WEBVTT

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Imagine a tiny bone in your wrist, no bigger

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than a sugar cube, suddenly losing its lifeline,

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its blood supply. Hmm. What happens then isn't

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just a simple sprain or a minor ache. It's a

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journey into chronic pain, progressive stiffness,

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and actually a surprisingly complex medical condition

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we're diving deep into today. Indeed. We're talking

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about Kinvox disease, a condition that, at its

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core, involves the vascular necrosis, or you

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might hear osteonecrosis, of the lunate bone

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in the wrist. Lunatomalacia is another term you

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might come across. Right, lunatomalacia. It's

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a rare condition, often quite insidious, initially

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mimicking far less serious problems, which must

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make diagnosing it a significant challenge. Exactly.

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And our exploration today isn't just a general

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overview, it's a deep dive, specifically tailored

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to the source materials you provided, a stack

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of articles, research papers, excerpts from various

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medical resources like StatPearls, OrthoBullets,

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the Hand Society, and others, all focusing on

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this specific condition. OK, so our mission,

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leveraging these resources, is to extract the

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most important, insightful information. We want

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to understand precisely what Kinbach's disease

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is, maybe unravel the mystery of why it happens,

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given there seems to be no single cause. That's

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a key point. It's multifactorial. Right. And

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identify who it typically affects, delve into

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how medical professionals diagnose and stage

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its progression using different imaging techniques.

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Which is crucial for treatment. Absolutely. and

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explore the range of treatment options available,

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from non -surgical approaches right through to

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quite complex procedures, and critically understand

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what the long -term outlook and potential future

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holds for someone living with this condition.

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It's really about turning dense medical information

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into clear, actionable understanding for you

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listening. Think of it as your essential guide

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to becoming well -informed about Kinbach's disease,

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extracting the core knowledge and key considerations

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directly from the expert literature we've looked

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at. OK, let's unpack this. Let's start with the

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anatomy and the star of our deep dive. That tiny

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bone, the lunate. The lunate, yes. So this whole

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condition revolves around the lunate bone. Where

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exactly is it located, and why is it such a crucial

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player in the wrist's mechanics? Well, the lunate

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holds a really central and critical position

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in the wrist structure. It sits squarely in the

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middle of the proximal purple row. That's the

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first line of eight small carpal bones in your

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wrist, the ones closest to your forearm. OK.

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Its neighbors are the scaphoid on the thumb side

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and the trichotrum on the pinky side, with the

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pisiform sort of sitting on the trichotrum. More

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importantly, it articulates or connects directly

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with the two long bones of your forearm, the

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radius and the ulna. How does it connect to both?

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It connects specifically through the radial side

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and then via the triangular fibrocartilage complex

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or TFCC on the ulnar side. So it's literally

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right there bridging the forearm and the hand.

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What does that central position mean for its

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function? It means it's absolutely fundamental

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to wrist movement and load bearing. The lunidate

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acts as a key intermediary. You know, facilitating

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the complex range of motion we have in our wrists,

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flexion, bending down, extension, bending back,

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and to some extent, that side -to -side deviation

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as well. And the load -bearing aspect. Yes. Perhaps

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its most significant role, and one that's highly

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relevant to Kinbach's disease, is its function

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in absorbing and transmitting the forces that

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travel through your hand and wrist. particularly

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during activities like gripping, lifting, or

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bearing weight on your hands. Right. That makes

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sense. Our sources actually provide some fascinating

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statistics on this load transmission. Approximately

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35 % of the axial load that goes through your

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wrist during these activities is transmitted

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directly through the articulation between the

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radius and the radial -lunate joint. 25%. And

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another 10 % goes through the TSCC to the ulna.

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So yeah, a significant portion of force, about

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a third, is concentrated right on this one small

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bone. 35 % of the source going through your wrist

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on a bone no bigger than a sugar cube. That sounds

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like an awful lot of stress for such a small

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structure. It is. It's no wonder that if something

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goes wrong here, the consequences can be significant.

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Precisely. And the history of understanding problems

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with this bone goes back further than you might

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think. While there were earlier observations,

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figures like Peste back in the 19th century,

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the specific condition we call Keenbok's disease

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was formally described by Robert Keenbok, an

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Austrian radiologist, in 1910. 1910. So we've

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been piecing together the puzzle of this lunate

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failure for well over a century. We have indeed.

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Who is typically affected by this condition.

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Is there a pattern in the patients diagnosed?

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The data from the sources does show a typical

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demographic profile, although it's not exclusive,

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of course. It predominantly affects males, generally

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within a relatively specific age range, most

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commonly between 20 and 40 years old. Younger

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men, mostly. Yes. And while it's considered a

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rare condition overall, within the category of

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a vascular necrosis affecting the carpal bones,

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it's the second most common type after AVN of

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the scaphoid bone. OK, second only to the scaphoid.

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Correct. Interestingly, the sources also note

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that it's quite rare to see keen box disease

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affecting both wrists at the same time. It's

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usually unilateral, just one side. So younger

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to middle aged men are the most common demographic,

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though certainly not the only ones affected.

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Now, the big question and one the sources emphasize

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is still not fully answered. Why does this happen?

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Given the central role of blood supply loss,

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you'd think there'd be a clear cause. You would,

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wouldn't you? But the sources are clear there

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isn't one single consensus reason. It's described

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as multi -factorial. That's right. The mystery

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of Keenbox is that it seems to arise from a confluence

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of factors rather than a single event or deficiency.

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The sources detail several key proposed mechanisms

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that likely interact to lead to the disease.

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Okay, what are the main contenders? One of the

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most compelling and frequently cited is biomechanical

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imbalance. Specifically, variations in the lengths

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and angles of the bones in the forearm and wrist.

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The most prominent example is ulnar negative

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variance, often called ulna minuses. Okay, let's

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break that down. Ulnar negative variance, what

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does that actually look like in the wrist? Simply

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put, it means the ulna bone that's the forearm

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bone on the pinky side is congenitally shorter

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relative to the radius bone, the one on the thumb

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side. OK, shorter ulna. Because the radius is

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relatively longer. The load that should ideally

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be shared between the radius and the ulna. gets

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disproportionately shifted towards the radial

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side of the wrist. Ah, so the lunate, sitting

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mostly under the radius, ends up taking on an

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even greater share of that load than it normally

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would, more than that 35%. Exactly. That 35 %

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load transmission through the radial -lunate

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joint gets magnified. The sources cite studies

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showing a remarkably high correlation between

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Keenbach's disease and ulnar -negative variants,

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up to 78 % in some patient populations. 78%,

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that's huge. It is. that even a small anatomical

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difference in bone length can have a profound

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biomechanical consequence over time. Another

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related factor mentioned is a decreased radial

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inclination angle, which is the angle formed

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by the end of the radius bone. A lower angle

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here also seems to direct more force onto the

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lunate. It's fascinating how such subtle variations

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can predispose someone to this serious condition.

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What else contributes? Well, repetitive microtrauma

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and compression loading are also strongly implicated.

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While a single traumatic event can sometimes

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play a role, the sources emphasize that cumulative

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stress from repeated wrist movements, perhaps

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hyperextension, flexion, or significant axial

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loading. Like from certain jobs or sports? Precisely.

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Like from certain sports, manual trades, or even

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just repetitive heavy gripping. This can cause

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micro -damage to the lunate. Now, if this micro

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-damage outpaces the bone's ability to repair

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itself, it can compromise the local blood supply.

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So constant low -level stress, not necessarily

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a single big injury, could be part of the problem.

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You mentioned blood supply earlier. That seems

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absolutely fundamental to a vascular necrosis.

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It absolutely is. And the specific anatomy of

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the lunates' blood supply makes it particularly

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vulnerable. It receives blood from a network

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of small arteries that penetrate the bone from

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the dorsal, the back, and volar, the palm. sides

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of the wrist. These form anastomosis connections

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outside the bone. OK. But the crucial point highlighted

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in the sources is that the lunate has relatively

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sparse intraosseous collaterals. Meaning? Meaning

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there aren't many backup blood vessels running

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within the bone itself to provide alternative

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routes for blood flow if one of the main penetrating

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arteries gets compromised. So if a main supply

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line is blocked or damaged, there aren't many

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internal detours to keep the bone alive. That

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sounds like a significant point of vulnerability.

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It really is. And the sources specifically note

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that a lower number of these penetrating arteries,

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especially the vulgar branches coming from the

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palmar radiocarpal arch, is associated with an

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increased risk of developing kin box. Fewer entry

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points, more risk. Exactly. Different patterns

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of arterial supply have even been identified

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described as Y, X, or I patterns. The eye pattern,

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where there are fewer connections and less redundancy,

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is found in a significant proportion of patients,

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around 31%, and is postulated to be the most

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precarious in terms of blood supply. So the eye

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pattern might put those individuals at higher

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risk? Potentially, yes. The source has also mentioned

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the possibility of disruption to venous outflow,

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getting blood out of the bone. If that's impaired,

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it could lead to increased pressure within the

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bone, further compromising blood flow. Ah, so

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it's not just getting blood in, but also getting

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it out. Precisely. Venous outflow is part of

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the puzzle. So the lunid's blood supply is naturally

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a bit precarious, and if you have fewer main

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entry points or struggle to get blood out, it's

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a setup for potential failure. What about the

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bone's own structure or shape? Does that play

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a role? Yes. Lunate morphology is another piece

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of the puzzle. The size and shape of the lunate

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itself matter. Logically, a smaller lunate will

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experience higher stress per unit area under

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the same load. More significantly, perhaps, the

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shape plays a role. Lunates are often described

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as either more triangular, type 1, which lacks

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a medial, articular facet, or more square rectangular,

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type 3, which has that facet. The type I lunate

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is considered a risk factor because it seems

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to have a weaker internal trabecular pattern,

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making it potentially less resilient to stress.

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So, a combination of biomechanical stress from

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potentially misaligned forearm bones, repetitive

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microtrauma, a naturally fragile blood supply

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pattern, and maybe even a smaller or weaker shaped

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lunate bone. It really does sound like multiple

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risk factors converging to overwhelm this small

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bone. It's precisely that sort of perfect storm

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scenario that the sources point towards. And

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while a history of a single significant trauma

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is sometimes reported and can contribute, the

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sources emphasize that in a surprising number

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of cases, there's no clear traumatic event in

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the patient's history. The onset is often more

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gradual, more insidious. And are there any other

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medical conditions that seem to increase the

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risk? Any systemic links? Yes. The sources list

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several systemic conditions that are associated

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with Keenbox disease. These include conditions

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that might affect blood clotting or circulation,

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like sickle cell anemia, or inflammatory conditions

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like gout and lupus. Okay. Cerebral palsy is

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also mentioned, though the mechanism there might

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be related more to abnormal muscle forces affecting

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wrist mechanics. Osteoporosis, a condition causing

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weakened bones, particularly in older women,

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is also noted as a potential factor, though Keenbox

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is generally less common in that demographic

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compared to younger males. So these conditions

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might predispose someone by affecting the health

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of blood vessels or the bone tissue itself. That

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seems to be the thinking, yes. They add another

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layer of potential vulnerability. It's quite

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remarkable how seemingly unrelated systemic health

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issues can connect back to this problem in a

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tiny wrist bone. You touched on it briefly, but

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I've often heard Keenbox mentioned in the context

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of occupational hazards, like using vibrating

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tools. Does the research and the sources strongly

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support that link? That's a common association,

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certainly. And historically, occupational exposure,

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particularly to hand -arm vibration, was strongly

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suspected. However, the sources specifically

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highlight a systematic review which found, perhaps

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surprisingly, only weak evidence to definitively

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link Keenbox disease directly to occupational

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hand -arm vibration exposure. Oh really? Weak

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evidence? Yes. So while the idea of repetitive

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stress contributing is still very valid, the

00:12:40.370 --> 00:12:42.830
specific link to occupational vibration tools

00:12:42.830 --> 00:12:45.389
appears less strongly supported by current reviews

00:12:45.389 --> 00:12:48.049
than the sources than perhaps previously thought.

00:12:48.350 --> 00:12:51.009
This is a key point to note, as it does challenge

00:12:51.009 --> 00:12:53.190
a common assumption. Okay, so to sum up this

00:12:53.190 --> 00:12:56.090
complex etiology, it's rarely one single thing.

00:12:56.250 --> 00:12:58.710
It's more likely a combination of subtle individual

00:12:58.710 --> 00:13:01.149
anatomical variations, the mechanical demands

00:13:01.149 --> 00:13:03.929
placed on the wrist, a predisposed vascular architecture

00:13:03.929 --> 00:13:06.710
of the lunet, and potentially contributing systemic

00:13:06.710 --> 00:13:09.129
health issues. It's a fascinating interplay of

00:13:09.129 --> 00:13:12.230
factors. It truly is a multifactorial puzzle,

00:13:12.490 --> 00:13:14.769
and getting a handle on these potential contributors

00:13:14.769 --> 00:13:17.909
is crucial for diagnosis and deciding on treatment.

00:13:18.120 --> 00:13:20.720
even though the exact cause in any individual

00:13:20.720 --> 00:13:24.039
case can still be difficult to pinpoint definitively.

00:13:24.460 --> 00:13:26.360
And that difficulty brings us neatly to our next

00:13:26.360 --> 00:13:29.299
segment, experiencing this disease and the process

00:13:29.299 --> 00:13:31.779
of figuring out what's actually going on. Diagnosis

00:13:31.779 --> 00:13:34.399
and evaluation, yes. So someone is starting to

00:13:34.399 --> 00:13:38.039
feel pain in their wrist. How does Keenbox typically

00:13:38.039 --> 00:13:40.940
manifest from the patient's perspective? What

00:13:40.940 --> 00:13:43.500
are the common symptoms? Well, the sources describe

00:13:43.500 --> 00:13:45.799
a typical presentation that unfortunately often

00:13:45.799 --> 00:13:48.580
starts quite subtly. The most common initial

00:13:48.580 --> 00:13:51.320
symptom is pain, usually felt on the dorsal or

00:13:51.320 --> 00:13:53.440
back side of the wrist, right over where the

00:13:53.440 --> 00:13:56.240
lunate bone sits. Okay, dorsal wrist pain. Initially,

00:13:56.460 --> 00:13:58.519
this pain might be mild, intermittent, perhaps

00:13:58.519 --> 00:14:00.500
just feeling like a nagging ache after certain

00:14:00.500 --> 00:14:03.500
activities. It's very often dismissed as just

00:14:03.500 --> 00:14:06.019
a sprain or a minor strain, which contributes

00:14:06.019 --> 00:14:08.299
to that delay in diagnosis we mentioned earlier.

00:14:08.460 --> 00:14:10.860
So it's not usually a sudden, acute pain at the

00:14:10.860 --> 00:14:13.279
very beginning, like a fracture might be. Not

00:14:13.279 --> 00:14:16.059
typically, no. It's more often a gradual onset.

00:14:16.840 --> 00:14:19.200
The pain characteristically worsens with activities

00:14:19.200 --> 00:14:21.279
that put stress through the wrist, especially

00:14:21.279 --> 00:14:23.720
those involving wrist extension, bending it backwards,

00:14:24.179 --> 00:14:26.500
or significant axial loading. Like push -ups

00:14:26.500 --> 00:14:29.799
or lifting. Exactly. Things like push -ups, lifting

00:14:29.799 --> 00:14:32.960
heavy objects, or any task requiring strong gripping

00:14:32.960 --> 00:14:35.860
or leaning on the wrist. As the disease progresses

00:14:35.860 --> 00:14:38.659
and the bone degenerates, this activity -related

00:14:38.659 --> 00:14:41.620
discomfort can become more constant and debilitating,

00:14:41.940 --> 00:14:44.399
significantly impacting daily function. What

00:14:44.399 --> 00:14:47.659
else might someone experience? Beyond pain, other

00:14:47.659 --> 00:14:50.519
symptoms tend to emerge. On physical examination,

00:14:50.720 --> 00:14:52.960
a doctor might find localized swelling over the

00:14:52.960 --> 00:14:55.600
lunate area. There's almost always significant

00:14:55.600 --> 00:14:57.720
tenderness when pressing directly over the limate

00:14:57.720 --> 00:15:00.639
bone on the back of the wrist. Sinnovitis, which

00:15:00.639 --> 00:15:02.940
is inflammation of the joint lining, can also

00:15:02.940 --> 00:15:05.879
be present, contributing to the swelling and

00:15:05.879 --> 00:15:08.080
a feeling of stiffness. And what about the wrist

00:15:08.080 --> 00:15:10.840
movement? Does that get affected? Yes, range

00:15:10.840 --> 00:15:13.240
of motion becomes increasingly limited as the

00:15:13.240 --> 00:15:15.860
disease advances. You'll typically see a measurable

00:15:15.860 --> 00:15:18.940
decrease in both wrist flexion, bending down,

00:15:19.340 --> 00:15:22.659
and extension, bending back. Grip strength also

00:15:22.659 --> 00:15:25.299
diminishes, which makes sense given the lunate's

00:15:25.299 --> 00:15:27.720
role in load transmission during gripping. Okay,

00:15:27.919 --> 00:15:31.519
so pain, swelling, tenderness, stiffness, reduced

00:15:31.519 --> 00:15:34.139
grip. And in later stages, as the lunate bone

00:15:34.139 --> 00:15:36.399
begins to collapse and fragment and the overall

00:15:36.399 --> 00:15:38.879
carpal alignment changes, patients might start

00:15:38.879 --> 00:15:42.039
to notice mechanical symptoms, things like clicking,

00:15:42.320 --> 00:15:44.779
popping, or perhaps clunking sensations within

00:15:44.779 --> 00:15:46.919
the wrist during movement. Ah, that sounds like

00:15:46.919 --> 00:15:48.960
things are really starting to degenerate. It's

00:15:48.960 --> 00:15:50.919
often a sign of instability and advancing joint

00:15:50.919 --> 00:15:54.360
degeneration, yes. So it starts deceptively simply.

00:15:54.600 --> 00:15:57.919
but can progress to significant pain, stiffness,

00:15:58.419 --> 00:16:01.200
weakness, and even those mechanical noses. You

00:16:01.200 --> 00:16:03.100
mentioned earlier, though, that symptom severity

00:16:03.100 --> 00:16:05.320
doesn't always line up perfectly with the stage

00:16:05.320 --> 00:16:08.080
seen on imaging. That's a crucial point emphasized

00:16:08.080 --> 00:16:11.059
in the sources and one that makes managing expectations

00:16:11.059 --> 00:16:13.840
well. quite challenging. Yes, you can have someone

00:16:13.840 --> 00:16:16.980
experiencing severe debilitating pain early on,

00:16:17.139 --> 00:16:19.899
even when imaging only shows stage one or perhaps

00:16:19.899 --> 00:16:23.279
stage two changes. Really? Yes. Conversely, some

00:16:23.279 --> 00:16:25.759
individuals with radiographic evidence of more

00:16:25.759 --> 00:16:28.860
advanced stages might report surprisingly manageable

00:16:28.860 --> 00:16:31.779
pain levels for a period of time. This variability

00:16:31.779 --> 00:16:34.159
highlights the complex nature of pain perception

00:16:34.159 --> 00:16:37.700
and the disease's sometimes unpredictable clinical

00:16:37.700 --> 00:16:40.580
presentation. Given the subtle onset and that

00:16:40.580 --> 00:16:43.899
potential symptom stage mismatch, how do doctors

00:16:43.899 --> 00:16:46.379
go about diagnosing Keenbox disease? What's the

00:16:46.379 --> 00:16:48.940
investigative process? Diagnosis is fundamentally

00:16:48.940 --> 00:16:51.919
a clinical and imaging diagnosis. It starts with

00:16:51.919 --> 00:16:54.320
a detailed patient history, understanding when

00:16:54.320 --> 00:16:56.580
the symptoms began, what makes them worse, any

00:16:56.580 --> 00:16:59.120
history of trauma or repetitive activities, and

00:16:59.120 --> 00:17:01.039
reviewing any associated systemic conditions

00:17:01.039 --> 00:17:03.690
we talked about. The detective work. Exactly.

00:17:04.309 --> 00:17:06.970
Followed by a thorough physical examination to

00:17:06.970 --> 00:17:09.690
assess that tenderness, swelling, range of motion,

00:17:09.950 --> 00:17:13.130
and grip strength. But imaging is absolutely

00:17:13.130 --> 00:17:15.990
essential to confirm the diagnosis and, importantly,

00:17:16.430 --> 00:17:18.710
to stage the disease. Right, staging is key.

00:17:18.970 --> 00:17:21.529
How does the imaging usually proceed? The imaging

00:17:21.529 --> 00:17:24.740
process often follows a progression. Standard

00:17:24.740 --> 00:17:27.160
radiography x -rays are usually the first step.

00:17:27.519 --> 00:17:30.000
However, and this is a critical limitation, x

00:17:30.000 --> 00:17:32.000
-rays are often completely normal in the very

00:17:32.000 --> 00:17:34.839
early stages stage I. So a clear x -ray doesn't

00:17:34.839 --> 00:17:37.000
mean you're in the clear. Not at all, especially

00:17:37.000 --> 00:17:39.880
early on. The classic radiographic signs only

00:17:39.880 --> 00:17:42.349
appear later. What doctors look for in x -rays

00:17:42.349 --> 00:17:45.349
as the disease progresses are things like increased

00:17:45.349 --> 00:17:48.069
density of the lunate bone, sclerosis, which

00:17:48.069 --> 00:17:50.349
makes it appear whiter on the image due to hardening

00:17:50.349 --> 00:17:53.329
and attempted repair. Also cystic changes, small

00:17:53.329 --> 00:17:55.210
fluid -filled areas within the bone, obvious

00:17:55.210 --> 00:17:57.750
collapse or fragmentation of the lunate, changes

00:17:57.750 --> 00:17:59.630
in the alignment of the other carpal bones, what

00:17:59.630 --> 00:18:02.230
we call carpal collapse, and signs of secondary

00:18:02.230 --> 00:18:05.029
arthritis or arthrosis in the joints around the

00:18:05.029 --> 00:18:07.329
lunate. Do they need special x -ray views? Yes.

00:18:07.609 --> 00:18:10.809
X -rays are also needed in specific views, like

00:18:10.809 --> 00:18:13.950
a zero -rotation PA view, to accurately measure

00:18:13.950 --> 00:18:16.390
that ulnar variance we discussed earlier, as

00:18:16.390 --> 00:18:18.710
well as the radial inclination. They can also

00:18:18.710 --> 00:18:20.890
pick up coronal fractures within the lunate in

00:18:20.890 --> 00:18:23.970
later stages. So a normal X -ray definitely doesn't

00:18:23.970 --> 00:18:26.670
rule it out, especially early on. What's the

00:18:26.670 --> 00:18:29.390
next step in imaging, then, if the X -ray is

00:18:29.390 --> 00:18:32.430
normal but kin box is still suspected? Because

00:18:32.430 --> 00:18:35.700
X -rays are often normal initially, MRI magnetic

00:18:35.700 --> 00:18:38.160
resonance imaging, is considered the most sensitive

00:18:38.160 --> 00:18:41.400
diagnostic tool, particularly for detecting early

00:18:41.400 --> 00:18:43.619
-stage disease that isn't visible on x -rays,

00:18:43.660 --> 00:18:46.980
what we call radiographically occult cases. An

00:18:46.980 --> 00:18:49.619
MRI can directly visualize the changes in the

00:18:49.619 --> 00:18:52.240
bone marrow associated with loss of blood supply.

00:18:52.380 --> 00:18:54.900
What specifically does an MRI show in early -kin

00:18:54.900 --> 00:18:57.299
box? What's the giveaway? The hallmark finding

00:18:57.299 --> 00:19:00.279
on MRI, especially on T1 -weighted images, is

00:19:00.279 --> 00:19:02.619
a diffuse decrease in the signal intensity of

00:19:02.619 --> 00:19:04.900
the lunate bone marrow. This darkening of the

00:19:04.900 --> 00:19:06.799
bone marrow is indicative of disrupted blood

00:19:06.799 --> 00:19:08.980
flow and fat necrosis within the bone. Right,

00:19:09.059 --> 00:19:11.779
so the MRI sees the blood supply problem directly.

00:19:12.220 --> 00:19:14.900
Essentially, yes. As the disease progresses,

00:19:15.500 --> 00:19:17.559
the signal characteristics on other types of

00:19:17.559 --> 00:19:20.339
MRI sequences, like T2 -weighted or S -stora

00:19:20.339 --> 00:19:23.180
images, can change, reflecting things like edema,

00:19:23.480 --> 00:19:26.140
swelling, fragmentation, or those cystic changes.

00:19:26.769 --> 00:19:29.309
MRI is also invaluable for assessing the health

00:19:29.309 --> 00:19:31.509
of the surrounding cartilage and ligaments, helping

00:19:31.509 --> 00:19:34.190
to identify complications like scaffolding, ligament

00:19:34.190 --> 00:19:36.910
injury, or maybe ulnar impassioned syndrome,

00:19:37.230 --> 00:19:39.569
which can sometimes mimic or coexist with Keenbox.

00:19:40.190 --> 00:19:42.710
So MRI is key for catching it early by assessing

00:19:42.710 --> 00:19:45.029
blood supply and soft tissues. While x -rays

00:19:45.029 --> 00:19:47.210
are more useful for visualizing structural changes

00:19:47.210 --> 00:19:49.829
and overall alignment in later stages, what about

00:19:49.829 --> 00:19:52.509
CT scans? Where do they fit in? CTE computer

00:19:52.509 --> 00:19:54.769
tomography is particularly useful once structural

00:19:54.769 --> 00:19:57.670
damage is suspected or confirmed on x -ray, especially

00:19:57.670 --> 00:19:59.789
when surgical planning is being considered. CTE

00:19:59.789 --> 00:20:02.289
provides exquisite bony detail. Better than x

00:20:02.289 --> 00:20:04.829
-ray for bone detail. Oh, yes. It's more sensitive

00:20:04.829 --> 00:20:06.869
than x -ray for detecting subtle subchondral

00:20:06.869 --> 00:20:09.529
fractures. That's fractures just below the cartilage

00:20:09.529 --> 00:20:12.990
surface, any coronal lunate fractures, the precise

00:20:12.990 --> 00:20:15.529
degree of fragmentation of the lunate, and the

00:20:15.529 --> 00:20:18.430
extent of carpal instability patterns. The source

00:20:18.430 --> 00:20:20.230
has mentioned that patients are actually frequently

00:20:20.230 --> 00:20:23.630
restaged after getting a CT scan because it often

00:20:23.630 --> 00:20:26.130
reveals more extensive bony damage or instability

00:20:26.130 --> 00:20:28.630
than was apparent on the initial x -rays. Okay,

00:20:28.789 --> 00:20:31.349
so x -ray for general overview and alignment,

00:20:31.890 --> 00:20:34.170
MRI for early blood supply issues and soft tissue,

00:20:34.650 --> 00:20:37.910
and CT for detailed bone structure and fragmentation,

00:20:38.250 --> 00:20:40.630
especially important for surgery planning. Was

00:20:40.630 --> 00:20:42.650
there an older imaging technique used? Something

00:20:42.650 --> 00:20:45.230
else mentioned. Yes, nuclear scintigraphy. or

00:20:45.230 --> 00:20:47.809
a bone scan, was used historically as an adjunct

00:20:47.809 --> 00:20:50.250
tool, particularly for suspected early cases

00:20:50.250 --> 00:20:53.269
when MRI wasn't perhaps as widely available or

00:20:53.269 --> 00:20:55.849
sophisticated as it is today. It could show increased

00:20:55.849 --> 00:20:58.309
uptake in areas of bone injury or decreased uptake

00:20:58.309 --> 00:21:00.869
in areas of significant necrosis. But less common

00:21:00.869 --> 00:21:04.130
now. Much less common now. Given the superior

00:21:04.130 --> 00:21:06.670
sensitivity and the detailed anatomical information

00:21:06.670 --> 00:21:09.690
provided by MRI, bone scans have largely fallen

00:21:09.690 --> 00:21:13.069
out of favor for diagnosing Keenbox disease specifically.

00:21:13.509 --> 00:21:16.210
It sounds like Piecing together the diagnosis,

00:21:16.630 --> 00:21:19.809
especially in those crucial early stages, really

00:21:19.809 --> 00:21:22.529
requires a high index of suspicion and using

00:21:22.529 --> 00:21:25.430
the right imaging tools at the right time. It's

00:21:25.430 --> 00:21:27.849
easy to see how delays could happen. They are,

00:21:27.869 --> 00:21:30.670
unfortunately, very common. As the sources note,

00:21:30.809 --> 00:21:33.029
the challenge of early diagnosis is significant

00:21:33.029 --> 00:21:35.369
precisely because those initial symptoms are

00:21:35.369 --> 00:21:38.109
vague and x -rays are often normal, necessitating

00:21:38.109 --> 00:21:41.359
the use of MRI. Patients frequently experience

00:21:41.359 --> 00:21:43.539
diagnostic delays, sometimes for months or even

00:21:43.539 --> 00:21:46.140
years, which sadly allows the disease to progress

00:21:46.140 --> 00:21:48.859
further before any intervention. Once the diagnosis

00:21:48.859 --> 00:21:51.960
is made, how do doctors classify how severe the

00:21:51.960 --> 00:21:53.799
disease is? This is where staging comes in, right?

00:21:53.859 --> 00:21:55.960
You mentioned that's crucial. Correct. Staging

00:21:55.960 --> 00:21:58.099
is absolutely fundamental. It provides a framework

00:21:58.099 --> 00:21:59.940
for understanding the disease's progression,

00:21:59.940 --> 00:22:02.940
and most importantly, it guides treatment decisions.

00:22:03.259 --> 00:22:05.680
The most widely used system is morphologic staging

00:22:05.680 --> 00:22:08.200
based on the Lichtman classification. Lichtman

00:22:08.200 --> 00:22:11.339
classification. OK. This classification relies

00:22:11.339 --> 00:22:14.480
primarily on radiographic findings, mainly x

00:22:14.480 --> 00:22:17.640
-rays, often refined by CT. And it's known for

00:22:17.640 --> 00:22:20.180
its relatively low interobserver variability,

00:22:20.460 --> 00:22:22.500
meaning different clinicians tend to agree on

00:22:22.500 --> 00:22:24.420
the stage when looking at the images. What are

00:22:24.420 --> 00:22:26.819
the stages? The Lickman classification breaks

00:22:26.819 --> 00:22:29.779
down the progression of the lunates' deterioration

00:22:29.779 --> 00:22:31.880
and its effect on the surrounding wrist structure.

00:22:32.779 --> 00:22:36.079
Stage one. This is the earliest stage. Crucially,

00:22:36.619 --> 00:22:39.079
standard x -rays appear normal. The disease is

00:22:39.079 --> 00:22:41.640
only detectable at this point on MRI, which shows

00:22:41.640 --> 00:22:43.819
those characteristic signal changes indicating

00:22:43.819 --> 00:22:46.099
compromised blood supply, ischemia, and edema.

00:22:46.400 --> 00:22:49.740
So MRI positive, x -ray negative. Exactly. Stage

00:22:49.740 --> 00:22:53.160
two. Now, changes become visible on x -ray. The

00:22:53.160 --> 00:22:55.539
lunate shows increased density, or sclerosis.

00:22:55.539 --> 00:22:57.819
It looks whiter and more otake than normal bone.

00:22:58.480 --> 00:23:00.359
The overall shape and size of the lunand are

00:23:00.359 --> 00:23:02.359
still preserved at this stage, but subtle fraction

00:23:02.359 --> 00:23:04.000
lines might start to appear within the bone.

00:23:04.279 --> 00:23:07.460
Okay, density changes on x -ray? Yes. Stage 3.

00:23:07.759 --> 00:23:10.099
This is defined by collapse of the lunate's articular

00:23:10.099 --> 00:23:12.019
surface that smooths surface that connects with

00:23:12.019 --> 00:23:14.660
other bones. It's subdivided further. Stage 3

00:23:14.660 --> 00:23:17.420
-3. The lunate has collapsed, but the overall

00:23:17.420 --> 00:23:19.500
alignment and height of the carpal bones in the

00:23:19.500 --> 00:23:22.000
wrist are still preserved. No major structural

00:23:22.000 --> 00:23:25.279
shift yet. Stage 3 -4. The lunate collapse is

00:23:25.279 --> 00:23:27.660
more significant, and it starts leading to changes

00:23:27.660 --> 00:23:30.190
in carpal alignment. The scaphoid bone typically

00:23:30.190 --> 00:23:32.509
starts to flex forward, and there is a measurable

00:23:32.509 --> 00:23:35.269
loss of overall carpal height. This often results

00:23:35.269 --> 00:23:37.829
in a specific pattern of instability called the

00:23:37.829 --> 00:23:41.150
Dissy deformity, dorsal -interfilated segmental

00:23:41.150 --> 00:23:45.069
instability. Stage I. This is similar to I .B.

00:23:45.170 --> 00:23:47.289
with collapse and loss of carpal height, but

00:23:47.289 --> 00:23:49.670
specifically includes an associated coronal fracture

00:23:49.670 --> 00:23:52.150
of the fractal line visible on imaging running

00:23:52.150 --> 00:23:54.009
vertically through the bone. So stage III is

00:23:54.009 --> 00:23:55.730
all about collapse and its effect on alignment.

00:23:56.480 --> 00:23:59.619
Precisely. Then finally, stage four. This is

00:23:59.619 --> 00:24:03.059
the end stage. It includes the significant collapse

00:24:03.059 --> 00:24:05.880
and carpal height loss seen in stage IB, plus

00:24:05.880 --> 00:24:08.539
the development of secondary degenerative arthrosis,

00:24:09.319 --> 00:24:11.200
basically arthritis in the radiocarpal joint

00:24:11.200 --> 00:24:13.519
between the radius and the proximal carpal row,

00:24:14.079 --> 00:24:16.259
and or the mid -carpal joint between the two

00:24:16.259 --> 00:24:19.039
rows of carpal bones. So the lignum classification

00:24:19.039 --> 00:24:21.240
is essentially mapping the physical destruction

00:24:21.240 --> 00:24:24.039
of the bone and the cascade of effects on the

00:24:24.039 --> 00:24:26.480
rest of the wrist structure. Is there another

00:24:26.480 --> 00:24:29.059
way to stage the disease? You mentioned imaging

00:24:29.059 --> 00:24:31.359
blood flow earlier. Yes, there's also functional

00:24:31.359 --> 00:24:34.079
staging. This is typically assessed using contrast

00:24:34.079 --> 00:24:37.140
-enhanced MRI. While morphologic staging tells

00:24:37.140 --> 00:24:39.400
you about the structural damage, functional staging

00:24:39.400 --> 00:24:41.599
tells you about the actual blood flow and the

00:24:41.599 --> 00:24:43.680
extent of viable living bone tissue within the

00:24:43.680 --> 00:24:45.299
lunet. And that's important for treatment planning.

00:24:45.579 --> 00:24:48.000
Very much so. It's particularly valuable for

00:24:48.000 --> 00:24:50.480
guiding treatment decisions regarding revascularization

00:24:50.480 --> 00:24:52.920
procedures, which really only have a good chance

00:24:52.920 --> 00:24:55.519
of working if there's enough viable bone remaining.

00:24:55.680 --> 00:24:58.200
typically considered useful in stages first,

00:24:58.420 --> 00:25:01.319
two, and perhaps early stage theia. How does

00:25:01.319 --> 00:25:03.440
functional staging work with the contrast dye?

00:25:03.839 --> 00:25:06.579
Functional staging, based on how the lunate enhances

00:25:06.579 --> 00:25:08.880
after injecting contrast dye, looks something

00:25:08.880 --> 00:25:12.519
like this. Stage one. After the contrast injection,

00:25:12.839 --> 00:25:15.579
the lunate shows intense homogenous enhancement.

00:25:16.259 --> 00:25:18.839
This indicates good blood flow and viable bone,

00:25:19.200 --> 00:25:21.700
corresponding usually to morphologic stage I,

00:25:21.839 --> 00:25:24.349
where there's ischemia and edema. but not yet

00:25:24.349 --> 00:25:27.849
established necrosis. Stage 2. The enhancement

00:25:27.849 --> 00:25:31.029
is patchy and inhomogeneous. This suggests partial

00:25:31.029 --> 00:25:33.150
necrosis has occurred, but there are still areas

00:25:33.150 --> 00:25:35.589
of viable bone, often in the distal part of the

00:25:35.589 --> 00:25:38.349
lunate. This typically corresponds to morphologic

00:25:38.349 --> 00:25:41.589
stage 2, stage 3. There is a complete absence

00:25:41.589 --> 00:25:44.269
of contrast enhancement within the lunate. This

00:25:44.269 --> 00:25:47.230
indicates full -blown, complete avascular necrosis

00:25:47.230 --> 00:25:49.970
with no significant blood flow remaining, usually

00:25:49.970 --> 00:25:53.049
seen in morphologic stages 3a and beyond. So

00:25:53.049 --> 00:25:55.410
doctors use both morphologic staging to understand

00:25:55.410 --> 00:25:57.509
the structural damage and functional staging

00:25:57.509 --> 00:25:59.849
to understand the biological viability of the

00:25:59.849 --> 00:26:02.710
bone itself. That combined picture must be absolutely

00:26:02.710 --> 00:26:04.529
essential for deciding on the best course of

00:26:04.529 --> 00:26:07.170
action for each patient. It's precisely that

00:26:07.170 --> 00:26:09.710
comprehensive assessment that allows for tailoring

00:26:09.710 --> 00:26:12.690
treatment. Keenvox is definitely not a one -size

00:26:12.690 --> 00:26:14.769
-fits -all condition when it comes to management.

00:26:14.950 --> 00:26:17.069
Which leads us perfectly into the final piece

00:26:17.069 --> 00:26:19.660
of this puzzle. Navigating the treatment options

00:26:19.660 --> 00:26:21.700
and what the road ahead looks like for someone

00:26:21.700 --> 00:26:24.720
diagnosed with Keenbox disease. Yes, the management

00:26:24.720 --> 00:26:27.140
strategies. So we've mapped the disease's progression

00:26:27.140 --> 00:26:29.859
through staging. What are the main goals when

00:26:29.859 --> 00:26:32.539
doctors and patients discuss treatment for Keenbox?

00:26:32.599 --> 00:26:34.740
What are they trying to achieve? The fundamental

00:26:34.740 --> 00:26:37.000
goals of treatment, as outlined pretty consistently

00:26:37.000 --> 00:26:40.819
in the sources, are threefold. Alleviating pain,

00:26:41.220 --> 00:26:43.480
preserving as much wrist motion as possible,

00:26:43.779 --> 00:26:46.519
and maintaining or restoring grip strength. Pain,

00:26:46.579 --> 00:26:50.059
motion, strength. Makes sense. However, the strategy

00:26:50.059 --> 00:26:52.099
for achieving these goals is highly dependent

00:26:52.099 --> 00:26:55.119
on several factors. The specific stage of the

00:26:55.119 --> 00:26:57.119
disease, of course, based on Lickman and functional

00:26:57.119 --> 00:26:59.680
staging, the patient's symptoms and their functional

00:26:59.680 --> 00:27:02.420
demands, what they need their wrist to do, and

00:27:02.420 --> 00:27:04.700
crucially, the presence of those contributing

00:27:04.700 --> 00:27:07.700
biomechanical factors like ulnar negative variants.

00:27:08.160 --> 00:27:10.519
So treatment is very much tailored to the individual

00:27:10.519 --> 00:27:13.420
and their specific wrist anatomy and disease

00:27:13.420 --> 00:27:16.430
state. Absolutely. highly personalized. Let's

00:27:16.430 --> 00:27:18.930
start with the less invasive options. What happens

00:27:18.930 --> 00:27:21.430
in the earlier stages or perhaps for patients

00:27:21.430 --> 00:27:24.769
with milder symptoms? For early stage disease,

00:27:25.349 --> 00:27:27.710
typically stage one and potentially some cases

00:27:27.710 --> 00:27:30.250
of stage two where there's incomplete necrosis,

00:27:30.690 --> 00:27:32.730
non -operative approaches are usually considered

00:27:32.730 --> 00:27:36.150
initially. The most common method is immobilization

00:27:36.150 --> 00:27:39.299
of the wrist. usually with a cast or rigid splint.

00:27:39.660 --> 00:27:41.519
Immobilization. How long might someone need to

00:27:41.519 --> 00:27:44.400
be immobilized for? Does it vary? That duration

00:27:44.400 --> 00:27:46.980
varies quite significantly, as the sources highlight.

00:27:47.079 --> 00:27:49.880
While some studies report average immobilization

00:27:49.880 --> 00:27:52.920
periods around, say, 8 .6 months, historical

00:27:52.920 --> 00:27:55.220
accounts in the literature mention extremes of

00:27:55.220 --> 00:27:57.319
up to 20 years of casting, though that would

00:27:57.319 --> 00:27:59.599
be highly unusual in modern practice. Twenty

00:27:59.599 --> 00:28:02.880
years? Goodness. Yes. Immobilization is often

00:28:02.880 --> 00:28:05.039
the preferred initial treatment for specific

00:28:05.039 --> 00:28:07.920
demographics, such as adolescents, where bone

00:28:07.920 --> 00:28:09.940
healing potential might be different, and perhaps

00:28:09.940 --> 00:28:12.319
older adults over the age of 70, where surgical

00:28:12.319 --> 00:28:15.160
risks might be higher. Does embolization often

00:28:15.160 --> 00:28:18.279
lead to healing in adults? Does it fix the problem?

00:28:18.720 --> 00:28:20.539
Unfortunately, the sources are quite clear on

00:28:20.539 --> 00:28:23.960
this. In adults, spontaneous revascularization

00:28:23.960 --> 00:28:26.000
and healing of the lunate with non -operative

00:28:26.000 --> 00:28:28.940
treatment alone is rare. The disease is likely

00:28:28.940 --> 00:28:31.279
to progress to later stages despite prolonged

00:28:31.279 --> 00:28:33.839
casting in most adult cases. So it doesn't really

00:28:33.839 --> 00:28:36.769
stop it? Not usually in adults, no. A majority

00:28:36.769 --> 00:28:39.430
of adult patients initially treated nonoperatively

00:28:39.430 --> 00:28:42.009
will eventually require surgical intervention

00:28:42.009 --> 00:28:44.829
if they remain symptomatic, or the disease clearly

00:28:44.829 --> 00:28:48.349
advances on imaging. So, while immobilization

00:28:48.349 --> 00:28:50.589
might provide temporary pain relief by resting

00:28:50.589 --> 00:28:53.210
the wrist, it typically doesn't alter the underlying

00:28:53.210 --> 00:28:55.349
progressive course of the disease in adults.

00:28:55.529 --> 00:28:57.470
Okay, so it's more about symptom control, maybe?

00:28:57.809 --> 00:29:00.819
In many cases, yes. Other non -operative measures

00:29:00.819 --> 00:29:03.519
include pain management with simple analgesics

00:29:03.519 --> 00:29:06.579
like paracetamol or NSAIDs to reduce pain and

00:29:06.579 --> 00:29:09.440
swelling, and sometimes just observation combined

00:29:09.440 --> 00:29:11.980
with activity modification, advising patients

00:29:11.980 --> 00:29:14.299
to avoid activities that aggravate their pain.

00:29:15.359 --> 00:29:17.319
Again, while these can help manage symptoms,

00:29:17.680 --> 00:29:19.980
the sources indicate that most adult patients

00:29:19.980 --> 00:29:22.819
treated solely with observation or activity modification

00:29:22.819 --> 00:29:25.279
will eventually need more definitive management

00:29:25.279 --> 00:29:27.680
due to symptom progression or functional decline.

00:29:27.880 --> 00:29:30.500
Okay, so non -operative is mainly for symptom

00:29:30.500 --> 00:29:32.900
management, specific patient groups, or maybe

00:29:32.900 --> 00:29:35.200
as a holding measure. More often than not, it

00:29:35.200 --> 00:29:37.339
seems surgery becomes necessary. What are the

00:29:37.339 --> 00:29:39.480
main categories of surgical intervention, then?

00:29:40.019 --> 00:29:42.140
Operative treatment strategies broadly fall into

00:29:42.140 --> 00:29:44.420
two main categories, or sometimes a combination

00:29:44.420 --> 00:29:47.299
of both. One aims to restore blood supply to

00:29:47.299 --> 00:29:49.740
the lunate. These are the revascularization procedures.

00:29:50.029 --> 00:29:52.670
The other aims to reduce the mechanical load

00:29:52.670 --> 00:29:55.250
or stress on the lunate and stabilize the wrist.

00:29:55.769 --> 00:29:57.950
These are often called joint leveling or salvage

00:29:57.950 --> 00:30:00.130
procedures. Okay, let's talk about relieving

00:30:00.130 --> 00:30:01.930
the pressure first, the joint leveling ones.

00:30:02.170 --> 00:30:03.950
Right, these are the joint leveling procedures

00:30:03.950 --> 00:30:07.289
designed to offload the lunate. They're particularly

00:30:07.289 --> 00:30:09.509
relevant when that contributing factor of ulnar

00:30:09.509 --> 00:30:12.009
negative variance is present, but variations

00:30:12.009 --> 00:30:14.970
are also used for neutral or even positive variance

00:30:14.970 --> 00:30:17.910
situations. How does he do that? The most common

00:30:17.910 --> 00:30:20.789
procedure for significant ulna minus is a radial

00:30:20.789 --> 00:30:23.690
shortening osteotomy. This involves surgically

00:30:23.690 --> 00:30:25.670
removing a small segment of the radius bone to

00:30:25.670 --> 00:30:27.990
make it shorter, thus equalizing the lengths

00:30:27.990 --> 00:30:30.829
of the radius and ulna at the wrist joint and

00:30:30.829 --> 00:30:33.269
shifting load away from the lunate onto the ulnar

00:30:33.269 --> 00:30:35.750
side. Does she shorten the longer bone? Exactly.

00:30:36.470 --> 00:30:39.430
Alternatively, the less common and ulnar lengthening

00:30:39.430 --> 00:30:42.049
osteotomy can be performed to achieve the same

00:30:42.049 --> 00:30:45.309
relative length. For risks with neutral or positive

00:30:45.309 --> 00:30:47.470
ulnar variants, where the ulna is already the

00:30:47.470 --> 00:30:50.089
same length or longer, a radial wedge osteotomy

00:30:50.089 --> 00:30:53.150
can be used. This involves cutting a wedge shape

00:30:53.150 --> 00:30:55.450
out of the radius to alter the angle of the radial

00:30:55.450 --> 00:30:57.890
joint surface, again aiming to shift load off

00:30:57.890 --> 00:31:00.009
the lunate. So you're literally changing the

00:31:00.009 --> 00:31:02.549
bones alignment to create a better biomechanical

00:31:02.549 --> 00:31:05.329
environment for the struggling lunate. Do these

00:31:05.329 --> 00:31:07.650
procedures make a significant difference in how

00:31:07.650 --> 00:31:09.829
much stress the lunette actually bears? They

00:31:09.829 --> 00:31:12.250
can have a really dramatic effect. The sources

00:31:12.250 --> 00:31:15.529
cite some compelling data. A radial shortening

00:31:15.529 --> 00:31:17.890
or ulnar lengthening of just four millimeters

00:31:17.890 --> 00:31:21.250
can result in a substantial 45 percent decrease

00:31:21.250 --> 00:31:23.930
in the contact stress on the radial lunette joint.

00:31:24.550 --> 00:31:27.730
45%. That's huge. It is. This reduction in load

00:31:27.730 --> 00:31:29.690
provides a much better environment for potential

00:31:29.690 --> 00:31:31.890
healing, or at least slowing down progression,

00:31:32.470 --> 00:31:34.750
particularly useful in the earlier stages, typically

00:31:34.750 --> 00:31:38.190
stages 2 and higher IA. That's a massive reduction

00:31:38.190 --> 00:31:41.109
from a relatively small adjustment. Okay, what

00:31:41.109 --> 00:31:43.250
about the other approach, trying to bring blood

00:31:43.250 --> 00:31:45.509
flow back to the lunate, the revascularization

00:31:45.509 --> 00:31:47.630
you mentioned? Yes, these are the revascularization

00:31:47.630 --> 00:31:50.089
procedures. They are most appropriate in earlier

00:31:50.089 --> 00:31:52.990
stages, stages 5 and potentially early IDREA,

00:31:53.150 --> 00:31:54.970
when there is still a significant amount of viable

00:31:54.970 --> 00:31:57.410
bone remaining, which as we said can be assessed

00:31:57.410 --> 00:32:00.430
with that functional contrast MRI. The primary

00:32:00.430 --> 00:32:03.470
technique here is using vascularized bone grafts,

00:32:03.529 --> 00:32:06.569
VBG. Vascularized bone graft? What does that

00:32:06.569 --> 00:32:10.000
actually involve? Sounds complex. It is a complex

00:32:10.000 --> 00:32:12.619
microsurgical technique. It involves taking a

00:32:12.619 --> 00:32:14.660
bicep bone from another location in the body.

00:32:15.319 --> 00:32:17.380
Common donor sites include the distal radius

00:32:17.380 --> 00:32:20.440
itself, near the wrist, the iliac crest, which

00:32:20.440 --> 00:32:22.960
is part of the hip bone, or even using small

00:32:22.960 --> 00:32:25.539
bone pieces supplied by branches of the dorsal

00:32:25.539 --> 00:32:27.900
metacarpal arteries in the hand. Like the 4 plus

00:32:27.900 --> 00:32:30.759
5. Exactly. The 4 plus 5 extensor compartment

00:32:30.759 --> 00:32:33.019
artery pedicle is mentioned as being favored

00:32:33.019 --> 00:32:36.089
sometimes for its good mobility. Crucially, this

00:32:36.089 --> 00:32:38.410
bone piece is transferred with its attached blood

00:32:38.410 --> 00:32:41.630
vessels still intact and functioning. These kidney

00:32:41.630 --> 00:32:44.109
vessels are then surgically connected and astimosed

00:32:44.109 --> 00:32:46.730
to blood vessels near the lunate, effectively

00:32:46.730 --> 00:32:49.269
aiming to give the lunate a new, living blood

00:32:49.269 --> 00:32:51.650
supply and also some structural support. Bringing

00:32:51.650 --> 00:32:53.789
in reinforcements with their own supply lines?

00:32:53.950 --> 00:32:56.730
That's a good way to think of it. Another revascularization

00:32:56.730 --> 00:32:59.069
technique mentioned, often used in earlier stages,

00:32:59.309 --> 00:33:02.390
I5CDSE, is distal radius core decompression.

00:33:02.569 --> 00:33:05.549
This involves drilling small holes into the distal

00:33:05.549 --> 00:33:07.710
radius near the lunate attachment. Why drill

00:33:07.710 --> 00:33:10.250
holes? Well, the thinking is it might potentially

00:33:10.250 --> 00:33:13.170
reduce the pressure within the bone, the intraosseous

00:33:13.170 --> 00:33:15.970
pressure, and perhaps stimulate a local healing

00:33:15.970 --> 00:33:18.349
response and encourage the in -growth of new

00:33:18.349 --> 00:33:20.849
blood vessels from the radius towards the lunate.

00:33:21.450 --> 00:33:23.910
Sometimes, temporary pinning across the wrist

00:33:23.910 --> 00:33:27.829
or external fixation is used alongside revascularization

00:33:27.829 --> 00:33:31.089
to temporarily hold the wrist bones in a position

00:33:31.089 --> 00:33:33.529
that minimizes stress on the lunate, allowing

00:33:33.529 --> 00:33:35.690
the graft or decompression effect to establish.

00:33:35.930 --> 00:33:38.589
How successful are these? VBGs are certainly

00:33:38.589 --> 00:33:40.769
promising, especially in younger patients with

00:33:40.769 --> 00:33:43.769
early stage disease. However, the sources do

00:33:43.769 --> 00:33:45.769
note that long -term outcomes can be variable.

00:33:45.960 --> 00:33:49.059
And success really depends on the graft properly

00:33:49.059 --> 00:33:51.720
integrating and that new blood supply being sufficient

00:33:51.720 --> 00:33:54.319
and sustained. Okay, so leveling the bones to

00:33:54.319 --> 00:33:56.539
reduce stress or bringing in new blood supply

00:33:56.539 --> 00:33:58.900
with bone grafts. What happens when the lunate

00:33:58.900 --> 00:34:01.119
is already significantly collapsed or the wrist

00:34:01.119 --> 00:34:03.240
has become unstable or arthritic those later

00:34:03.240 --> 00:34:05.960
stages, IIB and IV? In these more advanced stages,

00:34:06.119 --> 00:34:08.360
the focus often shifts away from trying to save

00:34:08.360 --> 00:34:11.179
the lunated self towards salvage procedures.

00:34:11.780 --> 00:34:14.139
These aim to eliminate pain and stabilize the

00:34:14.139 --> 00:34:17.000
wrist, acknowledging that restoring full, normal

00:34:17.000 --> 00:34:20.139
motion may not be achievable. One category here

00:34:20.139 --> 00:34:23.840
is partial wrist fusions, arthrodesis. Partial

00:34:23.840 --> 00:34:26.179
fusion. What does that mean exactly? Fusing only

00:34:26.179 --> 00:34:29.079
some bones. Precisely. It means surgically fusing

00:34:29.079 --> 00:34:31.400
specific carpal bones together while leaving

00:34:31.400 --> 00:34:34.300
others free to move. The goal is usually to create

00:34:34.300 --> 00:34:37.679
stability. offload the damaged lunate area, or

00:34:37.679 --> 00:34:39.579
correct instability patterns like that dizzy

00:34:39.579 --> 00:34:41.780
deformity we mentioned, while hopefully preserving

00:34:41.780 --> 00:34:43.860
movement in the unfused portions of the wrist.

00:34:44.019 --> 00:34:46.619
Which bones might they fuse? Common partial fusions

00:34:46.619 --> 00:34:49.360
include STT fusion, which fuses the scaphoid,

00:34:49.460 --> 00:34:52.300
trapezium, and trapezoid bones together, or perhaps

00:34:52.300 --> 00:34:55.199
scaphocapitate fusion, or caponohamid fusion.

00:34:55.699 --> 00:34:57.940
These are typically considered in stages 2, LEIA,

00:34:58.099 --> 00:35:00.880
and IIB. What's the outcome of a partial fusion?

00:35:01.260 --> 00:35:03.579
Well, a partial fusion can certainly reduce pain

00:35:03.579 --> 00:35:06.300
and provide stability, but it necessarily limits

00:35:06.300 --> 00:35:08.599
the overall range of motion compared to a healthy

00:35:08.599 --> 00:35:11.539
wrist because the fused bones no longer move

00:35:11.539 --> 00:35:14.519
independently. The choice of which bones to fuse

00:35:14.519 --> 00:35:17.119
depends very much on the exact pattern of collapse

00:35:17.119 --> 00:35:20.119
and instability present. The sources do mention

00:35:20.119 --> 00:35:22.639
differing opinions and evidence regarding which

00:35:22.639 --> 00:35:25.480
specific partial fusion is optimal for, say,

00:35:25.619 --> 00:35:28.719
stage IB, with some studies suggesting STT fusion

00:35:28.719 --> 00:35:31.360
might be preferred over other options like proximal

00:35:31.360 --> 00:35:34.059
row carbectomy in certain cases. OK, so partial

00:35:34.059 --> 00:35:37.300
fusion limits motion but helps pain and stability.

00:35:38.000 --> 00:35:41.320
What if the lunate is severely fragmented, collapsed,

00:35:41.539 --> 00:35:44.039
or there's already significant arthritis involving

00:35:44.039 --> 00:35:46.510
that? whole first row of carpal bones. That's

00:35:46.510 --> 00:35:48.710
where proximal row carpectomy, PRC, becomes a

00:35:48.710 --> 00:35:50.929
very viable option. This involves surgically

00:35:50.929 --> 00:35:53.090
removing the entire proximal row of carpal bones,

00:35:53.409 --> 00:35:55.389
the scaphoid, the lunate, and the trichotrum.

00:35:55.550 --> 00:35:58.110
Removing all three. Yes. This procedure is typically

00:35:58.110 --> 00:36:00.650
indicated for stages I, IV, and IV, especially

00:36:00.650 --> 00:36:03.010
when the lunate is really beyond repair or the

00:36:03.010 --> 00:36:04.809
joints involving that proximal row are severely

00:36:04.809 --> 00:36:07.409
affected by arthritis. Removing three bones from

00:36:07.409 --> 00:36:10.150
the wrist sounds quite drastic. What's the outcome

00:36:10.150 --> 00:36:12.840
like after a PRC? While it sounds significant,

00:36:13.159 --> 00:36:15.400
PRC is actually a well -established procedure

00:36:15.400 --> 00:36:17.980
that can be very effective at relieving pain.

00:36:18.679 --> 00:36:21.380
It sacrifices that first row, but it preserves

00:36:21.380 --> 00:36:23.820
a surprising amount of wrist motion, usually

00:36:23.820 --> 00:36:27.219
around 50 -60 % of the normal range, by allowing

00:36:27.219 --> 00:36:29.599
the distal carpal row, the second row of bones,

00:36:30.119 --> 00:36:32.500
to articulate directly with the end of the radius

00:36:32.500 --> 00:36:34.940
bone. So you still get decent movement. You get

00:36:34.940 --> 00:36:37.139
functional movement, yes, and often good grip

00:36:37.139 --> 00:36:40.070
strength returns, too. This makes it a favorite

00:36:40.070 --> 00:36:42.110
option for individuals who need reasonable pain

00:36:42.110 --> 00:36:44.849
relief and still require a degree of wrist flexibility,

00:36:45.269 --> 00:36:47.170
perhaps for certain professions or activities

00:36:47.170 --> 00:36:49.110
like playing musical instruments. And if the

00:36:49.110 --> 00:36:51.769
arthritis is even more extensive, involving the

00:36:51.769 --> 00:36:54.670
radius itself or the entire wrist joint in stage

00:36:54.670 --> 00:36:57.829
4. When there is diffuse, severe arthritis throughout

00:36:57.829 --> 00:37:00.550
the radiocarpal and mid -carpal joints, often

00:37:00.550 --> 00:37:03.150
resulting from the end -stage collapse of Keenbach's

00:37:03.150 --> 00:37:06.730
disease, then a total wrist fusion orthodesis

00:37:06.730 --> 00:37:09.269
might be necessary. This is considered a definitive

00:37:09.269 --> 00:37:11.610
salvage procedure. Total fusion, what does that

00:37:11.610 --> 00:37:14.369
involve? Total wrist fusion involves surgically

00:37:14.369 --> 00:37:16.949
joining all the carpal bones together and then

00:37:16.949 --> 00:37:19.329
fusing this block of bones to the end of the

00:37:19.329 --> 00:37:21.349
radius bone in the forearm. So everything is

00:37:21.349 --> 00:37:24.630
locked solid? Essentially, yes. This procedure

00:37:24.630 --> 00:37:27.650
is extremely effective at eliminating pain because

00:37:27.650 --> 00:37:30.590
all the painful arthritic joints are immobilized.

00:37:30.929 --> 00:37:33.940
However, the trade -off is significant. You lose

00:37:33.940 --> 00:37:37.239
all notion at the wrist joint itself. No flexion,

00:37:37.300 --> 00:37:39.860
extension, or side -to -side deviation is possible.

00:37:40.519 --> 00:37:42.619
The hand is essentially fixed in a functional

00:37:42.619 --> 00:37:45.059
position relative to the forearm. Right, so you

00:37:45.059 --> 00:37:47.619
trade all wrist movement for complete pain relief

00:37:47.619 --> 00:37:50.760
and maximum stability. Who is that typically

00:37:50.760 --> 00:37:53.079
recommended for? Total wrist fusion is often

00:37:53.079 --> 00:37:56.219
recommended for individuals in stage 3 who require

00:37:56.219 --> 00:37:58.639
maximal strength and stability over flexibility,

00:37:59.219 --> 00:38:01.360
perhaps those performing heavy manual labor.

00:38:01.630 --> 00:38:03.929
It's important to note, though, that while you

00:38:03.929 --> 00:38:07.190
lose wrist motion, you retain full forearm rotation,

00:38:07.250 --> 00:38:09.909
turning your palm up and down, pronation and

00:38:09.909 --> 00:38:12.630
supination, which is crucial for many daily tasks.

00:38:12.869 --> 00:38:14.530
What about just taking the lunate out? Is that

00:38:14.530 --> 00:38:17.309
ever done? A more traditional and perhaps less

00:38:17.309 --> 00:38:19.409
commonly performed procedure now for advanced

00:38:19.409 --> 00:38:22.860
stages is simple lunate excision. just removing

00:38:22.860 --> 00:38:25.960
the lunate bone. However, this method on its

00:38:25.960 --> 00:38:28.400
own is associated with a high risk of subsequent

00:38:28.400 --> 00:38:31.199
carpal collapse and instability because of the

00:38:31.199 --> 00:38:33.219
void it leaves behind. Right, things could just

00:38:33.219 --> 00:38:36.599
fall into the gap. Exactly. So sometimes it's

00:38:36.599 --> 00:38:39.300
combined with interposition techniques. For example,

00:38:39.559 --> 00:38:42.340
using a harvested tendon, like the pulmaris longus

00:38:42.340 --> 00:38:45.000
tendon from the forearm, fashioned into a ball

00:38:45.000 --> 00:38:47.820
to try and fill the space and maintain some carpal

00:38:47.820 --> 00:38:50.019
height and stability. That's known as tendon

00:38:50.019 --> 00:38:52.960
ball arthroplasty. It aims to mitigate some of

00:38:52.960 --> 00:38:54.599
the complications of just removing the bone.

00:38:55.039 --> 00:38:57.199
Are there options for replacing the joint like

00:38:57.199 --> 00:39:00.380
a prosthetic wrist? Yes. Total wrist arthroplasty

00:39:00.380 --> 00:39:02.780
using an artificial joint replacement is also

00:39:02.780 --> 00:39:05.420
an option for stage 4 disease, similar in concept

00:39:05.420 --> 00:39:08.239
to hip or knee replacements. It aims to preserve

00:39:08.239 --> 00:39:11.000
more motion than a total fusion while still relieving

00:39:11.000 --> 00:39:13.599
pain. But how reliable are they? Well, the sources

00:39:13.599 --> 00:39:16.199
indicate that the long -term results and durability

00:39:16.199 --> 00:39:19.559
of total wrist arthroplasty are not as well established

00:39:19.559 --> 00:39:22.000
or predictable. compared to total wrist fusion,

00:39:22.699 --> 00:39:24.539
particularly if the wrist is subjected to heavy

00:39:24.539 --> 00:39:27.880
loads. It's typically considered more for patients

00:39:27.880 --> 00:39:30.280
with lower functional demands or perhaps those

00:39:30.280 --> 00:39:32.219
who absolutely cannot tolerate the stiffness

00:39:32.219 --> 00:39:34.800
of the fusion, maybe due to bilateral issues.

00:39:35.099 --> 00:39:37.539
Any other techniques worth mentioning? The sources

00:39:37.539 --> 00:39:39.619
also briefly mention a couple of other techniques

00:39:39.619 --> 00:39:43.699
used in specific circumstances. Temporary scaphotripeziotropazoidal

00:39:43.800 --> 00:39:46.900
STT pinning can sometimes be used in adolescents

00:39:46.900 --> 00:39:50.340
with progressive pain to stabilize the scaphoid

00:39:50.340 --> 00:39:52.619
and unload the lunate while they're still growing.

00:39:53.480 --> 00:39:56.000
And a capitate -shortening osteotomy, sometimes

00:39:56.000 --> 00:39:57.920
combined with a capital hamit fusion known as

00:39:57.920 --> 00:40:00.760
the Omquist procedure, is another approach designed

00:40:00.760 --> 00:40:03.219
to decompress the lunate, particularly in cases

00:40:03.219 --> 00:40:05.579
with neutral or positive ulnar variants. Does

00:40:05.579 --> 00:40:08.320
shortening the capitate help the lunate? It can.

00:40:08.780 --> 00:40:11.539
The sources give interesting data here too. Capitate

00:40:11.539 --> 00:40:14.420
shortening combined with Capito -Hammett fusion

00:40:14.420 --> 00:40:17.300
can decrease radiolunate stress significantly

00:40:17.300 --> 00:40:20.800
by about 66 percent. However, it does transfer

00:40:20.800 --> 00:40:22.760
load elsewhere, increasing the stress on the

00:40:22.760 --> 00:40:25.940
radioscapoid joint by around 26 percent, which

00:40:25.940 --> 00:40:27.860
could potentially increase the risk of future

00:40:27.860 --> 00:40:30.199
osteoarthritis developing there. So there are

00:40:30.199 --> 00:40:32.769
always trade -offs. It's clear there are so many

00:40:32.769 --> 00:40:35.590
surgical paths, each with its own specific goals,

00:40:35.869 --> 00:40:38.550
indications based on stage and anatomy and very

00:40:38.550 --> 00:40:40.570
distinct trade -offs in terms of pain relief

00:40:40.570 --> 00:40:43.409
versus motion versus stability. Choosing the

00:40:43.409 --> 00:40:45.630
right approach must be a really complex decision

00:40:45.630 --> 00:40:47.829
for both the patient and the surgical team. It

00:40:47.829 --> 00:40:50.469
absolutely is. It requires very careful consideration

00:40:50.469 --> 00:40:53.190
of the disease state, the patient's individual

00:40:53.190 --> 00:40:56.210
functional needs and expectations, and a thorough

00:40:56.210 --> 00:40:58.630
discussion of the potential risks, benefits,

00:40:58.750 --> 00:41:00.829
and long -term consequences of each procedure.

00:41:00.989 --> 00:41:03.530
After any of these treatments, whether it's non

00:41:03.530 --> 00:41:05.469
-operative immobilization or one of the surgical

00:41:05.469 --> 00:41:07.829
procedures, what does the recovery process typically

00:41:07.829 --> 00:41:10.389
involve? It can't be quick. No, recovery is a

00:41:10.389 --> 00:41:13.289
critical and often lengthy phase that definitely

00:41:13.289 --> 00:41:15.750
demands patients and dedicated rehabilitation.

00:41:16.769 --> 00:41:19.269
Following a period of immobilization in a cast

00:41:19.269 --> 00:41:22.190
or splint, which as we said can range from several

00:41:22.190 --> 00:41:24.750
weeks to several months, depending on the procedure

00:41:24.750 --> 00:41:28.190
or the non -operative plan, patients then transition

00:41:28.190 --> 00:41:31.150
into rehabilitation. And that involves therapy?

00:41:31.349 --> 00:41:33.969
Yes. The core of recovery involves working closely

00:41:33.969 --> 00:41:37.090
with a specialized physical therapist, or occupational

00:41:37.090 --> 00:41:39.829
therapist, often referred to as a hand therapist.

00:41:40.449 --> 00:41:42.889
Their role is absolutely crucial in guiding the

00:41:42.889 --> 00:41:44.849
patient through a structured program designed

00:41:44.849 --> 00:41:47.780
to regain function. What does that structured

00:41:47.780 --> 00:41:50.000
rehab program typically look like? What are the

00:41:50.000 --> 00:41:52.679
stages? It's typically staged, yes. The initial

00:41:52.679 --> 00:41:55.179
focus is usually on managing any post -treatment

00:41:55.179 --> 00:41:57.340
pain and swelling, and then restore a basic,

00:41:57.500 --> 00:41:59.860
gentle range of motion to prevent stiffness setting

00:41:59.860 --> 00:42:03.059
in. As healing progresses, the program advances

00:42:03.059 --> 00:42:05.539
to include strengthening exercises to rebuild

00:42:05.539 --> 00:42:08.119
muscle power in the forearm and hand, including

00:42:08.119 --> 00:42:10.599
grip strength, which is often significantly weakened

00:42:10.599 --> 00:42:12.900
by the disease and the period of inactivity.

00:42:13.070 --> 00:42:15.570
Finally, it moves towards improving fine motor

00:42:15.570 --> 00:42:18.449
control and dexterity through specific exercises,

00:42:19.070 --> 00:42:21.110
helping the patient regain the ability to perform

00:42:21.110 --> 00:42:24.190
more complex tasks needed for daily living or

00:42:24.190 --> 00:42:26.789
work. Hand therapists also provide essential

00:42:26.789 --> 00:42:29.349
guidance on activity modification and ergonomic

00:42:29.349 --> 00:42:31.929
strategies to help protect the wrist from excessive

00:42:31.929 --> 00:42:34.489
load or stress in the future, trying to prevent

00:42:34.489 --> 00:42:37.489
recurrence or further issues. How important is

00:42:37.489 --> 00:42:40.400
that rehab? It's vital for patients to understand

00:42:40.400 --> 00:42:43.119
that while rehabilitation is essential for maximizing

00:42:43.119 --> 00:42:45.659
their functional outcome, regaining as much strength

00:42:45.659 --> 00:42:47.659
and motion as possible within the limitations

00:42:47.659 --> 00:42:50.000
imposed by the disease or the chosen treatment,

00:42:50.820 --> 00:42:52.820
it doesn't cure the underlying disease process

00:42:52.820 --> 00:42:55.760
itself. The goal of rehab is really to help the

00:42:55.760 --> 00:42:58.000
patient adapt to their post -treatment risk mechanics

00:42:58.000 --> 00:43:00.659
and maximize their ability to use their hand

00:43:00.659 --> 00:43:03.550
as effectively as possible. Given the unpredictable

00:43:03.550 --> 00:43:05.849
nature of Keenbox that we've discussed and the

00:43:05.849 --> 00:43:08.329
range of interventions, what does the long -term

00:43:08.329 --> 00:43:10.670
prognosis look like for someone diagnosed with

00:43:10.670 --> 00:43:12.789
this condition? What does the future hold? Well,

00:43:13.090 --> 00:43:15.230
the sources highlight a somewhat sobering reality.

00:43:15.829 --> 00:43:18.530
Keenbox disease, if left completely untreated,

00:43:18.929 --> 00:43:21.590
is considered invariably progressive. Without

00:43:21.590 --> 00:43:24.250
intervention, the loss of blood supply inevitably

00:43:24.250 --> 00:43:26.929
leads to bone death, fragmentation, collapse,

00:43:27.510 --> 00:43:29.949
and ultimately significant degenerative arthritis

00:43:29.949 --> 00:43:32.510
throughout the wrist. This progression can often

00:43:32.510 --> 00:43:34.929
lead to severe joint destruction and considerable

00:43:34.929 --> 00:43:37.610
loss of function within, say, three to five years

00:43:37.610 --> 00:43:40.409
of symptom onset in many cases. That sounds quite

00:43:40.409 --> 00:43:42.690
serious if it's just left. It is. It's ignored.

00:43:43.130 --> 00:43:45.690
However, and this is the unpredictable aspect

00:43:45.690 --> 00:43:48.530
we keep coming back to, the rate and extent of

00:43:48.530 --> 00:43:50.550
that progression can vary significantly between

00:43:50.550 --> 00:43:53.409
individuals. As the sources note, not every case

00:43:53.409 --> 00:43:55.630
marches predictably through all four stages from

00:43:55.630 --> 00:43:57.889
I to biv. So it's not always a straight line.

00:43:58.170 --> 00:44:01.010
Not always. Some individuals, particularly those

00:44:01.010 --> 00:44:03.670
diagnosed in earlier stages or perhaps with less

00:44:03.670 --> 00:44:06.329
severe underlying risk factors, might experience

00:44:06.329 --> 00:44:08.789
much slower progression or have relatively mild

00:44:08.789 --> 00:44:11.409
symptoms for a longer period, despite radiographic

00:44:11.409 --> 00:44:14.639
changes being visible. And in very rare instances,

00:44:14.699 --> 00:44:17.280
spontaneous improvement or even cessation of

00:44:17.280 --> 00:44:19.159
progression has been reported, though this is

00:44:19.159 --> 00:44:21.500
definitely uncommon, especially in adults. You

00:44:21.500 --> 00:44:24.079
can't rely on that happening. So it's progressive

00:44:24.079 --> 00:44:27.000
generally, but the path isn't set in stone for

00:44:27.000 --> 00:44:30.239
everyone. What factors do influence the prognosis?

00:44:30.320 --> 00:44:33.380
What makes it more likely to be worse? Several

00:44:33.380 --> 00:44:35.400
factors are associated with a less favorable

00:44:35.400 --> 00:44:37.980
prognosis and a higher likelihood of faster progression

00:44:37.980 --> 00:44:40.960
or worse outcomes. The functional stage we discussed

00:44:40.960 --> 00:44:43.949
is key. the greater the extent of viable bones

00:44:43.949 --> 00:44:46.610
seen on functional MRI. Generally, the better

00:44:46.610 --> 00:44:49.130
the potential for success with revascularization

00:44:49.130 --> 00:44:51.389
and perhaps a more favorable outlook overall.

00:44:51.590 --> 00:44:54.130
Makes sense. The degree of negative ulnar variance

00:44:54.130 --> 00:44:56.949
is also strongly correlated. The more ulna minus

00:44:56.949 --> 00:44:59.309
the patient has, the more severe the biomechanical

00:44:59.309 --> 00:45:01.630
stress and the more likely the disease is to

00:45:01.630 --> 00:45:04.869
progress to advanced stages. Age at diagnosis

00:45:04.869 --> 00:45:07.900
is also a factor. Patients diagnosed at an older

00:45:07.900 --> 00:45:10.219
age are more likely to already have more advanced

00:45:10.219 --> 00:45:13.079
stage disease when they present, and may experience

00:45:13.079 --> 00:45:15.980
more rapid progression subsequently. And treatment,

00:45:16.059 --> 00:45:18.559
does that change the prognosis? While treatment

00:45:18.559 --> 00:45:20.880
can significantly improve pain and function,

00:45:21.460 --> 00:45:23.780
the sources acknowledge that outcomes can still

00:45:23.780 --> 00:45:26.719
vary, often categorized in studies as excellent,

00:45:27.099 --> 00:45:30.159
good, fair, or poor. Treatment aims to manage

00:45:30.159 --> 00:45:33.000
symptoms, improve function, and potentially slow

00:45:33.000 --> 00:45:35.400
down the progression, even if the imaging findings

00:45:35.400 --> 00:45:38.119
in later stages still show considerable structural

00:45:38.119 --> 00:45:40.619
damage has occurred. Are there long -term problems

00:45:40.619 --> 00:45:44.079
even after treatment? Unfortunately, yes. Even

00:45:44.079 --> 00:45:46.500
after successful initial treatment, there are

00:45:46.500 --> 00:45:48.659
potential long -term complications to be aware

00:45:48.659 --> 00:45:51.599
of. These can include persistent or recurrent

00:45:51.599 --> 00:45:54.340
pain, stiffness, and residual limitations in

00:45:54.340 --> 00:45:57.699
motion or strength. Specific complications related

00:45:57.699 --> 00:46:00.139
to the altered wrist mechanics or the surgical

00:46:00.139 --> 00:46:02.559
interventions themselves can include things like

00:46:02.559 --> 00:46:05.079
scapholunate dissociation, that's instability

00:46:05.079 --> 00:46:07.619
developing between the scaphoid and the lunates

00:46:07.619 --> 00:46:11.400
remaining portions or its neighbors. Also, secondary

00:46:11.400 --> 00:46:14.300
degenerative arthrosis, or arthritis, developing

00:46:14.300 --> 00:46:16.619
over time in joints that now take on increased

00:46:16.619 --> 00:46:19.199
load because of the surgery, like the radioscapoid

00:46:19.199 --> 00:46:21.000
joint after a capitate shortening or certain

00:46:21.000 --> 00:46:23.860
partial fusions. And malignment of other carpal

00:46:23.860 --> 00:46:26.920
bones, like the trichotrum, can occur. That increased

00:46:26.920 --> 00:46:29.300
stress on the radial side of the wrist post -treatment

00:46:29.300 --> 00:46:31.900
is a persistent risk factor for developing future

00:46:31.900 --> 00:46:34.809
osteoarthritis. And given the progressive nature

00:46:34.809 --> 00:46:37.409
and these potential complications, is it common

00:46:37.409 --> 00:46:39.690
for someone with Kinbox to require more than

00:46:39.690 --> 00:46:42.530
one procedure over their lifetime? Yes, that

00:46:42.530 --> 00:46:45.269
is a distinct possibility, particularly perhaps

00:46:45.269 --> 00:46:47.989
in younger patients or those with more aggressive

00:46:47.989 --> 00:46:51.650
disease patterns or who develop significant complications.

00:46:51.980 --> 00:46:54.500
The sources acknowledge that Keenbox disease

00:46:54.500 --> 00:46:57.019
can really be a lifelong condition requiring

00:46:57.019 --> 00:47:00.420
ongoing management, and some patients may unfortunately

00:47:00.420 --> 00:47:03.320
need multiple surgical procedures over time as

00:47:03.320 --> 00:47:05.980
the disease progresses or complications arise

00:47:05.980 --> 00:47:08.460
from previous interventions. It truly sounds

00:47:08.460 --> 00:47:10.980
like a condition that requires a comprehensive,

00:47:11.420 --> 00:47:14.559
long -term approach involving very careful decision

00:47:14.559 --> 00:47:17.300
making every step of the way and relying heavily

00:47:17.300 --> 00:47:19.659
on an experienced healthcare team. Absolutely.

00:47:20.199 --> 00:47:22.480
The sources really emphasize the value of an

00:47:22.480 --> 00:47:25.079
interprofessional team approach involving hand

00:47:25.079 --> 00:47:27.860
surgeons, radiologists, and specialist hand therapists

00:47:27.860 --> 00:47:30.920
all working together for optimal diagnosis, planning,

00:47:31.059 --> 00:47:32.980
and management throughout the patient's journey

00:47:32.980 --> 00:47:35.360
with this condition. So we've taken a deep dive

00:47:35.360 --> 00:47:38.000
today into Keenbok's disease, exploring that

00:47:38.000 --> 00:47:40.739
delicate lunete bone, the complex interplay of

00:47:40.739 --> 00:47:43.320
factors from subtle anatomical variations to

00:47:43.320 --> 00:47:45.579
vascular patterns and repetitive stress that

00:47:45.579 --> 00:47:48.159
contribute to its mysterious failure. We have.

00:47:48.559 --> 00:47:50.719
And we've seen how challenging diagnosis can

00:47:50.719 --> 00:47:53.079
be, often mimicking simpler issues initially,

00:47:53.079 --> 00:47:57.980
and how advanced imaging like MRI and CT is absolutely

00:47:57.980 --> 00:48:00.639
essential to truly see what's happening inside

00:48:00.639 --> 00:48:03.570
the bone. and to stage the disease accurately

00:48:03.570 --> 00:48:06.389
using classifications like Lickman. And we've

00:48:06.389 --> 00:48:08.230
mapped out the wide spectrum of treatment options,

00:48:08.389 --> 00:48:10.809
haven't we? Ranging from fairly limited non -operative

00:48:10.809 --> 00:48:13.110
measures to quite complex surgical procedures

00:48:13.110 --> 00:48:15.989
aimed at leveling bones, revascularizing the

00:48:15.989 --> 00:48:18.530
lunet in early stages, or performing salvage

00:48:18.530 --> 00:48:21.650
procedures like partial or total fusions or proximal

00:48:21.650 --> 00:48:24.469
rocarpectomy in later stages, each, as we've

00:48:24.469 --> 00:48:26.409
stressed, with its own benefits and inherent

00:48:26.409 --> 00:48:28.469
trade -offs. And we've discussed the long view

00:48:28.469 --> 00:48:30.769
that while it's invariably progressive if left

00:48:30.769 --> 00:48:33.650
untreated, the disease course itself is unpredictable.

00:48:33.980 --> 00:48:36.760
And even with timely interventions and dedicated

00:48:36.760 --> 00:48:39.860
rehabilitation, it can lead to long -term complications

00:48:39.860 --> 00:48:42.119
and potentially require multiple procedures,

00:48:42.780 --> 00:48:44.940
making it a condition requiring ongoing care

00:48:44.940 --> 00:48:47.239
and adaptation from the patient. If you found

00:48:47.239 --> 00:48:49.500
this discussion helpful, perhaps consider sharing

00:48:49.500 --> 00:48:51.519
it with colleagues who might also benefit. What

00:48:51.519 --> 00:48:53.639
stands out to you most about the complexity of

00:48:53.639 --> 00:48:56.360
Keenbox disease? Especially considering those

00:48:56.360 --> 00:48:58.639
really difficult trade -offs, patients and doctors

00:48:58.639 --> 00:49:01.320
must weigh balancing pain relief against preserving

00:49:01.320 --> 00:49:04.139
precious wrist motion, or accepting the risks

00:49:04.139 --> 00:49:06.679
and limitations of potentially multiple interventions

00:49:06.679 --> 00:49:09.639
over a lifetime. It's a condition that really

00:49:09.639 --> 00:49:11.539
highlights the intricate mechanics of the human

00:49:11.539 --> 00:49:14.420
body and the profound challenges of intervening

00:49:14.420 --> 00:49:16.380
when a fundamental supply line to a critical

00:49:16.380 --> 00:49:18.400
structure fails, isn't it? It really does. It

00:49:18.400 --> 00:49:20.480
underscores the importance of early diagnosis,

00:49:21.039 --> 00:49:23.059
tailored treatment, and realistic expectations.

00:49:23.679 --> 00:49:25.320
A fascinating and challenging condition.