long, maybe 7 to

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12 millimeters wide. So it's not just stopping

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that shin bone shifting forwards, but also controlling

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the twisting. That rotational part sounds critical

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for anything dynamic. Oh, absolutely, it's crucial.

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And the sources, they actually break the ACL

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down further. They talk about its two main parts,

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or bundles, the andromedial bundle, the AM, and

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the post -relateral bundle, the PL. two parts

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doing slightly different jobs. Tell me more about

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that. Yes, they have subtly different roles and

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they get tight at different points in the knees

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movement. The AM bundle is described as being

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more isometric, meaning its length doesn't change

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that much as the knee bends and straightens.

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It's tightest when the knee is bent in flexion.

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Okay. Its main job is resisting that straightforward

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movement of the tibia. It gives about 85 % of

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that anterior stability. The main stabilizer

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for forward movement? Largely, yes. The PL bundle,

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on the other hand, changes length more. It's

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tightest when the knee is straight in extension,

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and it's primarily responsible for controlling

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that rotational stability we mentioned. That's

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fascinating. So perhaps if someone has a partial

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tear, which bundle is affected could influence

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the specific type of instability they feel? That's

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exactly right. Although it's worth noting, the

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sources say most ACL injuries are complete or

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very near complete tears. But partial tears do

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happen. The ligament itself, it's mostly type

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I collagen that gives it its strength. It gets

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blood supply from the middle geniculate artery

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and has some nerve endings too. It's remarkably

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strong. Actually, it can withstand forces around

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2200 Newtons. That sounds like a lot. It is significant,

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yes. But clearly, under certain conditions, particularly

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in sports, the phosis can exceed that. Right,

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which brings us neatly to the next point. How

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does this strong ligament actually get torn?

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What are the typical scenarios that lead to an

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ACL injury? The sources are very consistent here.

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The most common mechanism by far is what's known

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as a non -contact pivoting injury. Non -contact,

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so it doesn't have to involve a collision or

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being tackled. Correct. In most cases, no one

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touches the person. It usually happens when the

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food is firmly planted on the ground and the

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body twists or pivots forcefully over the slightly

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bent knee. Often, the knee collapses inwards

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what we call a valgus position. Ah, I can picture

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that. The foot stays put, the body turns, and

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the knee caves in. Precisely. The tibia is essentially

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forced forwards relative to the femur, often

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with that twisting element, and the ACL just

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can't handle that load. That valgus collapse

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seems to be a recurring theme in sports injuries.

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It is indeed. Other common non -contact ways

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it can happen include stopping very suddenly

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when running, slowing down rapidly, or landing

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awkwardly from a jump. Direct contact, like a

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tackle in rugby or football, can definitely cause

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an ACL tear too, often along with other ligament

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damage, but it's less frequent than the non -contact

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type. And certain sports are just inherently

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riskier because they involve these movements

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constantly. Absolutely. Sports like football,

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basketball, skiing, netball, they're frequently

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mentioned because they demand so many rapid changes

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of direction. Cutting maneuvers, jumping, landing,

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sudden stops. The courses also suggest the rise

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in ACL injuries might be partly linked to more

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people participating in high level high -intensity

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sports. OK, so that non -contact pivot is the

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primary culprit. Now let's think about who gets

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these injuries. Is it mainly professional athletes?

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Well, it's surprisingly common across the active

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population, not just pros. The sources quote

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figures like around 400 ,000 ACL reconstructions

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happening each year in the U .S. alone. They

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actually account for about half of all knee injuries

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treated surgically. The overall rate is about

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1 in 3 ,500 people per year in the U .S. Wow,

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that's a lot. It is. And while it can happen

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to anyone, any age, the sources consistently

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highlight a much higher incidence among female

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athletes. That's a really important point. Female

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athletes are often cited as being more susceptible.

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What sort of difference are we talking about

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and what reasons do the sources give? The ratio

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mentioned is quite stark. Roughly 4 .5 female

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athletes injure their ACL for every one male

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athlete playing similar sports, so a significantly

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higher risk. Four and a half times higher. That's

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huge. It is. And interestingly, the sources also

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mention female athletes tend to get these injuries

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younger, and often it's the supporting leg that

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goes, whereas males might more often injure their

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kicking leg. Okay, so why? What's behind this

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disparity? What factors contribute to female

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athletes being at greater risk? The sources suggest

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it's not one single thing, but rather a combination

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of factors. It's multifactorial. They point to

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differences in physical conditioning, overall

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muscle strength, and perhaps crucially, neuromuscular

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control. Neuromuscular control? Can you unpack

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that a bit? What does that mean in this context?

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It's essentially how the brain coordinates muscle

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activity during movement, particularly during

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dynamic actions like landing from a jump or quickly

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changing direction. The sources suggest female

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athletes may be more prone to landing or cutting

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with increased valgus at the knee. That inward

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collapse we mentioned potentially combined with

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less bending at the hip and knee to absorb the

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shock. So the way they land and move puts more

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stress on the knee joint itself. Potentially,

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yes. They might also exhibit this valgus pattern

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more when fatigued, possibly due to differences

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in muscle fatigue resistance. Another key point

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raised is about muscle activation patterns. Some

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research suggests female athletes can be more

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quadriceps dominant. Meaning they rely more on

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the front thigh muscles? Exactly. They might

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engage their quads more heavily during deceleration

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or landing. The issue is, the hamstrings, the

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muscles at the back of the thigh, are actually

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more effective at preventing the tibia from sliding

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forward, which is what protects the ACL. Over

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reliance on the quads during these movements

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might place abnormal stress on the ligament.

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Weaker core stability compared to males is also

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sometimes mentioned, as it affects overall control.

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OK, so it's about how the muscles fire and control

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movement and how forces are absorbed. Are there

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physical or anatomical differences discussed

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too? Yes, anatomical factors are also suggested

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as potential contributors, though these are obviously

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less easy to modify. Things like ERM, possibly

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increased BMI, having a narrower space in the

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femur where the ACL sits the femoral notch. perhaps

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a smaller ACL ligament overall or greater general

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joint flexibility or laxity. And wasn't there

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mention of hormones as well? Yes, the sources

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do touch upon potential hormonal influences,

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but they are careful to state this is still a

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somewhat controversial area without definitive

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proof. The idea is that fluctuations in hormones

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like estrogen might affect the properties of

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ligaments. There's also a suggestion that coordination

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could be subtly affected during certain phases

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of the menstrual cycle, like the pre -ovulatory

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phase. Interestingly, one study noted athletes

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using oral contraceptives seemed less affected,

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but again, it's complex. So, a potential factor,

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but the jury's still out on the exact role of

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hormones. Anything else that increases risk?

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Genetics might play a part. Variations in genes

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related to collagen, like COO5A1, have been linked

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to injury risk. And other general risk factors

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include having had a previous concussion, which

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could affect balance and reaction times, and

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unsurprisingly, having had a previous ACL injury

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on either knee significantly raises your risk

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of having another one. That's a really thorough

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overview of the risk factors, showing just how

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complex this issue is, particularly for female

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athletes. Now, when the ACL does tear, it often

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doesn't happen in isolation, does it? Other structures

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in the knee frequently get damaged simultaneously.

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That's a critical point the sources emphasize.

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About half of all ACL tears involve damage to

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other parts of the knee as well. In acute injuries,

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meaning recent ones, damage to the lateral meniscus,

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the cartilage on the outside of the knee is very

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common. One source puts it at 54 % of cases.

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Over half. Yes. And injuries to the PCL, the

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LCL, or the structures in the back outer corner

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of the knee, the post -relateral corner, can

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also occur at the same time. And what happens

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if an ACL tear isn't addressed, if the knee remains

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unstable over the long term? The sources are

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quite clear on this. A knee that's chronically

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deficient in its ACL is highly prone to progressive

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damage. This often involves chondral injuries

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damaged to the smooth, articular cartilage that

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lines the joint surfaces and more complex meniscal

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tears developing over time. Things like those

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difficult -to -repair bucket -handle tears of

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the medial meniscus become more common in chronically

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unstable knees. So living with that instability

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isn't just inconvenient, it actually increases

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the risk of more permanent joint damage down

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the line. Precisely. It significantly increases

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the risk of developing further problems, including

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the earlier onset of osteoarthritis. That really

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underlines why getting a proper diagnosis and

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appropriate management is so important. Okay,

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let's switch focus now to actually recognizing

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and diagnosing an ACL tear. What does it typically

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feel like for the person at the moment it happens?

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The sources paint a pretty consistent picture

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of the immediate experience. A very common report

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is hearing or feeling a sudden, distinct pop

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sound or sensation from within the knee right

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at the moment of injury. The classic pop. I often

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hear about that. Yes, it's mentioned frequently.

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After the pop, patients often describe a feeling

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of the knee instantly giving way or buckling

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under them. Then comes the pain, usually felt

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deep inside the joint. In the majority cases

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around 70%, according to one source, there's

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significant and rapid swelling. Why does it swell

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up so quickly? That's due to bleeding inside

00:12:23.870 --> 00:12:26.690
the joint from the torn ligament fibers. It's

00:12:26.690 --> 00:12:29.370
called hemarthrosis. It's a strong sign that

00:12:29.370 --> 00:12:31.169
a significant injury has occurred within the

00:12:31.169 --> 00:12:33.490
joint capsule. Other common symptoms include

00:12:33.490 --> 00:12:35.669
difficulty putting weight on the leg, a more

00:12:35.669 --> 00:12:37.789
general ache around the knee, that persistent

00:12:37.789 --> 00:12:40.230
feeling of instability, especially when trying

00:12:40.230 --> 00:12:42.929
to cut or pivot loss of the full range of knee

00:12:42.929 --> 00:12:45.710
movement, and tenderness if you press along the

00:12:45.710 --> 00:12:48.759
joint line. OK, so that combination. Pop. giving

00:12:48.759 --> 00:12:51.240
way, pain, and fast swelling. Those are the big

00:12:51.240 --> 00:12:53.899
initial clues. But I've heard sometimes the initial

00:12:53.899 --> 00:12:56.100
pain and swelling can actually subside after

00:12:56.100 --> 00:12:58.879
a while. They can, yes, and this is a really

00:12:58.879 --> 00:13:01.340
crucial point the sources make. The acute pain

00:13:01.340 --> 00:13:03.320
and swelling might settle down after a few days

00:13:03.320 --> 00:13:07.159
or weeks, especially with rest. However, the

00:13:07.159 --> 00:13:09.240
underlying mechanical problem, the instability

00:13:09.240 --> 00:13:12.000
from the torn ligament, is still there. If the

00:13:12.000 --> 00:13:14.960
person then tries to return to sports or activities

00:13:14.960 --> 00:13:17.879
involving cutting and pivoting, the knee is very

00:13:17.879 --> 00:13:20.720
likely to feel unstable and give way again. And

00:13:20.720 --> 00:13:22.700
it's these repeated episodes of instability,

00:13:22.779 --> 00:13:25.539
this buckling, that puts the meniscus and the

00:13:25.539 --> 00:13:28.200
articular cartilage at such high risk of further

00:13:28.200 --> 00:13:30.100
damage that progressive wear and tear we talked

00:13:30.100 --> 00:13:32.580
about. So even if it feels a bit better, the

00:13:32.580 --> 00:13:35.059
instability remains, potentially causing more

00:13:35.059 --> 00:13:37.279
harm over time if you try to push through it.

00:13:37.740 --> 00:13:40.580
Got it. How do doctors then confirm it is an

00:13:40.580 --> 00:13:43.059
ACL tear and figure out the full picture of the

00:13:43.059 --> 00:13:45.600
damage? The diagnostic process really starts

00:13:45.600 --> 00:13:47.720
with listening carefully to the patient's story.

00:13:48.090 --> 00:13:50.629
How exactly did the injury happen? What did they

00:13:50.629 --> 00:13:53.009
feel? Could they walk afterwards? That history

00:13:53.009 --> 00:13:55.929
is key. Then comes a physical examination, which

00:13:55.929 --> 00:13:58.429
is absolutely vital. And comparing to the good

00:13:58.429 --> 00:14:01.889
knee is important, always. Comparing the injured

00:14:01.889 --> 00:14:04.669
knee to the uninjured one is essential to establish

00:14:04.669 --> 00:14:07.850
the person's baseline level of laxity, as everyone's

00:14:07.850 --> 00:14:11.009
different. Doctors will look for swelling, check

00:14:11.009 --> 00:14:13.330
for things like a quadriceps avoidance gait,

00:14:13.450 --> 00:14:15.789
where the patient subconsciously avoids fully

00:14:15.789 --> 00:14:18.289
straightening the knee and assess for any pre

00:14:18.289 --> 00:14:21.090
-existing alignment issues. They'll also perform

00:14:21.090 --> 00:14:24.309
specific tests for associated injuries like meniscal

00:14:24.309 --> 00:14:27.389
tears or damage to other ligaments. A lack of

00:14:27.389 --> 00:14:29.330
full knee extension is a particularly important

00:14:29.330 --> 00:14:31.629
finding as it might signal a trapped piece of

00:14:31.629 --> 00:14:33.950
meniscus or early stiffness setting in. And there

00:14:33.950 --> 00:14:36.549
are those specific hands -on tests for the ACL

00:14:36.549 --> 00:14:39.009
itself, provocative tests. Which ones are the

00:14:39.009 --> 00:14:41.549
mainstays? Yes. The Lackmann's test is widely

00:14:41.549 --> 00:14:43.629
considered one of the most sensitive and reliable

00:14:43.629 --> 00:14:46.330
tests, especially soon after the entry. How does

00:14:46.330 --> 00:14:48.460
that one work? The examiner has the patient lying

00:14:48.460 --> 00:14:51.320
down, knee bent slightly, usually around 30 degrees.

00:14:51.940 --> 00:14:54.039
They stabilize the thigh bone with one hand and

00:14:54.039 --> 00:14:56.080
gently pull the shin bone forward with the other.

00:14:56.639 --> 00:14:58.799
In an ACL tear, you'll often feel the shin bone

00:14:58.799 --> 00:15:00.940
move forward more than on the uninjured side.

00:15:01.480 --> 00:15:03.759
And crucially, you won't feel a distinct, firm

00:15:03.759 --> 00:15:06.559
stop, what we call the endpoint. It feels sort

00:15:06.559 --> 00:15:09.360
of mushy or empty. Looking for that excessive

00:15:09.360 --> 00:15:12.230
forward slide and the lack of a solid stop. Exactly.

00:15:12.690 --> 00:15:15.110
The sources give it high accuracy ratings, around

00:15:15.110 --> 00:15:19.289
95 % sensitivity and 94 % specificity. The amount

00:15:19.289 --> 00:15:21.830
of forward movement helps grade the tear, and

00:15:21.830 --> 00:15:24.269
comparing sides is absolutely key. Makes sense.

00:15:24.370 --> 00:15:26.450
What about the anterior drawer test? Is that

00:15:26.450 --> 00:15:28.769
similar? It's another common one, yes. For this,

00:15:28.870 --> 00:15:31.110
the knee is bent more to 90 degrees, usually

00:15:31.110 --> 00:15:33.409
with the foot resting flat. The examiner sits

00:15:33.409 --> 00:15:35.049
lightly on the foot and pulls the top of the

00:15:35.049 --> 00:15:37.690
shin bone forward. Again, excessive forward movement

00:15:37.690 --> 00:15:39.950
compared to the other side suggests an ACL tear.

00:15:40.610 --> 00:15:43.190
Interestingly, the sources note this test is

00:15:43.190 --> 00:15:46.029
often more reliable or easier to interpret in

00:15:46.029 --> 00:15:48.850
chronic ACL tears, perhaps when the initial pain

00:15:48.850 --> 00:15:52.049
and muscle spasm have subsided. Right, so Lachman's

00:15:52.049 --> 00:15:54.570
may be better acutely, anterior drawer potentially

00:15:54.570 --> 00:15:57.429
more obvious later on, and the pivot shift test.

00:15:57.909 --> 00:15:59.830
That sounds like it's deliberately trying to

00:15:59.830 --> 00:16:02.629
make the knee feel unstable. It is, in a controlled

00:16:02.629 --> 00:16:06.230
way. It aims to replicate that giving way sensation

00:16:06.230 --> 00:16:08.990
the patient might describe. The examiner takes

00:16:08.990 --> 00:16:11.129
the knee from a straight position, applying a

00:16:11.129 --> 00:16:13.690
bit of inward pressure, valgus, and internal

00:16:13.690 --> 00:16:16.110
rotation to the lower leg and then bends the

00:16:16.110 --> 00:16:19.250
knee. If the ACL is torn, the tibia might start

00:16:19.250 --> 00:16:21.350
slightly forward when straight and then noticeably

00:16:21.350 --> 00:16:23.769
clunk or shift back into place as the knee bends

00:16:23.769 --> 00:16:26.070
to around 20 -30 degrees. So you're basically

00:16:26.070 --> 00:16:28.190
inducing that little subluxation and reduction

00:16:28.190 --> 00:16:30.990
to see if it happens. That's the idea. However,

00:16:31.470 --> 00:16:33.649
it can be quite difficult to get a positive pivot

00:16:33.649 --> 00:16:36.350
shift test in someone who's awake and apprehensive

00:16:36.350 --> 00:16:38.830
or in pain, as muscle guarding can prevent the

00:16:38.830 --> 00:16:42.110
shift. It's often much easier to demonstrate

00:16:42.110 --> 00:16:44.909
under anesthesia when the muscles are fully relaxed.

00:16:45.490 --> 00:16:47.350
Because of this, the sources say it's highly

00:16:47.350 --> 00:16:50.269
specific if you get a positive test, it's almost

00:16:50.269 --> 00:16:53.529
certainly an ACL tear, 98 % specificity, but

00:16:53.529 --> 00:16:56.389
not very sensitive, maybe only 24 % in the clinic,

00:16:56.690 --> 00:16:58.649
because it's often negative even when a tear

00:16:58.649 --> 00:17:01.159
is present. That explains why it's not always

00:17:01.159 --> 00:17:03.539
positive, even with a definite tear. Are there

00:17:03.539 --> 00:17:06.140
any other, maybe simpler, tests mentioned? Yes,

00:17:06.240 --> 00:17:08.680
the sources mention the lever sign test. The

00:17:08.680 --> 00:17:10.359
examiner puts their fist under the patient's

00:17:10.359 --> 00:17:13.559
upper calf and pushes down on the thigh. If the

00:17:13.559 --> 00:17:15.779
ACL is intact, the heel should lift off the couch.

00:17:16.099 --> 00:17:18.920
If it's torn, the heel tends to stay down. There

00:17:18.920 --> 00:17:21.579
are also devices, like the KT1000 Arthrometer,

00:17:21.920 --> 00:17:24.160
which can provide an objective measurement of

00:17:24.160 --> 00:17:26.579
that anterior tibial translation, quantifying

00:17:26.579 --> 00:17:28.960
the laxity. Okay, so a combination of the story,

00:17:29.079 --> 00:17:31.480
the general exam, and these specific tests usually

00:17:31.480 --> 00:17:33.920
gives a strong indication. What about imaging?

00:17:34.420 --> 00:17:36.500
X -rays can't see ligaments directly, can they?

00:17:36.759 --> 00:17:39.259
No, that's right. Standard X -rays mainly show

00:17:39.259 --> 00:17:41.480
bone. They're important initially to rule out

00:17:41.480 --> 00:17:43.960
any fractures associated with the injury or to

00:17:43.960 --> 00:17:46.500
see signs like significant joint swelling. The

00:17:46.500 --> 00:17:49.720
ACL itself won't show up. However, X -rays can

00:17:49.720 --> 00:17:52.400
reveal subtle signs that are highly suggestive

00:17:52.400 --> 00:17:55.390
of an ACL tear. such as what sort of clues might

00:17:55.390 --> 00:17:58.289
you see on an x -ray? A classic sign is the second

00:17:58.289 --> 00:18:00.730
fracture. It's a tiny chip of bone pulled off

00:18:00.730 --> 00:18:03.170
the outer edge of the top of the tibia near where

00:18:03.170 --> 00:18:05.259
another ligament the enterolateral ligament,

00:18:05.259 --> 00:18:08.039
attaches. The sources state this finding is almost

00:18:08.039 --> 00:18:10.599
pathognomonic, meaning it strongly indicates

00:18:10.599 --> 00:18:14.660
an ECL tear, present in 75 % to 100 % of cases

00:18:14.660 --> 00:18:16.980
where it's seen. Wow, so that little fleck of

00:18:16.980 --> 00:18:19.680
bone is a massive clue. It really is. Other x

00:18:19.680 --> 00:18:21.460
-ray findings might include a similar fracture

00:18:21.460 --> 00:18:24.460
off the fibula head, an arcuate fracture, a depression

00:18:24.460 --> 00:18:26.559
on the outer part of the femur's lower end, a

00:18:26.559 --> 00:18:28.920
deep sulcus sign, obvious joint diffusion or

00:18:28.920 --> 00:18:31.180
swelling, or particularly in children, and a

00:18:31.180 --> 00:18:33.119
vulcan fracture where the ACL has pulled a piece

00:18:33.119 --> 00:18:35.339
of the tibial spine bone off with it. So even

00:18:35.339 --> 00:18:37.589
without seeing the ligament. X -rays provide

00:18:37.589 --> 00:18:40.890
crucial, indirect evidence. But to actually visualize

00:18:40.890 --> 00:18:44.210
the ACL and check for damage to meniscus or cartilage,

00:18:44.529 --> 00:18:46.809
MRI is the key tool, isn't it? Correct. Magnetic

00:18:46.809 --> 00:18:49.509
Resonance Imaging, MRI, is considered the primary

00:18:49.509 --> 00:18:52.170
imaging modality. It's used to confirm the ACL

00:18:52.170 --> 00:18:54.650
tear diagnosis and, very importantly, to evaluate

00:18:54.650 --> 00:18:56.650
all the other structures within the knee, the

00:18:56.650 --> 00:18:58.930
menisci, the articular cartilage, the other ligaments.

00:18:59.529 --> 00:19:01.670
While a good clinical exam can often diagnose

00:19:01.670 --> 00:19:04.849
an ACL tear reliably, the MRI gives that detailed

00:19:04.849 --> 00:19:07.619
map of any associated damage, which is vital

00:19:07.619 --> 00:19:10.000
for planning the right treatment. And how accurate

00:19:10.000 --> 00:19:12.819
is MRI for spotting ACL tears? Very accurate.

00:19:12.900 --> 00:19:15.240
The source is typically, quote, sensitivity between

00:19:15.240 --> 00:19:19.180
86 % and 97 % and specificity correctly identifying

00:19:19.180 --> 00:19:22.059
when it's not torn between 95 % and 100%. What

00:19:22.059 --> 00:19:24.420
does a torn ACL actually look like on the scan?

00:19:24.670 --> 00:19:27.450
Well, a normal ACL usually appears as a continuous

00:19:27.450 --> 00:19:30.609
dark band on the MRI images, particularly the

00:19:30.609 --> 00:19:33.130
sagittal views looking from the side. When it's

00:19:33.130 --> 00:19:35.529
torn, you might see a clear break in those fibers,

00:19:35.670 --> 00:19:38.250
or the ligament might look wavy, thickened, or

00:19:38.250 --> 00:19:40.170
have increased signal within it, making it look

00:19:40.170 --> 00:19:42.589
brighter on certain sequences. Sometimes it's

00:19:42.589 --> 00:19:44.589
just not clearly visualized where it should be,

00:19:44.890 --> 00:19:47.430
or its angle looks abnormal compared to bony

00:19:47.430 --> 00:19:50.720
landmarks like Blumensatz line. On coronal views

00:19:50.720 --> 00:19:53.200
from the front, you might see discontinuity or

00:19:53.200 --> 00:19:55.460
just fluid signal in the space where the ACL

00:19:55.460 --> 00:19:57.680
should be sometimes called the empty notch sign.

00:19:57.950 --> 00:20:00.849
So looking for disruption, abnormal signal, or

00:20:00.849 --> 00:20:03.069
just absence of the normal structure, are there

00:20:03.069 --> 00:20:05.490
other signs on MRI like that bone bruising you

00:20:05.490 --> 00:20:07.690
mentioned? Yes, bone bruising is a very common

00:20:07.690 --> 00:20:10.329
secondary finding in acute tears seen in more

00:20:10.329 --> 00:20:13.109
than half of cases. These show up as areas of

00:20:13.109 --> 00:20:15.490
edema or fluid signal within the bone marrow,

00:20:15.529 --> 00:20:18.170
typically in characteristic spots. The middle

00:20:18.170 --> 00:20:20.309
part of the lateral femoral condyle and the back

00:20:20.309 --> 00:20:23.190
part of the lateral tibial plateau. It's thought

00:20:23.190 --> 00:20:25.410
these bruises reflect the impact forces during

00:20:25.410 --> 00:20:28.180
the injury. And they might have longer term implications?

00:20:28.640 --> 00:20:31.000
Possibly. The source has mentioned these bone

00:20:31.000 --> 00:20:33.779
bruises can sometimes persist for years and might

00:20:33.779 --> 00:20:36.299
contribute to the later development of osteoarthritis.

00:20:36.960 --> 00:20:39.259
Other secondary MRI signs could include visible

00:20:39.259 --> 00:20:42.079
damage to the MCL or objective measurement of

00:20:42.079 --> 00:20:44.200
more than seven millimeters of anterior tibial

00:20:44.200 --> 00:20:47.279
shift on the sagittal view. That bone bruising

00:20:47.279 --> 00:20:50.279
idea potentially linking to later arthritis is

00:20:50.279 --> 00:20:53.640
sobering. What about CT scans? Are they useful

00:20:53.640 --> 00:20:56.769
for diagnosing ACL tears? Generally, no, not

00:20:56.769 --> 00:20:59.329
for the initial diagnosis of the ACL tear itself.

00:20:59.950 --> 00:21:02.289
CT is much better at looking at bone detail than

00:21:02.289 --> 00:21:05.009
soft tissues like ligaments. However, the sources

00:21:05.009 --> 00:21:07.250
highlight that CT scans become very valuable

00:21:07.250 --> 00:21:10.009
in the revision setting. When a previous reconstruction

00:21:10.009 --> 00:21:12.470
has failed. Exactly. If someone needs surgery

00:21:12.470 --> 00:21:15.309
because a previous ACL graft hasn't worked, a

00:21:15.309 --> 00:21:17.690
CT scan is the best test to accurately assess

00:21:17.690 --> 00:21:19.750
the condition of the bone tunnels created during

00:21:19.750 --> 00:21:22.259
the first surgery. It can show if the tunnels

00:21:22.259 --> 00:21:24.180
have widened significantly or if there's bone

00:21:24.180 --> 00:21:26.220
loss, which is critical information for planning

00:21:26.220 --> 00:21:28.940
the revision operation. Okay, so MRI for the

00:21:28.940 --> 00:21:31.279
initial soft tissue picture, x -rays for bony

00:21:31.279 --> 00:21:35.039
clues, and CT, mainly for revision surgery planning.

00:21:36.160 --> 00:21:39.599
Is looking inside with a camera arthroscopy ever

00:21:39.599 --> 00:21:42.700
used just for diagnosis? Yes, knee arthroscopy

00:21:42.700 --> 00:21:45.140
keyhole surgery allows the surgeon to directly

00:21:45.140 --> 00:21:48.710
look at the ACL and confirm if it's torn. and

00:21:48.710 --> 00:21:50.910
whether it's a partial or complete tear. This

00:21:50.910 --> 00:21:52.789
is often done as the first step of the actual

00:21:52.789 --> 00:21:55.069
reconstruction surgery anyway. And injecting

00:21:55.069 --> 00:21:57.619
dye, orthography. Arthrography is mentioned as

00:21:57.619 --> 00:22:00.059
being highly accurate, technically the gold standard

00:22:00.059 --> 00:22:02.680
for sensitivity and specificity in some older

00:22:02.680 --> 00:22:05.299
literature. But because it's invasive, involving

00:22:05.299 --> 00:22:07.779
an injection into the joint, it's very rarely

00:22:07.779 --> 00:22:10.700
used nowadays as a primary diagnostic tool when

00:22:10.700 --> 00:22:12.900
MRI is so effective and non -invasive. Right,

00:22:12.960 --> 00:22:15.160
so usually it's the clinical exam plus the MRI

00:22:15.160 --> 00:22:17.019
that gives the definitive answer and maps out

00:22:17.019 --> 00:22:18.819
the damage. Okay, let's move into section three,

00:22:18.960 --> 00:22:21.220
the big decision point managing the injury, top

00:22:21.220 --> 00:22:23.619
rate or not top rate. What guides this decision

00:22:23.619 --> 00:22:25.960
according to the sources? The sources really

00:22:25.960 --> 00:22:28.819
stress that it has to be an individualized approach.

00:22:29.160 --> 00:22:31.160
There's no single right answer that fits everyone.

00:22:31.920 --> 00:22:33.680
The best course of action depends heavily on

00:22:33.680 --> 00:22:36.079
the specific patient, their age, how active they

00:22:36.079 --> 00:22:38.039
are, what demands they place on their knee in

00:22:38.039 --> 00:22:40.140
daily life or sports, whether there are other

00:22:40.140 --> 00:22:42.980
injuries in the knee like a meniscus tear. All

00:22:42.980 --> 00:22:45.759
these factors come into play. So surgery isn't

00:22:45.759 --> 00:22:49.000
automatically required for every ACL tear. When

00:22:49.000 --> 00:22:51.680
might a non -operative approach to be suitable?

00:22:51.900 --> 00:22:55.359
Non -operative management, which focuses on physiotherapy

00:22:55.359 --> 00:22:58.319
and potentially changing activities, is suggested

00:22:58.319 --> 00:23:01.220
as an option for certain groups. This might include

00:23:01.220 --> 00:23:03.579
older patients with low physical demands who

00:23:03.579 --> 00:23:05.920
aren't involved in pivoting sports, or perhaps

00:23:05.920 --> 00:23:07.960
recreational athletes who are happy to stick

00:23:07.960 --> 00:23:09.960
to straight -line activities like cycling or

00:23:09.960 --> 00:23:12.779
swimming. It might also be considered for some

00:23:12.779 --> 00:23:15.420
partial ACL tears, especially in adolescents

00:23:15.420 --> 00:23:17.819
where these are more common, if the knee feels

00:23:17.819 --> 00:23:20.140
stable and tests like Lachman's are near normal.

00:23:20.440 --> 00:23:23.259
And in young children with isolated tears, if

00:23:23.259 --> 00:23:25.619
they're low demand and can reliably avoid risky

00:23:25.619 --> 00:23:28.359
activities, a trial of non -operative treatment

00:23:28.359 --> 00:23:30.220
might be used to delay surgery until they're

00:23:30.220 --> 00:23:32.660
closer to skeletal maturity to protect their

00:23:32.660 --> 00:23:34.599
growth plates. What does that non -operative

00:23:34.599 --> 00:23:36.779
treatment typically involve? It usually starts

00:23:36.779 --> 00:23:39.339
with managing the acute symptoms, the RICE -E

00:23:39.339 --> 00:23:42.519
protocol. Rest, ice, compression, elevation,

00:23:42.720 --> 00:23:45.480
settle, pain, and swelling. Then the core is

00:23:45.480 --> 00:23:48.349
a dedicated physiotherapy program. often lasting

00:23:48.349 --> 00:23:51.170
three months or more. This focuses on regaining

00:23:51.170 --> 00:23:53.569
full knee range of motion, strengthening all

00:23:53.569 --> 00:23:56.029
the muscles around the knee and hip, crots, hamstrings,

00:23:56.210 --> 00:23:58.410
glutes, core muscles, and working on balance

00:23:58.410 --> 00:24:00.730
and neuromuscular control. Regular follow -up

00:24:00.730 --> 00:24:02.789
with a clinician is important to monitor progress

00:24:02.789 --> 00:24:05.670
and stability. Interestingly, the sources mention

00:24:05.670 --> 00:24:07.710
that functional knee braces don't seem to offer

00:24:07.710 --> 00:24:10.150
any significant added stability for people managing

00:24:10.150 --> 00:24:13.009
non -operatively. Right, the brace might feel

00:24:13.009 --> 00:24:15.630
supportive but doesn't stop the underlying instability.

00:24:15.960 --> 00:24:18.319
You mentioned trying to delay surgery in children.

00:24:19.099 --> 00:24:21.319
What are the potential downsides or risks of

00:24:21.319 --> 00:24:23.339
not having surgery, particularly for younger,

00:24:23.440 --> 00:24:25.359
active people who want to get back to sport?

00:24:25.720 --> 00:24:28.039
This is where the significant drawbacks of non

00:24:28.039 --> 00:24:30.220
-operative management become clear, especially

00:24:30.220 --> 00:24:32.759
if it's applied to the wrong patient group, like

00:24:32.759 --> 00:24:35.880
active young people. The sources point to research,

00:24:36.140 --> 00:24:38.779
like a study by Acroff, which followed children

00:24:38.779 --> 00:24:42.019
with ACL tears treated without surgery. The outcomes

00:24:42.019 --> 00:24:44.480
were concerning. They found high rates of ongoing

00:24:44.480 --> 00:24:47.599
severe instability, poor knee function, and,

00:24:47.599 --> 00:24:50.079
crucially, a very high incidence of secondary

00:24:50.079 --> 00:24:52.839
damage occurring over time. What sort of secondary

00:24:52.839 --> 00:24:55.220
damage did that study find? In that particular

00:24:55.220 --> 00:24:58.299
study, out of 23 children treated non -operatively,

00:24:58.599 --> 00:25:02.819
15 developed new meniscus tears, 3 suffered osteochondral

00:25:02.819 --> 00:25:05.640
fractures involving cartilage and bone, and 10

00:25:05.640 --> 00:25:08.960
showed early signs of osteoarthritis. This really

00:25:08.960 --> 00:25:10.960
supports the understanding that those repeated

00:25:10.960 --> 00:25:13.980
giving way episodes, the buckling due to instability,

00:25:14.519 --> 00:25:16.319
place cumulative stress on the other structures

00:25:16.319 --> 00:25:18.740
in the knee, leading to progressive damage. So

00:25:18.740 --> 00:25:21.160
those instability episodes aren't just inconvenient,

00:25:21.400 --> 00:25:23.559
they're actively harming the joint over time.

00:25:23.759 --> 00:25:27.140
Exactly. The sources stress this risk of further

00:25:27.140 --> 00:25:29.420
meniscus and cartilage injury is particularly

00:25:29.420 --> 00:25:32.000
high if the person participates in what are called

00:25:32.000 --> 00:25:35.160
Level 1 or 2 activities, basically anything involving

00:25:35.160 --> 00:25:37.519
jumping, cutting, pivoting, side -to -side movements,

00:25:37.940 --> 00:25:40.740
or heavy physical labor. So while delaying surgery

00:25:40.740 --> 00:25:42.900
in very young children to protect growth is a

00:25:42.900 --> 00:25:45.119
consideration, the sources imply that if the

00:25:45.119 --> 00:25:47.380
child simply cannot avoid these activities or

00:25:47.380 --> 00:25:49.960
the knee remains functionally unstable, the risk

00:25:49.960 --> 00:25:52.380
of causing irreversible secondary joint damage

00:25:52.380 --> 00:25:54.680
might actually outweigh the risks associated

00:25:54.680 --> 00:25:57.420
with modern growth plate sparing surgical techniques.

00:25:57.900 --> 00:25:59.700
That really highlights the challenging balance

00:25:59.700 --> 00:26:02.140
in treating children and adolescents. So given

00:26:02.140 --> 00:26:04.579
those risks associated with ongoing instability,

00:26:05.559 --> 00:26:08.779
when is operative management typically ACL reconstruction?

00:26:08.880 --> 00:26:12.400
the recommended path. ACL reconstruction, replacing

00:26:12.400 --> 00:26:14.839
the torn ligament with a graft, is generally

00:26:14.839 --> 00:26:17.619
indicated for complete ACL tears, particularly

00:26:17.619 --> 00:26:20.839
in younger, more active individuals. The evidence

00:26:20.839 --> 00:26:23.099
suggests reconstruction significantly lowers

00:26:23.099 --> 00:26:25.220
the risk of developing those secondary meniscus

00:26:25.220 --> 00:26:28.059
tears and cartilage damage down the line. For

00:26:28.059 --> 00:26:30.000
an active child or adolescent with a complete

00:26:30.000 --> 00:26:32.920
tear, realistically limiting their activity sufficiently

00:26:32.920 --> 00:26:35.619
to avoid risk is often very difficult, making

00:26:35.619 --> 00:26:38.269
surgery common recommendation. It's also recommended

00:26:38.269 --> 00:26:40.930
for older patients even over 40 if they remain

00:26:40.930 --> 00:26:43.609
highly active or have jobs with significant physical

00:26:43.609 --> 00:26:46.470
demands. Age itself isn't necessarily a barrier

00:26:46.470 --> 00:26:48.349
if the functional need is there. So it's more

00:26:48.349 --> 00:26:50.529
about the needs required function than just the

00:26:50.529 --> 00:26:53.950
patient's age. Precisely. Other indications include

00:26:53.950 --> 00:26:56.529
partial tears that still cause significant clinical

00:26:56.529 --> 00:26:59.650
instability and functional problems or cases

00:26:59.650 --> 00:27:01.609
where non -operative treatment has been tried

00:27:01.609 --> 00:27:05.470
but failed with instability persisting. If there's

00:27:05.470 --> 00:27:08.009
an associated meniscus tear that needs surgical

00:27:08.009 --> 00:27:10.710
repair, particularly if it's blocking knee movement,

00:27:11.190 --> 00:27:13.529
the ACL is often reconstructed at the same time.

00:27:14.329 --> 00:27:16.130
A really critical point mentioned repeatedly

00:27:16.130 --> 00:27:18.890
is that unless a meniscus tear is blocking motion,

00:27:19.369 --> 00:27:21.430
the patient must regain full range of motion

00:27:21.430 --> 00:27:24.970
before surgery. Operating on a stiff knee dramatically

00:27:24.970 --> 00:27:27.410
increases the risk of problematic post -operative

00:27:27.410 --> 00:27:30.869
stiffness or arthrofibrosis. And naturally, if

00:27:30.869 --> 00:27:33.529
a previous ACL reconstruction has failed, then

00:27:33.529 --> 00:27:36.569
revision surgery is indicated. Okay, so reconstruction

00:27:36.569 --> 00:27:38.789
is generally for active people needing a stable

00:27:38.789 --> 00:27:41.269
knee for dynamic activities, aiming to restore

00:27:41.269 --> 00:27:43.930
function and prevent further joint damage. The

00:27:43.930 --> 00:27:45.430
source has also mentioned something important

00:27:45.430 --> 00:27:47.430
about return to sport not just being about the

00:27:47.430 --> 00:27:51.119
physical repair. Yes. That's a key insight. Success

00:27:51.119 --> 00:27:53.519
after surgery isn't judged solely on the stability

00:27:53.519 --> 00:27:56.319
of the knee. The sources highlight that successful

00:27:56.319 --> 00:27:59.180
return to play is influenced by a whole mix of

00:27:59.180 --> 00:28:02.220
factors. Physical recovery benchmarks, performance

00:28:02.220 --> 00:28:05.160
on functional tests, demographic factors, and

00:28:05.160 --> 00:28:07.400
significantly psychological readiness, things

00:28:07.400 --> 00:28:10.079
like confidence in the knee and fear of re -injury.

00:28:10.480 --> 00:28:12.819
It underscores that recovery is a holistic process.

00:28:13.079 --> 00:28:15.430
Understood. Let's move into section four then

00:28:15.430 --> 00:28:17.650
and get into the specifics of the surgery itself.

00:28:18.210 --> 00:28:21.190
Generally speaking, how is an ACL reconstruction

00:28:21.190 --> 00:28:23.809
carried out? The standard method nowadays is

00:28:23.809 --> 00:28:25.950
arthroscopic assistant. It's keyhole surgery.

00:28:26.470 --> 00:28:28.269
The surgeon makes a few small incisions around

00:28:28.269 --> 00:28:30.690
the knee to insert a small camera, the arthroscope,

00:28:30.809 --> 00:28:33.359
and specialized thin instruments. They prepare

00:28:33.359 --> 00:28:35.539
the inside of the joint, clearing away the torn

00:28:35.539 --> 00:28:37.680
remnants of the original ACL to get good views

00:28:37.680 --> 00:28:40.019
of the bony landmarks. Although the sources do

00:28:40.019 --> 00:28:42.039
note there's no clear evidence showing a difference

00:28:42.039 --> 00:28:44.079
in outcome, whether you remove all the remnant

00:28:44.079 --> 00:28:46.480
or leave a small stump behind, which some believe

00:28:46.480 --> 00:28:48.970
might aid healing or proprioception. And you

00:28:48.970 --> 00:28:51.410
mentioned earlier the ACL has those two bundles,

00:28:51.670 --> 00:28:55.109
AM and PL. Do surgeons typically try to recreate

00:28:55.109 --> 00:28:58.049
both? Anatomically, yes, it has two main bundles.

00:28:58.309 --> 00:29:00.630
However, the most common surgical technique remains

00:29:00.630 --> 00:29:03.309
single bundle reconstruction, where one graft

00:29:03.309 --> 00:29:05.289
is positioned to replicate the function of both

00:29:05.289 --> 00:29:08.039
bundles. While double bundle reconstruction using

00:29:08.039 --> 00:29:10.680
two separate graphs might theoretically restore

00:29:10.680 --> 00:29:13.160
the knee's natural mechanics more closely and

00:29:13.160 --> 00:29:16.059
perhaps reduce laxity slightly more, the sources

00:29:16.059 --> 00:29:19.279
state that currently studies haven't shown significant

00:29:19.279 --> 00:29:21.359
differences in patient -reported outcomes between

00:29:21.359 --> 00:29:23.759
the two techniques. So the single bundle approach

00:29:23.759 --> 00:29:26.019
is standard and generally provides good results

00:29:26.019 --> 00:29:28.420
for patients. Once the graft tissue is ready,

00:29:28.619 --> 00:29:31.299
how is it actually positioned and secured inside

00:29:31.299 --> 00:29:33.680
the knee? The graft needs to be passed through

00:29:33.680 --> 00:29:36.599
bone tunnels drilled in the tibia and the femur,

00:29:36.819 --> 00:29:39.019
spanning the joint and then firmly fixed to both

00:29:39.019 --> 00:29:42.220
ends. There's a mention of preconditioning the

00:29:42.220 --> 00:29:44.720
graft, applying some gentle tension to it before

00:29:44.720 --> 00:29:47.259
final fixation, which might reduce some of the

00:29:47.259 --> 00:29:49.480
initial stretching or creep that happens after

00:29:49.480 --> 00:29:52.759
surgery. How much tension to apply during fixation

00:29:52.759 --> 00:29:55.519
seems less critical. One high -level study cited

00:29:55.519 --> 00:29:57.539
found no difference in outcomes between using

00:29:57.539 --> 00:30:00.559
20 or 40 newtons of tension. The graft is usually

00:30:00.559 --> 00:30:03.019
fixed with the knee held in about 20 to 30 degrees

00:30:03.019 --> 00:30:05.119
of flexion. And how do they actually anchor it?

00:30:05.180 --> 00:30:07.579
What are the fixation devices used? There are

00:30:07.579 --> 00:30:09.599
quite a few options, and the choice often depends

00:30:09.599 --> 00:30:13.119
on the type of graft being used. Fiji, bone plugs

00:30:13.119 --> 00:30:17.160
versus soft tissue, and surgeon preference. Collin

00:30:17.160 --> 00:30:19.700
methods include interference screws. These are

00:30:19.700 --> 00:30:21.779
screwed into the tunnel alongside the graft,

00:30:22.299 --> 00:30:24.859
wedging it tightly against the bone wall. Another

00:30:24.859 --> 00:30:27.660
major category is suspensory fixation, like cortical

00:30:27.660 --> 00:30:29.640
buttons, where the graft is essentially hung

00:30:29.640 --> 00:30:31.640
from a small button resting on the outer surface

00:30:31.640 --> 00:30:34.880
of the bone. Other devices like screw and washer

00:30:34.880 --> 00:30:38.180
posts or staples are also used. Sometimes a combination

00:30:38.180 --> 00:30:40.730
of methods is employed for extra security. Okay,

00:30:40.910 --> 00:30:43.329
so screws, buttons, various ways to lock the

00:30:43.329 --> 00:30:45.690
new ligament in place. The sources seem to really

00:30:45.690 --> 00:30:47.549
emphasize that exactly where those bone tunnels

00:30:47.549 --> 00:30:49.809
are drilled is incredibly important for success.

00:30:49.990 --> 00:30:53.069
Why is tunnel placement so critical? It's paramount.

00:30:53.349 --> 00:30:55.750
Tunnel placement dictates the position and angle

00:30:55.750 --> 00:30:58.470
of the new graft within the joint. The goal is

00:30:58.470 --> 00:31:00.670
to place the tunnels, and therefore the graft,

00:31:01.170 --> 00:31:03.470
as close as possible to the location of the original

00:31:03.470 --> 00:31:06.740
ACL. This is essential not just for restoring

00:31:06.740 --> 00:31:09.660
the street forward anterior stability, but crucially

00:31:09.660 --> 00:31:13.299
for restoring rotational stability as well. Getting

00:31:13.299 --> 00:31:15.559
the tunnels drilled in a non -anatomical position

00:31:15.559 --> 00:31:17.539
is cited as the single most common technical

00:31:17.539 --> 00:31:20.400
error leading to graft failure. So precision

00:31:20.400 --> 00:31:22.619
aiming is absolutely key. What are the guiding

00:31:22.619 --> 00:31:24.880
principles for getting those tunnels in the right

00:31:24.880 --> 00:31:27.240
spot? For the femoral tunnel in the thigh bone,

00:31:27.700 --> 00:31:29.440
the surgeon needs to place it correctly both

00:31:29.440 --> 00:31:33.839
side to side, coronally, and front to back. Placing

00:31:33.839 --> 00:31:36.720
it too vertically fails to control rotation effectively.

00:31:37.299 --> 00:31:38.859
Placing it too far forward can make the knee

00:31:38.859 --> 00:31:41.319
feel tight and bending, but loose when straight.

00:31:42.019 --> 00:31:44.400
Placing it too far back risks breaking through

00:31:44.400 --> 00:31:46.839
the back wall of the bone. Different drilling

00:31:46.839 --> 00:31:49.779
techniques exist transcivial versus using separate

00:31:49.779 --> 00:31:52.779
portals, but the sources suggest no major outcome

00:31:52.779 --> 00:31:55.140
differences as long as the final placement is

00:31:55.140 --> 00:31:57.859
anatomical. Drilling this tunnel with a knee

00:31:57.859 --> 00:32:00.700
significantly bent helps prevent that posterior

00:32:00.700 --> 00:32:03.680
wall blowout. For the tibial tunnel in the shin

00:32:03.680 --> 00:32:05.640
bone, its position relative to the remaining

00:32:05.640 --> 00:32:09.039
PCL and other landmarks is crucial. If it's too

00:32:09.039 --> 00:32:11.220
far forward, the graft can impinge on the roof

00:32:11.220 --> 00:32:13.279
of the joint when the knee straightens. If it's

00:32:13.279 --> 00:32:16.099
too far back, it might impinge on the PCL. The

00:32:16.099 --> 00:32:18.579
angle it's drilled at is also important. It sounds

00:32:18.579 --> 00:32:20.940
like navigating those tunnels requires extreme

00:32:20.940 --> 00:32:23.680
precision. You also mentioned earlier that ACL

00:32:23.680 --> 00:32:25.920
repair, fixing the original ligament, is seeing

00:32:25.920 --> 00:32:28.720
some renewed interest. How does that differ from

00:32:28.720 --> 00:32:30.799
reconstruction and when might it be considered?

00:32:31.259 --> 00:32:34.200
Yes, repair involves attempting to reattach the

00:32:34.200 --> 00:32:36.880
patient's own torn ACL rather than replacing

00:32:36.880 --> 00:32:40.569
it entirely with a graft. Historically, ACL repairs

00:32:40.569 --> 00:32:43.750
had very high failure rates, which led to reconstruction

00:32:43.750 --> 00:32:47.069
becoming the standard. However, there's definitely

00:32:47.069 --> 00:32:49.569
been a resurgence of interest recently, particularly

00:32:49.569 --> 00:32:52.210
for very specific types of tears and potentially

00:32:52.210 --> 00:32:54.869
in children. What kind of specific tears might

00:32:54.869 --> 00:32:57.009
be suitable for repair, according to the sources?

00:32:57.210 --> 00:32:59.890
The main indication mentioned is for ACL evulsion

00:32:59.890 --> 00:33:02.710
injuries. This is where the ligament itself is

00:33:02.710 --> 00:33:05.140
largely intact. but has been pulled off its bony

00:33:05.140 --> 00:33:07.420
attachment, either on the femur or the tibia,

00:33:07.519 --> 00:33:09.640
sometimes taking a piece of bone with it. It's

00:33:09.640 --> 00:33:12.160
not generally considered for tears within the

00:33:12.160 --> 00:33:14.920
main substance of the ligament itself. In adolescent

00:33:14.920 --> 00:33:17.099
sneering skeletal maturity, certain repair techniques

00:33:17.099 --> 00:33:20.000
using suture anchors or suspensory fixation might

00:33:20.000 --> 00:33:22.259
offer a way to restore stability with potentially

00:33:22.259 --> 00:33:24.940
less risk to the growth plate compared to drilling

00:33:24.940 --> 00:33:27.519
large tunnels for a reconstruction graft. And

00:33:27.519 --> 00:33:29.599
are the outcomes improving with these newer repair

00:33:29.599 --> 00:33:32.269
methods? It's an evolving field. The sources

00:33:32.269 --> 00:33:34.890
acknowledge the poor historical results, but

00:33:34.890 --> 00:33:37.230
note that newer techniques, sometimes combined

00:33:37.230 --> 00:33:40.049
with biological augmentation scaffolds like the

00:33:40.049 --> 00:33:42.910
Bayer implant trial, are being investigated and

00:33:42.910 --> 00:33:45.190
showing some promising early results in specific

00:33:45.190 --> 00:33:48.190
patient groups, with comparable outcomes to reconstruction

00:33:48.190 --> 00:33:50.470
reported at the two -year mark in some studies.

00:33:50.730 --> 00:33:53.809
But it's not yet mainstream for most ACL tears.

00:33:54.390 --> 00:33:56.930
Interesting. One to watch, perhaps. What about

00:33:56.930 --> 00:33:59.670
the situation where a previous ACL reconstruction

00:33:59.670 --> 00:34:02.269
has failed that requires a revision surgery you

00:34:02.269 --> 00:34:04.769
mentioned? Yes, ACL revision reconstruction is

00:34:04.769 --> 00:34:07.349
necessary when the initial graft fails and the

00:34:07.349 --> 00:34:09.489
patient is experiencing unacceptable instability

00:34:09.489 --> 00:34:12.110
during their desired activities. It's typically

00:34:12.110 --> 00:34:14.050
a more complex operation than the first time

00:34:14.050 --> 00:34:16.510
surgery. What makes revision surgery more challenging?

00:34:16.889 --> 00:34:19.050
Several things. Firstly, the surgeon needs to

00:34:19.050 --> 00:34:21.690
figure out why the first one failed. Was it a

00:34:21.690 --> 00:34:24.130
technical error like tunnel malposition? Was

00:34:24.130 --> 00:34:26.769
a graft choice inappropriate? Did the fixation

00:34:26.769 --> 00:34:30.010
fail? Was there an undiagnosed associated injury

00:34:30.010 --> 00:34:32.329
putting extra stress on the graft? or did the

00:34:32.329 --> 00:34:35.030
patient re -injure it? Secondly, the bone tunnels

00:34:35.030 --> 00:34:37.230
from the first surgery are often enlarged or

00:34:37.230 --> 00:34:40.150
may be positioned non -anatomically, which complicates

00:34:40.150 --> 00:34:43.530
drilling new tunnels correctly. Thirdly, graft

00:34:43.530 --> 00:34:46.190
choice becomes more critical. The sources generally

00:34:46.190 --> 00:34:48.710
recommend using high -strength grafts for revisions.

00:34:48.909 --> 00:34:51.170
Often autografts like quadriceps tendon or hamstring

00:34:51.170 --> 00:34:54.050
is available, or sometimes allograft, donor tissue.

00:34:54.690 --> 00:34:57.030
Re -harvesting a BPTV graft from the same knees

00:34:57.030 --> 00:34:59.639
usually advised against because the bone quality

00:34:59.639 --> 00:35:02.199
might be compromised, surgeons often use enhanced

00:35:02.199 --> 00:35:04.719
fixation methods, perhaps dual fixation points.

00:35:05.300 --> 00:35:07.900
If the old tunnels are very large, say over 50

00:35:07.900 --> 00:35:10.260
millimeter, or interfere with replacing new tunnels

00:35:10.260 --> 00:35:12.460
anatomically, the revision might need to be staged

00:35:12.460 --> 00:35:14.260
first surgery to bone graft the old tunnels,

00:35:14.679 --> 00:35:16.239
then a second surgery months later to do the

00:35:16.239 --> 00:35:18.059
reconstruction. There's also some debate about

00:35:18.059 --> 00:35:21.059
adding procedures, like a lateral extra -articular

00:35:21.059 --> 00:35:24.679
tenodesis, LET. In revision cases, particularly

00:35:24.679 --> 00:35:27.159
in young, high -risk patients, to provide extra

00:35:27.159 --> 00:35:29.480
rotational control, though its routine use is

00:35:29.480 --> 00:35:32.019
still controversial. Rehab after revision is

00:35:32.019 --> 00:35:34.760
often more cautious, too. So revision is definitely

00:35:34.760 --> 00:35:37.639
a step up in complexity, requiring careful investigation

00:35:37.639 --> 00:35:40.940
and planning. Let's revisit graft selection for

00:35:40.940 --> 00:35:43.639
primary reconstructions. You outlined a few options,

00:35:43.800 --> 00:35:47.840
BPTB, hamstring, quad tendon, allograft. Can

00:35:47.840 --> 00:35:50.039
you summarize the key pros and cons the sources

00:35:50.039 --> 00:35:52.940
highlight for each? Certainly. This is a really

00:35:52.940 --> 00:35:54.679
important discussion because the graft choice

00:35:54.679 --> 00:35:57.579
impacts things like recovery, potential complications

00:35:57.579 --> 00:36:00.059
like pain, and maybe even long -term outcomes

00:36:00.059 --> 00:36:02.960
or re -repture risk. Autographs using the patient's

00:36:02.960 --> 00:36:05.360
own tissue have the biological advantage of faster

00:36:05.360 --> 00:36:08.349
incorporation, no immune reaction, and no disease

00:36:08.349 --> 00:36:10.829
transmission risk. The downside is you have to

00:36:10.829 --> 00:36:13.090
harvest it from somewhere, creating morbidity

00:36:13.090 --> 00:36:15.250
at the donor site. Let's start with the bone

00:36:15.250 --> 00:36:18.070
patellar tendon bone, BPTV, often called the

00:36:18.070 --> 00:36:20.050
gold standard. It's frequently referred to that

00:36:20.050 --> 00:36:22.409
way, yes, partly due to its long track record

00:36:22.409 --> 00:36:24.969
of successful use, especially in high level athletes.

00:36:25.750 --> 00:36:28.030
The main pro is that it provides bone plugs at

00:36:28.030 --> 00:36:30.489
each end, allowing for bone to bone healing within

00:36:30.489 --> 00:36:32.969
the tunnels, which is thought to be faster and

00:36:32.969 --> 00:36:35.630
potentially more rigid early on. It's also a

00:36:35.630 --> 00:36:38.809
very strong graft. The major con cited consistently

00:36:38.809 --> 00:36:41.769
is a higher incidence of anterior knee pain at

00:36:41.769 --> 00:36:43.929
the front of the knee, particularly when kneeling.

00:36:44.489 --> 00:36:47.510
This is reported in 10 -30 % of patients. Rare

00:36:47.510 --> 00:36:50.190
complications include patella fracture or patellar

00:36:50.190 --> 00:36:52.730
tendon rupture. There's also a note about potentially

00:36:52.730 --> 00:36:55.190
higher re -rupture risk if used in very young

00:36:55.190 --> 00:36:58.030
patients under 20, or if the graft harvested

00:36:58.030 --> 00:37:00.349
is less than eight millimeters wide. So strong

00:37:00.349 --> 00:37:02.989
and reliable fixation, but potential for harvest

00:37:02.989 --> 00:37:05.230
site pain. What about the hamstring autograph?

00:37:05.409 --> 00:37:07.789
That seems incredibly common now. It is, yes.

00:37:07.829 --> 00:37:10.570
Typically two tendons, semitendinosus and gracilis,

00:37:11.150 --> 00:37:13.429
are harvested and folded over to create a four

00:37:13.429 --> 00:37:16.929
-strand The main advantages are usually a smaller

00:37:16.929 --> 00:37:19.590
incision, less pain immediately after surgery,

00:37:20.010 --> 00:37:22.449
and significantly less anterior knee pain compared

00:37:22.449 --> 00:37:25.590
to BPTB. It's also mechanically very strong,

00:37:25.989 --> 00:37:28.969
often stronger than BPTB in lab testing. Potential

00:37:28.969 --> 00:37:30.989
downsides include a theoretical concern about

00:37:30.989 --> 00:37:32.969
residual hamstring weakness, especially peak

00:37:32.969 --> 00:37:35.090
flexion strength, although the functional impact

00:37:35.090 --> 00:37:37.579
is debated. Some sources raise a question about

00:37:37.579 --> 00:37:39.280
whether this weakness, particularly in females,

00:37:39.400 --> 00:37:41.599
could slightly increase rupture risk, but again,

00:37:41.679 --> 00:37:43.880
that's not definitively proven. Is that hamstring

00:37:43.880 --> 00:37:46.880
weakness usually noticeable long term? It can

00:37:46.880 --> 00:37:49.119
be measurable, but whether it affects function

00:37:49.119 --> 00:37:52.420
significantly varies. Other potential complications

00:37:52.420 --> 00:37:54.739
include nerve irritation near the harvacite,

00:37:54.820 --> 00:37:57.840
causing numbness, peristhesia, though certain

00:37:57.840 --> 00:38:01.159
incision techniques might reduce this risk. Also,

00:38:01.380 --> 00:38:03.219
because hamstring grafts are typically fixed

00:38:03.219 --> 00:38:05.900
with suspensory devices like buttons, there's

00:38:05.900 --> 00:38:08.500
the potential for a windshield wiper or bungee

00:38:08.500 --> 00:38:10.860
cord effect, where the graft moves slightly within

00:38:10.860 --> 00:38:12.900
the tunnels, which might lead to some tunnel

00:38:12.900 --> 00:38:15.400
widening over time, though the clinical relevance

00:38:15.400 --> 00:38:17.559
of this is also debated. That windshield wiper

00:38:17.559 --> 00:38:20.239
image is quite descriptive. How about the quadriceps

00:38:20.239 --> 00:38:22.519
tendon autograft? Is that becoming more popular?

00:38:22.800 --> 00:38:25.340
It seems to be gaining traction, yes. It can

00:38:25.340 --> 00:38:28.059
be harvested just as soft tissue or with a bone

00:38:28.059 --> 00:38:30.710
block from the top of the patella. Key advantages

00:38:30.710 --> 00:38:32.889
include the harvest incision being away from

00:38:32.889 --> 00:38:34.909
the area you kneel on, which is beneficial for

00:38:34.909 --> 00:38:37.369
some patients. If harvested without the bone

00:38:37.369 --> 00:38:39.630
block, it avoids crossing the growth plate in

00:38:39.630 --> 00:38:42.070
the tibia, making it a potentially good option

00:38:42.070 --> 00:38:44.409
for skeletally immature patients compared to

00:38:44.409 --> 00:38:47.710
BPTB. Its strength is good, comparable to the

00:38:47.710 --> 00:38:50.429
native ACL, and patient outcomes seem similar

00:38:50.429 --> 00:38:52.909
to other autografts. It's also often available

00:38:52.909 --> 00:38:55.170
as a virgin graft option for revision surgeries.

00:38:55.980 --> 00:38:58.099
Disadvantages are similar to hamstring grafts

00:38:58.099 --> 00:39:00.860
if soft tissue fixation is used regarding potential

00:39:00.860 --> 00:39:03.420
tunnel effects. So, perhaps a useful alternative

00:39:03.420 --> 00:39:06.079
in certain situations. Lastly, allograft using

00:39:06.079 --> 00:39:08.400
tissue from a donor. Pros and cons. The main

00:39:08.400 --> 00:39:10.539
advantage of allograft is avoiding harvacite

00:39:10.539 --> 00:39:13.519
morbidity altogether. This is particularly useful

00:39:13.519 --> 00:39:15.920
in revision surgeries where good autograft options

00:39:15.920 --> 00:39:18.679
might be limited or in complex cases involving

00:39:18.679 --> 00:39:21.369
multiple ligament injuries. However, there are

00:39:21.369 --> 00:39:24.289
significant downsides. Allografts are more expensive.

00:39:24.489 --> 00:39:26.510
Biologically, they take longer to incorporate

00:39:26.510 --> 00:39:29.670
into the patient's bone tunnels compared to autografts.

00:39:29.789 --> 00:39:32.710
There's a very small but real risk of disease

00:39:32.710 --> 00:39:34.909
transmission, although rigorous screening makes

00:39:34.909 --> 00:39:38.289
this extremely rare. HIV risk is cited as less

00:39:38.289 --> 00:39:41.389
than 1 in 1 .6 million. But the biggest concern

00:39:41.389 --> 00:39:43.789
highlighted in the sources, especially for young

00:39:43.789 --> 00:39:46.650
active patients, is a markedly increased risk

00:39:46.650 --> 00:39:49.489
of graft failure or re -rupture. How much higher

00:39:49.489 --> 00:39:51.570
is that rupture risk with allograft in young

00:39:51.570 --> 00:39:54.170
people? The data cited is striking. For athletes

00:39:54.170 --> 00:39:56.909
aged between 10 and 19 undergoing primary ACL

00:39:56.909 --> 00:39:59.610
reconstruction, the odds of graft rupture were

00:39:59.610 --> 00:40:02.250
reported to be over four times higher with allograft

00:40:02.250 --> 00:40:04.829
compared to using their own tissue, autograft.

00:40:05.409 --> 00:40:07.489
That's a massive difference and a major factor

00:40:07.489 --> 00:40:09.369
influencing graft choice in that population.

00:40:09.530 --> 00:40:12.590
A very powerful statistic indeed. Does the way

00:40:12.590 --> 00:40:15.230
the allograft tissue is processed make a difference

00:40:15.230 --> 00:40:18.269
to its quality or risk? Yes. Processing methods

00:40:18.269 --> 00:40:21.250
matter. Fresh frozen allografts generally show

00:40:21.250 --> 00:40:23.289
lower rupture rates compared to those treated

00:40:23.289 --> 00:40:26.230
with chemicals or radiation. Irradiation, used

00:40:26.230 --> 00:40:28.789
for sterilization, unfortunately weakens the

00:40:28.789 --> 00:40:31.909
graft's mechanical properties. Higher doses significantly

00:40:31.909 --> 00:40:34.610
reduce strength, and even lower doses decrease

00:40:34.610 --> 00:40:38.150
stiffness. Other methods like defreezing or certain

00:40:38.150 --> 00:40:41.030
chemical treatments might damage cells but not

00:40:41.030 --> 00:40:43.809
significantly affect immediate strength. So fresh

00:40:43.809 --> 00:40:46.130
frozen seems the preferred allograft type when

00:40:46.130 --> 00:40:49.809
it's used. Let's loop back to the pediatric considerations.

00:40:50.210 --> 00:40:52.469
We touched on the risk to open growth plates,

00:40:52.829 --> 00:40:55.949
freezes. How do surgeons navigate this when operating

00:40:55.949 --> 00:40:57.909
on children who are still growing? It's a major

00:40:57.909 --> 00:41:00.469
challenge, absolutely. Injuring those active

00:41:00.469 --> 00:41:02.809
growth plates during surgery, especially by drilling

00:41:02.809 --> 00:41:05.519
large tunnels across them or using fixation methods

00:41:05.519 --> 00:41:08.119
that compress them can potentially lead to problems

00:41:08.119 --> 00:41:10.360
like premature growth arrest, angular deformities

00:41:10.360 --> 00:41:12.320
of the leg, or differences in leg length later

00:41:12.320 --> 00:41:15.340
on. How do they judge when a child is safe for

00:41:15.340 --> 00:41:18.480
more adult -type surgery techniques? Skeletal

00:41:18.480 --> 00:41:21.619
maturity is key. The sources suggest onset of

00:41:21.619 --> 00:41:23.780
menstruation is often a good guide for girls

00:41:23.780 --> 00:41:26.980
nearing maturity. Generally, males age 16 or

00:41:26.980 --> 00:41:29.699
older and females 14 or older are often considered

00:41:29.699 --> 00:41:31.739
to have mature enough growth plates to tolerate

00:41:31.739 --> 00:41:34.280
adult -type reconstruction techniques. For younger

00:41:34.280 --> 00:41:37.059
children with significantly open fices, surgeons

00:41:37.059 --> 00:41:39.239
employ specific techniques designed to either

00:41:39.239 --> 00:41:41.559
completely avoid drilling across the fizzes,

00:41:41.800 --> 00:41:44.199
fizzle sparing, or to minimize the risk of damaging

00:41:44.199 --> 00:41:49.380
it, fizzle respecting. There are various approaches

00:41:49.380 --> 00:41:52.480
described. Some techniques keep the tunnels entirely

00:41:52.480 --> 00:41:54.809
within the ends of the bones, the epithesis,

00:41:55.269 --> 00:41:57.869
avoiding the fissus altogether. Others might

00:41:57.869 --> 00:42:00.449
cross one fissus but try to do so minimally,

00:42:00.750 --> 00:42:03.670
often centrally and vertically, partial transfusceal.

00:42:04.150 --> 00:42:06.909
And there are full transfusceal techniques, similar

00:42:06.909 --> 00:42:09.530
to adult surgery but using smaller tunnels drilled

00:42:09.530 --> 00:42:11.989
very carefully to minimize the area of fissus

00:42:11.989 --> 00:42:14.719
affected. Interestingly, the sources suggest

00:42:14.719 --> 00:42:16.960
there aren't huge differences reported in growth

00:42:16.960 --> 00:42:19.500
disturbance rates between these different specialized

00:42:19.500 --> 00:42:22.219
pediatric techniques, implying that meticulous

00:42:22.219 --> 00:42:24.280
surgical execution might be the most critical

00:42:24.280 --> 00:42:26.579
factor. So they all carry some inherent risk,

00:42:26.659 --> 00:42:29.199
but the techniques aim to be as safe as possible.

00:42:29.639 --> 00:42:31.420
Are there techniques that involve structures

00:42:31.420 --> 00:42:34.260
outside the joint as well? Yes, for very young

00:42:34.260 --> 00:42:37.280
children. EG males under 12, females under 11.

00:42:37.739 --> 00:42:40.280
Sometimes combined intraarticular and extraarticular

00:42:40.280 --> 00:42:43.139
techniques are used. One example described uses

00:42:43.139 --> 00:42:46.440
a strip of the iliotildial band, ITB, from the

00:42:46.440 --> 00:42:48.980
outside of the thigh. It's harvested and routed

00:42:48.980 --> 00:42:51.239
in a way that provides stability inside the joint

00:42:51.239 --> 00:42:54.280
but avoids drilling across the main distal femoral

00:42:54.280 --> 00:42:57.000
fissus, offering stability while minimizing growth

00:42:57.000 --> 00:42:59.820
risk. And what about graft choice specifically

00:42:59.820 --> 00:43:02.260
in children? The sources strongly indicate that

00:43:02.260 --> 00:43:04.789
if a transfissal technique is used, crossing

00:43:04.789 --> 00:43:07.030
the growth plate using a soft tissue graft like

00:43:07.030 --> 00:43:10.050
hamstring, carry a significantly lower risk of

00:43:10.050 --> 00:43:12.329
causing growth problems compared to using a graft

00:43:12.329 --> 00:43:14.929
with bone blocks like BPTV that pass through

00:43:14.929 --> 00:43:17.489
the physis. What are the biggest surgical mistakes

00:43:17.489 --> 00:43:19.690
or factors that increase the risk of damaging

00:43:19.690 --> 00:43:22.289
a growth plate in kids? The single most important

00:43:22.289 --> 00:43:24.769
factor highlighted is the diameter of the tunnels

00:43:24.769 --> 00:43:27.550
drilled across the physis. Larger tunnels obviously

00:43:27.550 --> 00:43:29.510
damage a larger percentage of the growth plate

00:43:29.510 --> 00:43:33.599
area. An 8mm tunnel might violate less than 3%,

00:43:33.599 --> 00:43:36.980
while a 12mm tunnel could affect 7 -9 % or more.

00:43:37.880 --> 00:43:39.960
Other risk factors include drilling tunnels at

00:43:39.960 --> 00:43:42.539
very oblique angles across the physis, using

00:43:42.539 --> 00:43:44.960
fixation devices like interference screws directly

00:43:44.960 --> 00:43:47.400
across the physis, using high -speed burrs instead

00:43:47.400 --> 00:43:50.199
of drills, adding certain extra -articular procedures,

00:43:50.920 --> 00:43:53.300
dissecting too close to sensitive growth cartilage

00:43:53.300 --> 00:43:56.039
around the joint edges, or placing sutures near

00:43:56.039 --> 00:43:59.019
the tibial tubercle growth area. Despite all

00:43:59.019 --> 00:44:01.539
care, the sources do note that some minor physical

00:44:01.539 --> 00:44:04.139
disruption, visible on imaging but not causing

00:44:04.139 --> 00:44:06.579
clinical growth problems, is reported in around

00:44:06.579 --> 00:44:09.800
10 % of pediatric ACL cases. It really does underscore

00:44:09.800 --> 00:44:12.360
the immense care and precision needed when operating

00:44:12.360 --> 00:44:15.320
on a growing knee. Balancing stability with protecting

00:44:15.320 --> 00:44:17.880
future growth is clearly a huge consideration.

00:44:18.159 --> 00:44:20.159
It demands significant expertise and very careful

00:44:20.159 --> 00:44:22.539
judgment, yes. Okay, we've thoroughly covered

00:44:22.539 --> 00:44:25.519
the injury, how it's diagnosed, the decisions

00:44:25.519 --> 00:44:27.969
around surgery. the different techniques including

00:44:27.969 --> 00:44:31.570
for children, and graft choices. Let's move now

00:44:31.570 --> 00:44:34.769
to what happens after surgery. Section five,

00:44:34.929 --> 00:44:38.010
focusing on recovery, rehabilitation, and potential

00:44:38.010 --> 00:44:40.809
setbacks. What's the main goal right after the

00:44:40.809 --> 00:44:43.869
operation? The overall aim of the post -op care

00:44:43.869 --> 00:44:47.090
and the entire rehab process is to safely restore

00:44:47.090 --> 00:44:49.710
the knee's normal function, stability, and movement

00:44:49.710 --> 00:44:52.230
patterns, ultimately allowing the patient to

00:44:52.230 --> 00:44:54.690
return to their desired activities, including

00:44:54.690 --> 00:44:57.659
sports, at a high level. Immediately after surgery

00:44:57.659 --> 00:45:00.820
the focus is on managing pain and swelling. Aggressive

00:45:00.820 --> 00:45:03.800
cryotherapy using ice or specialized cold compression

00:45:03.800 --> 00:45:06.480
devices is really emphasized. Why the big push

00:45:06.480 --> 00:45:08.840
on ice? The sources note it significantly helps

00:45:08.840 --> 00:45:11.300
reduce pain and consequently the need for strong

00:45:11.300 --> 00:45:14.059
pain medication. Early weight -bearing as tolerated

00:45:14.059 --> 00:45:15.940
is also generally encouraged these days. It's

00:45:15.940 --> 00:45:17.320
been linked to less pain at the front of the

00:45:17.320 --> 00:45:19.440
knee later on. And getting that knee moving straight

00:45:19.440 --> 00:45:22.019
away is important. Absolutely critical, especially

00:45:22.019 --> 00:45:24.780
regaining full passive extension, getting the

00:45:24.780 --> 00:45:27.400
knee completely straight passively. This should

00:45:27.400 --> 00:45:29.659
be a priority from day one. It's particularly

00:45:29.659 --> 00:45:31.699
vital if there were associated injuries like

00:45:31.699 --> 00:45:34.019
an MCL sprain or patella dislocation treated

00:45:34.019 --> 00:45:36.579
at the same time. Interestingly, the sources

00:45:36.579 --> 00:45:38.440
also mentioned that research hasn't really shown

00:45:38.440 --> 00:45:41.360
any major long -term differences between following

00:45:41.360 --> 00:45:44.440
very aggressive accelerated rehab protocols versus

00:45:44.440 --> 00:45:47.530
more traditional slower progressions. So the

00:45:47.530 --> 00:45:49.789
exact speed might matter less than hitting the

00:45:49.789 --> 00:45:52.489
key milestones. What kind of exercises are typically

00:45:52.489 --> 00:45:54.889
done in the early stages of rehab? What's considered

00:45:54.889 --> 00:45:57.130
safe and what should definitely be avoided? Early

00:45:57.130 --> 00:45:59.889
rehab focuses on activating muscles and restoring

00:45:59.889 --> 00:46:02.710
motion without putting undue stress on the healing

00:46:02.710 --> 00:46:05.630
graft. Safe bets usually include things like

00:46:05.630 --> 00:46:08.989
eccentric quadriceps. Strengthening sources suggest

00:46:08.989 --> 00:46:11.170
this can start quite early, around three weeks,

00:46:11.469 --> 00:46:14.970
and helps build muscle size and strength. Isometric

00:46:14.970 --> 00:46:16.989
contractions. Just tensing the muscles without

00:46:16.989 --> 00:46:19.329
moving the joint are safe for both hamstrings

00:46:19.329 --> 00:46:22.429
and quives at any angle. Gentle active range

00:46:22.429 --> 00:46:24.510
of motion, usually within a protected range like

00:46:24.510 --> 00:46:28.070
35 to 90 degrees of flexion initially, is encouraged.

00:46:28.690 --> 00:46:30.489
Core strengthening and exercises for the hip

00:46:30.489 --> 00:46:33.130
muscles, particularly the glutes, are also fundamental

00:46:33.130 --> 00:46:35.489
from the start. But the big emphasis in early

00:46:35.489 --> 00:46:37.869
rehab, according to the sources, is on closed

00:46:37.869 --> 00:46:41.230
chain exercises. Closed chain. What exactly are

00:46:41.230 --> 00:46:43.949
those and why are they preferred early on? Closed

00:46:43.949 --> 00:46:45.909
chain means exercises where the foot is fixed

00:46:45.909 --> 00:46:48.190
or planted on a surface, like mini squats, leg

00:46:48.190 --> 00:46:50.969
presses, or step ups. These exercises tend to

00:46:50.969 --> 00:46:52.929
generate compressive forces across the knee joint

00:46:52.929 --> 00:46:55.190
and are thought to put less direct shear stress

00:46:55.190 --> 00:46:57.670
on the ACL graph compared to open chain exercises.

00:46:58.230 --> 00:47:00.309
The sources specifically advise avoiding open

00:47:00.309 --> 00:47:02.230
chain quadriceps strengthening in the initial

00:47:02.230 --> 00:47:05.570
phases of rehab. Open chain being exercises like

00:47:05.570 --> 00:47:08.070
the seated leg extension machine, where your

00:47:08.070 --> 00:47:11.199
foot moves freely in space. Precisely. That kind

00:47:11.199 --> 00:47:12.900
of exercise, especially straightening the knee

00:47:12.900 --> 00:47:14.960
against resistance in the last 30 degrees or

00:47:14.960 --> 00:47:17.559
so, effectively mimics the forces applied during

00:47:17.559 --> 00:47:20.719
the anterior drawer and lachman tests. It creates

00:47:20.719 --> 00:47:23.760
a significant anterior pull on the tibia, directly

00:47:23.760 --> 00:47:25.800
stressing the new graft exactly what you want

00:47:25.800 --> 00:47:27.940
to avoid while it's healing and incorporating.

00:47:28.380 --> 00:47:30.860
That makes perfect sense. Don't repeatedly do

00:47:30.860 --> 00:47:32.900
the movement that challenges the ligament you

00:47:32.900 --> 00:47:35.300
just fixed. Do the rules about open -chain exercises

00:47:35.300 --> 00:47:38.000
change later in rehab? This is where things get

00:47:38.000 --> 00:47:41.159
a bit more nuanced. As rehab progresses, the

00:47:41.159 --> 00:47:44.599
sources mention some updated evidence. Neuromuscular

00:47:44.599 --> 00:47:47.699
electrical stimulation, NMES, applied to the

00:47:47.699 --> 00:47:50.019
quads is highlighted as potentially beneficial,

00:47:50.539 --> 00:47:52.719
showing improvements in strength when added to

00:47:52.719 --> 00:47:55.489
standard rehab in the first few months. Regarding

00:47:55.489 --> 00:47:58.849
open kinetic chain, OKC, exercises like leg extensions,

00:47:59.610 --> 00:48:01.690
some more recent research cited suggests that

00:48:01.690 --> 00:48:04.130
when introduced appropriately later in rehab,

00:48:04.309 --> 00:48:06.630
for example, after four weeks, perhaps initially

00:48:06.630 --> 00:48:09.510
in a limited range like 45 -90 degrees, there

00:48:09.510 --> 00:48:11.769
might not be a significant detrimental effect

00:48:11.769 --> 00:48:14.469
on knee laxity, strength, or patient -reported

00:48:14.469 --> 00:48:16.909
function compared to solely sticking with closed

00:48:16.909 --> 00:48:19.909
chain exercises. This seems to hold true regardless

00:48:19.909 --> 00:48:22.170
of graft type. That's interesting. So maybe not

00:48:22.170 --> 00:48:23.849
completely forbidden later on if done carefully.

00:48:24.170 --> 00:48:26.110
What about where rehab takes place? Is going

00:48:26.110 --> 00:48:28.429
to a physio clinic inherently better than a structured

00:48:28.429 --> 00:48:31.289
home program? The sources suggest maybe not.

00:48:32.010 --> 00:48:34.630
Studies comparing structured supervised physiotherapy

00:48:34.630 --> 00:48:37.469
in a clinic versus equally structured home -based

00:48:37.469 --> 00:48:40.349
rehab programs haven't consistently shown one

00:48:40.349 --> 00:48:42.750
setting to be superior in terms of long -term

00:48:42.750 --> 00:48:45.329
outcomes for strength, knee laxity, or function.

00:48:45.500 --> 00:48:48.179
This implies that the quality and consistency

00:48:48.179 --> 00:48:50.539
of the program and the patient's adherence to

00:48:50.539 --> 00:48:52.639
it might be more important than the physical

00:48:52.639 --> 00:48:54.679
location where it's performed. That's useful

00:48:54.679 --> 00:48:56.559
information for patients potentially offering

00:48:56.559 --> 00:48:59.980
more flexibility. Does doing rehab before the

00:48:59.980 --> 00:49:03.139
surgery, prehab, make a difference? Yes. Preoperative

00:49:03.139 --> 00:49:05.239
rehabilitation, typically involving a few weeks

00:49:05.239 --> 00:49:07.579
of targeted exercises to improve muscle strength,

00:49:07.760 --> 00:49:09.639
activation, and neuromuscular control before

00:49:09.639 --> 00:49:12.940
the operation, is shown to have benefits. The

00:49:12.940 --> 00:49:15.039
sources state it can improve patient reported

00:49:15.039 --> 00:49:17.559
function and physical function scores in the

00:49:17.559 --> 00:49:19.920
first three months after surgery. However, it

00:49:19.920 --> 00:49:22.179
doesn't seem to significantly impact the ultimate

00:49:22.179 --> 00:49:24.719
time to return to sport, or the overall success

00:49:24.719 --> 00:49:27.059
rate of returning. So, it helps smooth out the

00:49:27.059 --> 00:49:29.440
early post -op phase, but doesn't necessarily

00:49:29.440 --> 00:49:32.400
speed up the final return. That brings us to

00:49:32.400 --> 00:49:34.500
the million dollar question for many, especially

00:49:34.500 --> 00:49:37.800
athletes. When can they actually get back to

00:49:37.800 --> 00:49:40.460
playing their sport? This is still a complex

00:49:40.460 --> 00:49:43.159
area, and the sources indicate there aren't universally

00:49:43.159 --> 00:49:45.800
agreed upon definitive criteria for timing the

00:49:45.800 --> 00:49:50.050
return to play. RTP. Historically, a common guideline

00:49:50.050 --> 00:49:53.269
was no sooner than nine months post -op. However,

00:49:53.630 --> 00:49:55.650
the focus is increasingly shifting towards meeting

00:49:55.650 --> 00:49:58.449
objective performance -based criteria rather

00:49:58.449 --> 00:50:01.030
than just relying on time alone. Meaning the

00:50:01.030 --> 00:50:04.099
athlete has to pass certain tests. Exactly. Clearance

00:50:04.099 --> 00:50:06.360
is often based on passing a battery of functional

00:50:06.360 --> 00:50:08.900
tests designed to assess strength, power, balance,

00:50:09.039 --> 00:50:11.280
and control during movements that simulate the

00:50:11.280 --> 00:50:13.400
demands of their sport. Things like single leg

00:50:13.400 --> 00:50:15.960
hop tests for distance and height, agility drills,

00:50:16.119 --> 00:50:17.940
and assessment of landing mechanics. And how

00:50:17.940 --> 00:50:20.429
they land is particularly important. Very important.

00:50:20.989 --> 00:50:23.750
The sources specifically highlight that returning

00:50:23.750 --> 00:50:26.150
to sport while still demonstrating poor movement

00:50:26.150 --> 00:50:29.030
patterns, like that dynamic valgus knee collapse

00:50:29.030 --> 00:50:32.070
during landing or cutting, significantly increases

00:50:32.070 --> 00:50:34.309
the risk of re -rupturing the graft or tearing

00:50:34.309 --> 00:50:37.210
the ACL in the other, previously uninjured knee.

00:50:38.000 --> 00:50:40.079
Consistently, higher rates of reinjury and graft

00:50:40.079 --> 00:50:42.960
failure are reported when athletes return prematurely

00:50:42.960 --> 00:50:45.019
before meeting appropriate functional and strength

00:50:45.019 --> 00:50:47.380
criteria. So impatience is a major risk factor

00:50:47.380 --> 00:50:49.699
for ending up back at square one. Who makes the

00:50:49.699 --> 00:50:51.980
final call on clearance? The decision should

00:50:51.980 --> 00:50:54.579
ideally be a collaborative one, the sources suggest,

00:50:55.079 --> 00:50:57.639
involving the surgeon, the physiotherapist, and

00:50:57.639 --> 00:51:00.360
the patient. It needs to consider not just the

00:51:00.360 --> 00:51:02.800
physical readiness demonstrated in testing, but

00:51:02.800 --> 00:51:05.699
also psychological factors. Fear of re -injury

00:51:05.699 --> 00:51:08.079
or lack of confidence can be significant barriers,

00:51:08.480 --> 00:51:10.519
even if the knee is physically strong. While

00:51:10.519 --> 00:51:13.139
the average RTP time frame is often quoted as

00:51:13.139 --> 00:51:16.420
6 to 12 months, a crucial point raised is that

00:51:16.420 --> 00:51:19.559
the biological process of graft healing, remodeling,

00:51:19.699 --> 00:51:22.000
and maturing into a strong ligament can take

00:51:22.000 --> 00:51:25.090
much longer, potentially 18 months or more. Returning

00:51:25.090 --> 00:51:27.570
before the graft is fully mature and the neuromuscular

00:51:27.570 --> 00:51:30.210
control is restored significantly increases the

00:51:30.210 --> 00:51:32.710
risk. That need for patients allowing the biology

00:51:32.710 --> 00:51:36.230
to catch up seems absolutely paramount. Now despite

00:51:36.230 --> 00:51:38.730
best efforts complications can still occur after

00:51:38.730 --> 00:51:41.510
ACL surgery. What are the main potential setbacks

00:51:41.510 --> 00:51:44.110
or problems mentioned in the sources? The single

00:51:44.110 --> 00:51:47.289
most common complication reported after ACL reconstruction

00:51:47.289 --> 00:51:50.250
is loss of knee motion. leading to stiffness

00:51:50.250 --> 00:51:53.550
or arthrofibrosis. The sources strongly correlate

00:51:53.550 --> 00:51:55.590
this risk with not having achieved full range

00:51:55.590 --> 00:51:58.590
of motion before the surgery. It typically presents

00:51:58.590 --> 00:52:00.610
as difficulty fully straightening or bending

00:52:00.610 --> 00:52:03.449
the knee and sometimes reduced mobility of the

00:52:03.449 --> 00:52:05.809
kneecap. How do they try and prevent stiffness

00:52:05.809 --> 00:52:08.789
and what's done if it does develop? Prevention

00:52:08.789 --> 00:52:11.269
hinges on that preoperative range of motion,

00:52:11.769 --> 00:52:13.789
waiting for the initial inflammation to settle

00:52:13.789 --> 00:52:17.050
before operating, and diligent post -op physiotherapy

00:52:17.050 --> 00:52:19.909
emphasizing early motion. particularly extension.

00:52:21.010 --> 00:52:23.150
Aggressive icing also helps manage swelling which

00:52:23.150 --> 00:52:25.710
can contribute to stiffness. If stiffness does

00:52:25.710 --> 00:52:27.849
become a problem, the initial approach is intensive

00:52:27.849 --> 00:52:30.809
physiotherapy, sometimes involving specific stretching

00:52:30.809 --> 00:52:33.449
techniques or serial splinting to gradually regain

00:52:33.449 --> 00:52:35.849
motion, especially within the first three months.

00:52:36.159 --> 00:52:38.480
If significant stiffness persists beyond that,

00:52:38.820 --> 00:52:40.719
a surgical procedure might be needed usually

00:52:40.719 --> 00:52:43.260
in arthroscopic lysis of adhesions where the

00:52:43.260 --> 00:52:45.380
scar tissue is released, often combined with

00:52:45.380 --> 00:52:47.699
a manipulation under anesthesia to physically

00:52:47.699 --> 00:52:50.400
push the knee through its range. Stiffness sounds

00:52:50.400 --> 00:52:53.139
like a frustrating complication. What about problems

00:52:53.139 --> 00:52:55.360
with the graft itself? What's the most common

00:52:55.360 --> 00:52:57.699
reason for the actual reconstruction to fail?

00:52:58.019 --> 00:53:01.119
Tunnel mount position. The sources are very clear

00:53:01.119 --> 00:53:03.820
that drilling the bone tunnels in a non -anatomical

00:53:03.820 --> 00:53:07.019
location is the leading cause of technical failure

00:53:07.019 --> 00:53:09.400
of the graft, accounting for potentially up to

00:53:09.400 --> 00:53:11.840
70 % of failures where the surgery itself is

00:53:11.840 --> 00:53:15.099
the issue. The overall graft failure rate requiring

00:53:15.099 --> 00:53:18.179
revision surgery is estimated around 5 -10 %

00:53:18.179 --> 00:53:20.239
depending on the population. And what are the

00:53:20.239 --> 00:53:22.579
consequences of those tunnels being in the wrong

00:53:22.579 --> 00:53:25.340
place? It depends on the error. For example,

00:53:25.340 --> 00:53:27.760
if the femoral tunnel is too vertical, a common

00:53:27.760 --> 00:53:30.260
historical issue with older techniques, the graft

00:53:30.260 --> 00:53:32.619
might stop forward sliding but fail to control

00:53:32.619 --> 00:53:36.039
rotation, leading to persistent instability during

00:53:36.039 --> 00:53:39.239
pivoting a positive pivot shift test. If the

00:53:39.239 --> 00:53:41.460
tibial tunnel is too far forward, the graft can

00:53:41.460 --> 00:53:43.940
get pinched or impinged by the roof of the intercondylar

00:53:43.940 --> 00:53:46.639
notch when the knee straightens, causing pain,

00:53:46.980 --> 00:53:49.139
swelling, and potentially limiting extension

00:53:49.139 --> 00:53:52.500
or damaging the graft over time. Even small errors

00:53:52.500 --> 00:53:54.920
in placement can compromise the graft's function.

00:53:55.119 --> 00:53:57.820
So that surgical precision we discussed is truly

00:53:57.820 --> 00:54:00.420
fundamental to avoiding the most common failure

00:54:00.420 --> 00:54:03.380
mechanism. Are there other reasons a graft might

00:54:03.380 --> 00:54:06.099
fail besides being put in the wrong spot? Yes,

00:54:06.380 --> 00:54:08.559
several other causes are mentioned. Fixation

00:54:08.559 --> 00:54:10.960
failure, the screws, buttons, or other devices

00:54:10.960 --> 00:54:13.039
might loosen, break, or not hold the graft securely

00:54:13.039 --> 00:54:15.679
enough. Graft tunnel mismatch can occur, for

00:54:15.679 --> 00:54:18.699
example, if a BPTB graft's bone plugs are too

00:54:18.699 --> 00:54:21.280
long for the tunnels drilled. A traditional failure

00:54:21.280 --> 00:54:23.380
might happen if the graft tissue itself was too

00:54:23.380 --> 00:54:26.079
thin or weak to begin with, EHEA hamstring graft

00:54:26.079 --> 00:54:30.099
under 8mm diameter. In BPTV grafts, the bone

00:54:30.099 --> 00:54:31.920
plug itself could technically dislodge within

00:54:31.920 --> 00:54:35.059
the joint. A major cause is failure to diagnose

00:54:35.059 --> 00:54:36.940
and treat associated injuries at the time of

00:54:36.940 --> 00:54:39.159
the initial surgery. If significant damage to

00:54:39.159 --> 00:54:41.820
the PCL or post -verlateral corner is missed,

00:54:42.340 --> 00:54:45.000
the ACL graft will be overloaded and likely fail

00:54:45.000 --> 00:54:48.190
over time. Improper or overly aggressive rehabilitation,

00:54:48.489 --> 00:54:50.250
particularly those open -chain exercises too

00:54:50.250 --> 00:54:52.710
early, can also contribute. And certain patient

00:54:52.710 --> 00:54:54.489
factors are associated with higher failure risk,

00:54:54.710 --> 00:54:56.769
like being very young, having significant pre

00:54:56.769 --> 00:54:59.030
-existing knee hyperextension, returning to high

00:54:59.030 --> 00:55:01.449
-risk sports very quickly, or having anatomical

00:55:01.449 --> 00:55:03.530
factors like a steep posterior tibial slope.

00:55:03.730 --> 00:55:05.809
It's clearly a complex interplay of surgical

00:55:05.809 --> 00:55:08.750
technique, biology, rehabilitation, and patient

00:55:08.750 --> 00:55:11.789
factors. What about infection after the surgery?

00:55:11.889 --> 00:55:14.960
Is that common? Thankfully, joint infection,

00:55:15.219 --> 00:55:17.900
or septic arthritis, is a serious but relatively

00:55:17.900 --> 00:55:20.719
rare complication, occurring in less than 1 %

00:55:20.719 --> 00:55:23.119
of primary ACL reconstructions according to the

00:55:23.119 --> 00:55:25.880
sources. It's usually caused by common skin bacteria

00:55:25.880 --> 00:55:29.340
like staph epidermidis or staph aureus. It typically

00:55:29.340 --> 00:55:31.360
shows up within the first few weeks post -op

00:55:31.360 --> 00:55:35.360
with increasing pain, swelling, warmth, redness,

00:55:35.760 --> 00:55:38.199
and potentially systemic signs like fever. How

00:55:38.199 --> 00:55:40.500
is an infection treated? Does it mean the graft

00:55:40.500 --> 00:55:43.699
is lost? Diagnosis involves taking a fluid sample

00:55:43.699 --> 00:55:46.199
from the knee joint. Treatment needs to be prompt

00:55:46.199 --> 00:55:49.119
and aggressive. Usually a media arthroscopic

00:55:49.119 --> 00:55:51.659
surgery to thoroughly wash out the joint, combined

00:55:51.659 --> 00:55:53.679
with intravenous antibiotics for an extended

00:55:53.679 --> 00:55:57.000
period, typically at least six weeks. The sources

00:55:57.000 --> 00:55:59.199
suggest that with this approach, especially if

00:55:59.199 --> 00:56:01.239
caught early and depending on the bacteria involved,

00:56:01.699 --> 00:56:03.820
the graft can sometimes be successfully retained.

00:56:03.980 --> 00:56:05.840
It doesn't automatically mean the reconstruction

00:56:05.840 --> 00:56:08.500
has failed, but it requires significant intervention.

00:56:08.679 --> 00:56:12.300
So treatable but requires swift action. Are there

00:56:12.300 --> 00:56:14.760
any other specific complications worth mentioning

00:56:14.760 --> 00:56:17.559
that appear in the sources? Yes, a few others

00:56:17.559 --> 00:56:20.460
are listed. Infrapatellar contracture syndrome

00:56:20.460 --> 00:56:22.980
is a specific rare type of stiffness involving

00:56:22.980 --> 00:56:25.880
scar tissue forming below the kneecap. Patellar

00:56:25.880 --> 00:56:28.059
tendon rupture or patella fracture can occur

00:56:28.059 --> 00:56:31.440
usually months after surgery if a BPTB or quad

00:56:31.440 --> 00:56:34.539
tendon graft with a bone block was used. Complex

00:56:34.539 --> 00:56:37.719
regional pain syndrome, CRPS, previously known

00:56:37.719 --> 00:56:40.960
as RSD, is another potential but uncommon pain

00:56:40.960 --> 00:56:44.699
complication. Tunnel osteolysis gradual widening

00:56:44.699 --> 00:56:47.260
of the bone tunnel seen on x -ray can occur over

00:56:47.260 --> 00:56:49.960
time, but usually only needs monitoring unless

00:56:49.960 --> 00:56:53.059
it causes graft loosening. Long -term, the risk

00:56:53.059 --> 00:56:56.000
of developing late osteoarthritis is real, particularly

00:56:56.000 --> 00:56:57.980
if there was significant meniscus or cartilage

00:56:57.980 --> 00:57:00.380
damage initially, or in patients who are older

00:57:00.380 --> 00:57:03.619
at the time of surgery. Nerve irritation, specifically

00:57:03.619 --> 00:57:05.860
branches of the saphenous nerve near the hamstring

00:57:05.860 --> 00:57:08.380
harvest site, can cause numbness or tingling

00:57:08.380 --> 00:57:11.860
on the shin. And finally, a cyclops lesion is

00:57:11.860 --> 00:57:13.820
a nodule of scar tissue that can form in the

00:57:13.820 --> 00:57:16.119
front of the knee after surgery and physically

00:57:16.119 --> 00:57:18.500
block the last few degrees of extension, sometimes

00:57:18.500 --> 00:57:21.099
causing a noticeable click or clunk. That's quite

00:57:21.099 --> 00:57:23.159
a comprehensive list of potential bumps in the

00:57:23.159 --> 00:57:25.340
road, reinforcing that recovery isn't always

00:57:25.340 --> 00:57:28.570
smooth sailing. Indeed. While the overall success

00:57:28.570 --> 00:57:31.110
rate is high, surgeons and patients need to be

00:57:31.110 --> 00:57:33.400
aware of these potential issues. Okay, let's

00:57:33.400 --> 00:57:35.679
move to our final section, section six. Looking

00:57:35.679 --> 00:57:38.000
at the long -term outlook and injury prevention,

00:57:38.380 --> 00:57:40.420
we've already discussed the risks of not treating

00:57:40.420 --> 00:57:44.079
an ACL tear the progressive damage. What's the

00:57:44.079 --> 00:57:47.320
general prognosis with treatment, with reconstruction,

00:57:47.760 --> 00:57:49.699
according to the sources? The sources generally

00:57:49.699 --> 00:57:52.639
portray the natural history of an untreated ACL

00:57:52.639 --> 00:57:55.099
deficient knee as one leading towards accelerated

00:57:55.099 --> 00:57:57.579
arthritis and further joint damage due to the

00:57:57.579 --> 00:58:00.550
chronic instability. However, with a successful

00:58:00.550 --> 00:58:02.969
surgical reconstruction followed by thorough

00:58:02.969 --> 00:58:05.590
and appropriate rehabilitation, the prognosis

00:58:05.590 --> 00:58:08.469
is typically described as good. The aim is to

00:58:08.469 --> 00:58:10.429
restore knee stability and function very close

00:58:10.429 --> 00:58:12.969
to its pre -injury state, enabling a high level

00:58:12.969 --> 00:58:15.650
of return to activity and sport for most patients.

00:58:15.929 --> 00:58:18.150
That's certainly positive news for those facing

00:58:18.150 --> 00:58:20.349
this injury and the subsequent recovery journey.

00:58:20.570 --> 00:58:23.050
Now, considering everything we've discussed,

00:58:23.150 --> 00:58:25.130
the specific ways these injuries happen, the

00:58:25.130 --> 00:58:27.389
risk factors like biomechanics and neuromuscular

00:58:27.389 --> 00:58:30.349
control, especially in female athletes, the challenges

00:58:30.349 --> 00:58:33.070
of recovery, including re -injury risk, do the

00:58:33.070 --> 00:58:35.349
sources talk much about preventing ACL tears

00:58:35.349 --> 00:58:37.849
from happening in the first place? Yes, absolutely.

00:58:38.530 --> 00:58:40.750
Injury prevention is a significant focus in the

00:58:40.750 --> 00:58:42.809
literature reviewed, particularly prevention

00:58:42.809 --> 00:58:45.670
programs aimed at athletes, and with a specific

00:58:45.670 --> 00:58:48.289
emphasis on female athletes due to that higher

00:58:48.289 --> 00:58:51.230
risk profile we discussed. The cornerstone of

00:58:51.230 --> 00:58:53.309
these prevention strategies is neuromuscular

00:58:53.309 --> 00:58:55.869
training and plyometrics. Neuromuscular training

00:58:55.869 --> 00:58:58.849
and plyometrics. So exercises focusing on jumping,

00:58:59.230 --> 00:59:01.269
landing, and coordination. What's the underlying

00:59:01.269 --> 00:59:04.269
principle? Exactly. It involves specific exercises

00:59:04.269 --> 00:59:06.630
designed to improve the communication and coordination

00:59:06.630 --> 00:59:08.730
between the brain and the muscles that control

00:59:08.730 --> 00:59:11.489
the knee and hip. The goal is to retrain movement

00:59:11.489 --> 00:59:13.789
patterns, teaching athletes, for example, to

00:59:13.789 --> 00:59:16.190
land softer, with more bend at the knees and

00:59:16.190 --> 00:59:18.989
hips to absorb shock, and crucially, to avoid

00:59:18.989 --> 00:59:21.510
letting the knee collapse inwards into that risky,

00:59:21.710 --> 00:59:24.929
valgus position. It also often includes strengthening

00:59:24.929 --> 00:59:27.670
exercises, particularly for the hamstrings and

00:59:27.670 --> 00:59:29.690
glutes, to improve the muscle balance around

00:59:29.690 --> 00:59:32.349
the knee and reduce quadriceps dominance. So

00:59:32.349 --> 00:59:35.610
it's really about actively training safer ways

00:59:35.610 --> 00:59:38.050
to move to make the knee more resilient during

00:59:38.050 --> 00:59:40.789
those high -risk maneuvers. Are there other prevention

00:59:40.789 --> 00:59:43.730
tips mentioned? For skiers specifically, the

00:59:43.730 --> 00:59:45.570
sources mentioned that teaching proper falling

00:59:45.570 --> 00:59:48.449
techniques can help reduce injury risk. Regarding

00:59:48.449 --> 00:59:50.889
knee braces for prevention, the general consensus

00:59:50.889 --> 00:59:52.750
from the sources is that there's no convincing

00:59:52.750 --> 00:59:54.889
evidence that wearing a brace prevents an initial

00:59:54.889 --> 00:59:58.309
ACL injury in healthy athletes. The only potential

00:59:58.309 --> 01:00:00.289
exception mentioned is for skiers who already

01:00:00.289 --> 01:00:03.090
have an ACL deficiency, where a brace might provide

01:00:03.090 --> 01:00:05.949
some benefit. So proactive training focused on

01:00:05.949 --> 01:00:08.050
movement quality seems far more effective than

01:00:08.050 --> 01:00:10.170
relying on external equipment for prevention.

01:00:10.349 --> 01:00:12.690
That's certainly the message that comes through

01:00:12.690 --> 01:00:14.849
from the evidence presented in these sources.

01:00:14.969 --> 01:00:17.630
Well, this has been an incredibly detailed exploration

01:00:17.630 --> 01:00:20.690
of ACL injuries. We've gone from the basic anatomy,

01:00:20.829 --> 01:00:22.610
the different bundles within the ligament right

01:00:22.610 --> 01:00:25.250
through to the complex biomechanics of how tears

01:00:25.250 --> 01:00:28.429
happen, the diagnostic process, the critical

01:00:28.429 --> 01:00:30.429
decisions around surgery versus non -surgical

01:00:30.429 --> 01:00:33.309
management, the intricacies of different reconstructions,

01:00:33.099 --> 01:00:35.920
techniques and graphs, the long and demanding

01:00:35.920 --> 01:00:39.000
path of rehab, potential complications, and finally

01:00:39.000 --> 01:00:42.019
the prospects for prevention. We've really unpacked

01:00:42.019 --> 01:00:44.239
what these orthopedic resources reveal about

01:00:44.239 --> 01:00:47.159
this very common yet very significant knee injury.

01:00:47.420 --> 01:00:50.360
I think the key takeaways are understanding those

01:00:50.360 --> 01:00:53.739
non -contact mechanisms, recognizing the risk

01:00:53.739 --> 01:00:56.460
factors, particularly around neuromuscular control

01:00:56.460 --> 01:00:59.920
and landing mechanics, appreciating why precise

01:00:59.920 --> 01:01:02.780
surgical technique is so vital if reconstruction

01:01:02.780 --> 01:01:06.119
is undertaken, and acknowledging that comprehensive

01:01:06.119 --> 01:01:09.280
evidence -based rehabilitation, including addressing

01:01:09.280 --> 01:01:12.019
psychological factors, is absolutely essential

01:01:12.019 --> 01:01:14.099
for a successful outcome. It certainly paints

01:01:14.099 --> 01:01:16.519
a clear picture of the journey someone faces

01:01:16.519 --> 01:01:19.320
after hearing that pop all the way through to

01:01:19.320 --> 01:01:21.760
hopefully getting back to full activity. It highlights

01:01:21.760 --> 01:01:24.179
the biological, mechanical, and psychological

01:01:24.179 --> 01:01:27.400
challenges involved, definitely. And if you,

01:01:27.480 --> 01:01:30.159
our listener, have found this deep dive informative

01:01:30.159 --> 01:01:32.519
and valuable, we'd be very grateful if you could

01:01:32.519 --> 01:01:34.659
take a moment to rate and share the show. It

01:01:34.659 --> 01:01:36.619
really helps more people discover these insights.

01:01:36.920 --> 01:01:39.000
And perhaps as a final thought to leave you with,

01:01:39.639 --> 01:01:41.159
considering everything we've discussed today,

01:01:41.400 --> 01:01:44.239
The strong links between how we move, our muscle

01:01:44.239 --> 01:01:46.840
control, even our mental readiness, and both

01:01:46.840 --> 01:01:49.860
the risk of getting an ACL injury and the success

01:01:49.860 --> 01:01:53.019
of recovering from one, plus the ongoing challenge

01:01:53.019 --> 01:01:56.619
of re -injury. How much potential lies beyond

01:01:56.619 --> 01:01:59.539
just surgical repair? How might a much greater

01:01:59.539 --> 01:02:01.840
society -wide emphasis on mastering movement,

01:02:02.400 --> 01:02:04.579
implementing proactive injury prevention focused

01:02:04.579 --> 01:02:07.719
on biomechanics from a young age, and fully integrating

01:02:07.719 --> 01:02:10.239
psychological preparation into athletic development

01:02:10.239 --> 01:02:12.840
truly change the landscape for athlete health

01:02:12.840 --> 01:02:15.219
and longevity in the future? That's a powerful

01:02:15.219 --> 01:02:17.199
question to ponder. Thank you for joining us

01:02:17.199 --> 01:02:19.019
on the Deep Dive for this comprehensive look

01:02:19.019 --> 01:02:22.019
at ACL injuries. We trust you leave feeling significantly

01:02:22.019 --> 01:02:24.139
more informed about this prevalent and complex

01:02:24.139 --> 01:02:24.440
issue.