OK, let's start with a statistic that really
drives home the stakes here. Scaphoid fractures.
This small bone in your wrist, it's the most
commonly fractured carpal bone, making up something
like 60 % of all wrist bone breaks. That's right.
A huge proportion. And you might think, all right,
a simple wrist break after a fall. But here's
the critical part, depending on where it breaks,
how it's treated. Well, a significant percentage,
potentially 15 to 50 percent overall, maybe even
hitting 100 percent in those tricky proximal
pole fractures if not handled correctly, can
lead to a vascular necrosis. Essentially bone
death. Exactly, bone death. That seemingly simple
fall can just unravel into chronic pain, loss
of function, maybe even a career -threatening
problem for someone relying on their hands. And
so much of that risk comes down to the scaphoids'
peculiar structure, that sort of twisted peanut
shape we talk about. Right. complex, almost awkward
blood supply. Welcome to the Deep Dive. This
is where we take complex information research
papers, clinical guidelines, expert knowledge,
and really extract the vital insights, giving
you the shortcut to being truly well -informed.
Today we are taking a profound look into scaphoid
fractures, navigating the orthopedic knowledge
and clinical practices necessary to understand
and manage this, well, really challenging injury.
And guiding us through this deep dive is Professor
Mo Imam, a distinguished expert in musculoskeletal
trauma and hand surgery. Professor Imam, it's
a real privilege to have you join us. Thank you.
It's a crucial topic and I'm glad to explore
it. The scaphoid is, well, it's a small bone.
that presents some very large clinical problems
you've not understood properly. Absolutely. So
to kick things off and maybe give you a roadmap
of where we're heading, let's hit you with three
quick high -impact questions. OK. First, just
stepping back, what exactly is a scaphoid fracture?
And fundamentally, why does it pose such unique
problems compared to, say, a break in the radius
or ulna? Well, what's critically important here
is the scaphoid's unique anatomy and its vascularization.
You see, it's the critical mechanical link between
the two rows of wrist bones, absolutely essential
for smooth motion. But unlike most bones that
have multiple points of entry for blood vessels,
the scaphoid gets the majority of its blood supply
through quite a limited area, often distal to
where the fracture occurs. Which means the blood
has to flow retrograde backwards towards that
vital proximal pole. This sets it apart entirely
from breaks in the long bones of the forearm.
That retrograde flow sounds like a, well, a built
-in vulnerability, doesn't it? It absolutely
is. Second question, then. Beyond just the initial
break healing, what are the most significant,
potentially devastating complications that professionals,
especially those who use their hands intensely,
must absolutely be aware of? Yes. This really
raises the specter of long -term disability.
The primary complications are non -union, meaning
the fracture simply fails to heal, endovascular
necrosis, or AVN, where the bone tissue actually
dies due to that lack of blood supply. Okay.
Either of these can lead to malunion, where it
heals crookedly, progressive carpal collapse,
and ultimately debilitating osteoarthritis of
the wrist. These aren't minor setbacks. They
really can be career -ending issues. Non -union
and AVN, those are the big risks. Okay. Finally,
if you had to boil it all down, Is there one
single most critical factor in achieving a good
outcome for a scaphoid fracture? That's a key
question. If we distill all the evidence and,
you know, clinical experience, the single most
critical factor is probably an early accurate
diagnosis. Right. Followed immediately by appropriate
individualized management. And that management
has to be based on a thorough assessment of the
fracture characteristics. Hesitation or misdiagnosis
significantly increases the risk of those complications
we just mentioned. Early, accurate diagnosis
and appropriate management. Sounds like a bit
of a race against the clock and the anatomy itself.
In many ways, yes. So let's start by understanding
the star of our show, the scaphoid bone itself.
We often hear it called boat -shaped from its
Greek origin, but you prefer twisted peanut.
Why is that shape significant? Indeed. Oskifodium
does translate to boat shapes. And I suppose
if you look at it from one angle, maybe it vaguely
resembles a small boat. But the twisted peanut
analogy, while less scientific, perhaps gives
you a better sense of its complex 3D geometry
and its angulation. It's not a simple straight
bone. OK. This shape is crucial because it has
two main articulating surfaces, fitting neatly
into the proximal and distal carpal rows. And
the vast majority of its surface, over 75%, is
covered in smooth articular cartilage, which
is essential for wrist movement. Right, for the
gliding. Exactly. But this also means there's
very little raw bone surface available for soft
tissues, ligaments, or critically, blood vessels
to attach and actually enter the bone. The main
area where blood vessels can get in is a small,
non -articular area known as the dorsal ridge.
So the very structure designed for smooth movement
actually limits where its lifeblood can get in.
Precisely. It's a trade -off. Let's dive deeper
into that critical, tricky blood supply, maybe
drawing on that foundational research. What did
the classic Gelberman and Menon study from 1980
using those latex injections really reveal about
the scaphoid's vascularity? Yes, that study published
in the Journal of Hand Surgery was absolutely
seminal. It meticulously mapped the scaphoid's
blood supply. They identified two primary sources
or vascular leashes, as they call them. OK. The
dominant supply comes from the dorsal ridge artery.
Now, this is a branch of the radial artery, and
it's responsible for a significant majority,
perhaps 70 to 80 percent, of the scaphoid's total
blood flow. It enters the bone through that non
-articular dorsal ridge we just discussed. The
small entry point on the back. And this is where
the retrograde flow comes in, correct? Precisely.
The blood vessels entering the dorsal ridge predominantly
supply the distal and middle parts of the scaphoid
first. OK. So to reach the crucial proximal pole
that's the part closest to the forearm bones,
the blood has to flow backwards or retrogradedly
up the length of the bone. It's quite counterintuitive
compared to how blood typically flows into most
bones. So blood comes in effectively at one end
and has to push upstream to reach the other end.
That seems inherently risky. Exactly. Now there
is a secondary minor supply from the palmar side
via branches of the palmar and superficial palmar
radial artery. These vessels enter near the distal
tubercle and supply roughly the distal 20 to
30 percent of the scaphoid. OK, so combining
these, you've got the main supply coming in dorsally,
flowing retrograde -ly, and a smaller supply
coming in palmerly just to the distal bit. That
specific setup creates a significant vulnerability.
The area reliant on that retrograde flow, particularly
the proximal pole, is effectively in a watershed
zone. A watershed zone, right. So if a fracture
occurs between where those dominant dorsal vessels
enter and the proximal pole itself, that proximal
fragment can be entirely cut off from his blood
supply. Completely isolated. Yes. And the small
palmar supply is usually insufficient to sustain
it. This is the fundamental anatomical reason
why proximal pole fractures are at such a high
risk of vascular necrosis. The blood simply can't
get there. That anatomical detail is just incredibly
important for understanding the prognosis, isn't
it? Absolutely fundamental. No. Turning to how
and where these fractures typically happen, what
does the epidemiology tell us? Who gets these,
and why? Well, epidemiologically, scaphoid fractures
are, as you mentioned right at the start, the
most common carpal fracture. They make up about
60 % of all carpal breaks and maybe 15 % of acute
wrist injuries generally. OK. The highest incidence
is in young, active men. particularly in their
third decade of life. The male to female ratio
is often cited around 2 .1. So it's often associated
with activities then, sports, falls. Absolutely.
The overwhelming etiology that causes a fall
onto an outstretched hand, the classic foosh
injury. This mechanism typically involves the
wrist being forced into hyperdorsiflexion, often
with an axial load pushing down some pronation
and frequently concurrent ulnar deviation, the
wrist bending towards the little finger side.
That's the classic scenario, isn't it? Tripping,
falling off a bike. Exactly. Sports, falls from
height, or simply tripping on the pavement. It's
worth noting, too, that this foosh with ulnar
deviation can also simultaneously injure ligaments
around the wrist. Sometimes it leads to what
we call a dis -e deformity dorsal intercalated
segmental instability. OK, what does that mean?
It essentially means the middle row of carpal
bones tilts backwards abnormally, which adds
another layer of complexity to the injury. Right,
so it's not just the scaphoid break, that makes
sense. And where in this twisted peanut does
it most commonly break? You mentioned the proximal
pole is riskiest, but is it the most frequent?
No, interestingly, while the proximal pole is
the riskiest spot for complications, it's not
the most frequent location for the fracture itself.
The most common fracture location is the waist,
the narrowest part of the bone. That counts for
about 65 % of scaphoid fractures. The majority,
then? Yes. Fractures in the proximal third are
next most common at around 25 % and fractures
of the distal third or the little tubercle at
the end are the least common, making up perhaps
10%. There used to be belief that distal fractures
were more common in children. But more recent
large series suggest that waste fractures are
now actually the predominant site across most
age groups. So the waste is the frequent flyer,
but the proximal third is the high -risk passenger.
That's a good way to put it, yes. This brings
us neatly to classification systems. Why is it
so vital to classify a scaphoid fracture beyond
just saying it's broken? Oh, classification is
absolutely paramount because it's really the
foundation for clinical decision -making. It
helps us assess the fracture stability. understand
its likely prognosis, and ultimately dictates
the most appropriate treatment strategy. Whether
it's casting or surgery. Precisely. Whether that's
casting or surgery and indeed what type of surgery
might be needed. A proper classification guides
us towards maximizing the chance of union healing
and minimizing those complications we talked
about. The Herbert classification is widely used,
isn't it? It seems to be based specifically on
stability and also the timing. Whether it's acute
or older, could you walk us through the main
types? Yes, the Herbert classification is very
clinically relevant because it categorizes fractures
based on factors that directly impact treatment
and outcome. It divides fractures into four main
types A, B, C, and D. Okay. Type A. represents
stable acute fractures. These are generally lower
risk and include A1, which is a fracture of that
distal tubercle. The little end bit, yes. And
A2, which is an incomplete waste fracture, meaning
the crack doesn't go all the way across the bone.
Right, so those are relatively safe bets for
healing. Generally, yes, with appropriate immobilization.
Then you have type B, which represents unstable
acute fractures. Now these are the ones that
often require surgery due to their inherent risk
of not healing well or displacing. Okay, what's
in type B? This category includes B1, a distal
oblique fracture, which is prone to shear forces
and slipping. B2, a complete waist fracture,
which is considered unstable because it breaks
the main structural support across the middle.
B3, a proximal pull fracture, which we know is
unstable due to that high AVN risk and the anatomical
difficulty. The blood supply issue again? Exactly.
And B4, which is a very significant injury, indeed
a transcephoid -paralinate fracture dislocation.
That involves major disruption of the ligaments
around the lunate bone as well as the scaphoid
brick itself. Wow. Okay. So type A is relatively
stable. Type B is unstable and problematic. What
about C and D? Type C is designated for delayed
union. This is when the fracture hasn't healed
within the expected time frame, say after several
months of casting. But there's still thought
to be some biological potential for it to heal,
perhaps with further immobilization or maybe
some intervention. So slow healing, but not given
up yet. Precisely. And then type D is for established
non -union. This means the bone has failed to
heal, the healing process is effectively stopped,
and it requires intervention to achieve union.
And Herbert breaks down non -union further. Yes,
Herbert further subdivides non -union. which
is useful prognosically. D1 is a fibrous union
where there's maybe some soft tissue connection,
but no solid bone bridging the gap. D2 is a pseudothrosis,
which literally means a false joint with instability
and often early deformity starting to develop.
Like it's moving where it shouldn't. Exactly.
D3 is a sclerotic pseudothrosis. which is a more
established false joint where the bone edges
have become hardened and dense, often with significant
deformity like that humpback shape. And finally,
D4 indicates avian avascular necrosis associated
with the non -union, often presenting as a fragmented
or collapsed proximal pole. That progression
to D4 sounds like the real end stage of that
avian risk we discussed right at the start. It
often is, yes. It represents significant biological
failure. Are there other classification systems
that clinicians use alongside Herbert? Yes, there
are others that focus on slightly different aspects,
which can be complementary. The Mayo classification
is a simpler system based purely on the anatomical
location. Type 1 is a distal tubercle. Type 2,
the distal articular surface. 3, the distal third.
4, the middle third or waist. And type V, the
proximal third. So just location. Just location.
And the Roast classification describes the fracture
line pattern or its orientation. Horizontal oblique.
transverse straight across, and vertical oblique.
Why does the pattern matter? Well, a vertical
oblique fracture pattern, for instance, is a
known risk factor for instability and nonunion.
Because the fracture line runs more vertically,
it's much more prone to shearing forces when
the wrist is loaded, making it harder to hold
reduced and less likely to heal in a cast. I
see. So Herbert gives you the stability and chronicity
picture, Mayo gives location, and Russ adds the
fracture pattern detail. And combining these
helps make the treatment decision. Exactly. The
classification, drawn on these different aspects,
directly informs the management pathway. Stable,
undisplaced fractures, typically Herbert type
A or maybe non -displaced type B2 or B3, depending
on surgeon preference and careful imaging, and
often majoroos types without displacement or
vertical patterns are usually candidates for
non -operative management with casting. Whereas
unstable, acute fractures, Herbert type B, vertical
oblique patterns, any proximal pole fracture,
really. Those with significant displacement or
angulation seen on imaging almost always require
operative intervention due to the high likelihood
of non - union or malunion if you simply put
them in a cast. Right, the classification is
absolutely the roadmap to treatment. Now, let's
talk about actually spotting this injury in the
first place. Given there's often no dramatic
deformity, how do clinicians typically diagnose
a scaphoid fracture? What are the key clinical
signs to look for? Clinically, the cardinal sign,
the one everyone learns, is tenderness in the
anatomical snuff box. That little hollow on the
back of your wrist? Exactly, on the thumb side,
formed when you extend your thumb out. Pressing
firmly in that area after a foosh injury is highly
suggestive. Its sensitivity for detecting a scaphoid
fracture is reported to be high, maybe up to
90%. That's quite high. It is, but it's crucial
to remember that other injuries, like ligament
sprains or fractures of the radial styloid, can
also cause snuff box tenderness. So it's sensitive,
but not perfectly specific. It doesn't absolutely
confirm a scaphoid fracture on its own. Okay,
so it's a strong clue, but not proof. What else?
Other signs include general swelling around the
radial side of the wrist, often some reduced
range of motion, particularly wrist extension
and radial deviation. Pain with forceful resisted
pronation of the forearm can sometimes elicit
pain. And there's a positive scaphoid compression
test, where you push axially along the line of
the thumb metacarpal towards the wrist, and that
reproduces their specific pain. Right. But the
key challenge, as you said, is that unlike, say,
a broken forearm bone, there's usually no obvious
deformity. The wrist might look a bit swollen,
maybe bruised, but often not dramatically out
of shape. This makes it really easy to mistake
for a simple wrist sprain, especially in the
heat of the moment, like on a sports field or
in a busy A &E. So the take -home is, after a
fall onto an outstretched hand, if there's snuff
box tenderness, you really should have a high
clinical suspicion. What's the crucial next step,
then, in terms of imaging? The standard initial
imaging is plain x -rays, but... And this is
a really important point. You need the right
views to maximize the chance of actually seeing
the fracture, especially if it's subtle or undisplaced.
But not just the standard two views. No, definitely
not. Relying on just standard PA, postural interior,
and lateral views is often insufficient. The
sources consistently recommend a minimum of four
or ideally five specific views. This includes
the standard PA and a true lateral. OK. But crucially,
also, PA view is taken in 45 degrees of oblique
pronation and 45 degrees of oblique supination.
And the PA view taken with the wrist in maximum
ulnar deviation bending towards the little finger.
Why the honored deviation view? That specific
view helps to elongate the scaphoid, straightening
out its natural curve on the x -ray image, which
makes fractures across the waist much more visible
than they might be in the standard neutral PA
view. Right, it sort of uncoils it visually.
Exactly. And beyond just looking for the fracture
line itself, on the x -rays you also look for
other radiographic signs, things like sclerosis,
which is increased bone density along the fracture
line, suggesting poor healing or maybe even early
bone death. or looking for that humpback deformity
on the lateral view, which is an increased intraskeifoid
angle. How much of an angle is abnormal? Generally,
an angle over 35 degrees suggests some deformity,
and an angle greater than 45 degrees is strongly
associated with poor outcomes and the likely
development of that dizzy instability pattern
we mentioned earlier. Okay. Now... There's the
historical approach, the two -week delay, where
initial x -rays are negative but your suspicion
is high, you cast the wrist and repeat the x
-rays two weeks later. What was the thinking
behind this, and is it still the recommended
practice today? This was a very common practice
for many years based on the idea that bone resorption,
a natural process occurring around a fracture
line in the early healing phase, might make a
previously invisible, occult, non -displaced
fracture become visible on a follow -up x -ray
after a period of immobilization. The line might
become clearer. That was the theory. However,
evidence such as that quite pivotal 1981 Leslie
and Dixon study of the JBJS has really challenged
the utility of this approach. They reviewed a
large series of patients presenting with scaphoid
fractures and found that a staggering 98 % of
these fractures were actually visible on the
initial radiographic series, provided that adequate
views, those multiple views we just discussed,
were obtained. 98 % were visible initially. Yes.
Only a tiny 2 % became apparent only on the later
X -rays. And these were typically only very minor
incomplete fractures located on the concave side
of the bone. So the vast majority are there to
be seen if you look correctly the first time.
What's the implication of that finding for the
whole two -week delay strategy? Well, the implication
is pretty profound, really. Waiting two weeks
misses almost nothing that wasn't truly visible
initially and only picks up a very small number
of potentially insignificant incomplete fractures
later on. But crucially, what it does do is it
delays definitive diagnosis and potentially the
appropriate treatment for a full 14 days. During
that delay, a fracture that might have been minimally
displaced could become more displaced within
the cast, or the optimal window for early surgical
fixation, if indicated, could be missed. This
potentially increases the risk of non -union
and AVN. So paradoxically, the two -week delay
meant to avoid missing things could actually
be detrimental by delaying definitive management.
In many cases, yes, it delays certainty. So what
are the modern preferred alternatives if clinical
suspicion remains high despite negative initial
x -rays? What should be done instead of waiting
two weeks? The modern approach, which is supported
by higher quality evidence and much better technology,
is to move swiftly to advanced imaging if those
initial x -rays are negative. But your clinical
suspicion of a scaphoid fracture persists. Advanced
imaging meaning CT or MRI. Exactly. The primary
alternatives are CT or MRI. CT is widely available,
relatively quick, and generally less expensive
than MRI. It's excellent at definitively demonstrating
the presence or absence of a fracture line, even
subtle ones. And MRI. MRI is even more sensitive,
particularly for detecting truly occult fractures,
those not visible on x -ray, or even sometimes
CT, especially in the very early stages after
injury, say within the first 24 to 48 hours.
Let's break down the utility of CT and MRI a
bit further then. What specific information does
a CT scan give you that plain x -rays perhaps
can't? CT is invaluable for assessing the fracture
in fine detail. It provides high resolution images,
typically using very thin 1mm slices, which are
often reconstructed in the sagittal plane along
the scaphoid's long axis. This allows for really
accurate assessment of the precise fracture location,
the degree of angulation or deformity, and crucially
the amount of displacement between the fragments.
Displacement of greater than 1mm is widely accepted
as a key indicator of instability and a strong
predictor of poor outcome with non -operative
treatment alone. So CT is best for measuring
that gap. Yes, CT is far more effective than
x -rays, bone scans, or even MRI for precisely
measuring displacement. It's also excellent for
monitoring fracture healing progress over time,
or for assessing the characteristics of an established
non -union before planning surgery. And MRI.
You mentioned it's high sensitivity for occult
fractures. What else does it offer? MRI is really
the gold standard for diagnosing those subtle
or occult fractures that just aren't visible
on x -rays or sometimes even CT. It attacks bone
bruising, and occult fracture is essentially
a severe bone bruise very early on. It can also
show early signs of AVN. The blood supply issue
again. Exactly. AVN shows up as a characteristic
low signal intensity on both T1 and T2 weighted
images. MRI is also superior to CT for evaluating
associated soft tissue injuries like ligament
tears, particularly the scaphalunid ligament,
which can contribute significantly to overall
wrist instability. So if you have high suspicion
and a negative x -ray, an MRI gives you a definitive
answer about whether a fracture is present or
not. In most cases, yes. It often prevents the
need for prolonged unnecessary casting based
on suspicion alone. which has implications for
patient convenience and health care costs. What
about bone scans? You mentioned CT is better
for displacement. Are bone scans still part of
the diagnostic algorithm at all? Bone scans,
or scintigraphy, are highly sensitive for detecting
increased metabolic activity associated with
any bone injury, including fractures. They typically
become positive about 72 hours after the injury.
They have high specificity, around 98%, meaning
if it's negative, you likely don't have a fracture.
Yeah. But they can show increased uptake for
There are other reasons besides the scaphoid
fracture inflammation, arthritis, other injuries
leading to a 5 -15 % incidence of false positives.
OK. So while sensitive, MRI is generally considered
more sensitive and more specific for diagnosing
occult scaphoid fractures and, importantly, for
identifying early AVN. This makes MRI the preferred
advanced imaging modality in most cases where
suspicion remains high despite negative x -rays.
OK, that makes sense. So the modern approach
is high clinical suspicion plus proper initial
x -rays. And if those are negative, proceed quickly
to CT for bony detail and displacement, or ideally
MRI for occult fracture and ADN assessment, rather
than relying on the old two -week delay. That's
the current thinking, yes. Much more proactive.
This diagnostic rigor is clearly aimed at identifying
instability early on. Let's just consolidate
the criteria for what defines an unstable scaphoid
fracture, which, as you said, is absolutely key
for treatment decisions. Absolutely. Identifying
instability is paramount because it almost always
mandates surgical intervention for a predictable
outcome. Based on the literature and the classification
systems we've discussed, the key criteria for
instability include significant displacement
of the fracture fragments, generally defined
as greater than one millimeter displacement on
any radiographic view, and CT is the best tool
for assessing this accurately. One millimeter
gap or step. Got it. An intrascape white angle
greater than 35 degrees on the lateral x -ray
indicating significant regulation and the potential
for that humpback deformity. Approximal pole
fracture, location, location, location, which,
as we've hammered home, is anatomically vulnerable
and often considered unstable due to the high
blood supply risk, regardless of initial displacement
sometimes. Right. Significant comminution, meaning
the bone is breaking into multiple pieces rather
than a clean break. Shattered almost. In fact,
yes. Also, associated carpal instability, suggesting
wider ligamentous injury. Signs of this include
a scapholunar SL angle greater than 60 degrees
or a radial lunet angle greater than 15 degrees
on the lateral x -ray. Indicating the other wrist
bones aren't aligned properly. Correct. And finally,
of course, the most obvious instability pattern
is a paralunet transscapoid fracture dislocation,
the Herbert B4 type, which is a major wrist disruption.
If any of these criteria are met, the fracture
is deemed unstable. Got it. That's a clear list.
High suspicion, thorough imaging, precise classification
to identify instability. Now that we understand
the injury and how to spot it properly, what
does this all mean for getting the patient back
to full function? How are these injuries actually
managed? Well, the overarching goal of management,
regardless of the method, is firstly to achieve
bony union healing in an anatomical position.
Secondly, to relieve pain. Thirdly, to maximize
functional recovery. getting strength and movement
back. And perhaps most importantly, in the long
run, to prevent the development of those long
-term complications like non -union, malunion,
and post -traumatic arthritis. OK. And as we've
established, the approach is broadly divided
into non -operative and operative management.
And the choice is driven primarily by the fracture
classification, stable versus unstable, and also
patient factors like age, activity level, and
occupation. Let's start with non -operative management
then. When is that the appropriate route? Who
gets put in a cast? Non -operative management,
essentially casting, is typically reserved for
acute, undisplaced, stable scaphoid fractures.
So the Herbert A types. Primarily, yes. This
includes Herbert Type A fractures, those distal
tubercle or incomplete waste fractures. It can
also include certain complete waste fractures,
Herbert B2, or even some proximal bowl fractures,
Herbert B3, if they show absolutely no significant
displacement, usually less than one millimeter,
and no other signs of instability on detailed
imaging like CT. Okay. It's also, logically,
the initial approach when you have strong clinical
suspicion but your NFL X -rays are negative while
you're waiting for or arranging that definitive
CT or MRI scan. You treat it as fractured until
proven otherwise in that short interval. Makes
sense. And what does non -operative management
actually entail? Is it just a standard wrist
cast? Yes. It involves immobilization in a cast,
but specifically a scaphoid cast. The traditional
description is a well -molded cast extending
from below the elbow crease down to the hand
and, crucially, including the thumb, often up
to the interphalangeal joint. This is often called
a thumb spike a cast. Why include the thumb?
The rationale is to maximally stabilize the scaphoid
bone by preventing thumb movement. as forces
can be transmitted through the thumb metacarpal
to the scaphoid. Although, it's fair to say there
is some ongoing debate in the literature regarding
the absolute necessity of including the thumb
in the cast for all types. Some studies have
suggested that a simple short arm cast, without
the thumb included, may be sufficient for certain
stable fracture types, particularly distal ones.
But the traditional widely accepted approach
for waist and proximal fractures involves the
thumb spica component. Right. How long does someone
typically need to be in this cast? It sounds
like quite a commitment. It is, and the duration
varies significantly based on the fractural location.
This directly reflects the differing healing
potential due to that blood supply issue we keep
coming back to. So distal heals faster. Generally,
yes, distal third or tuberosity fractures having
a better blood supply might unite in as little
as six weeks. Middle third or waist fractures,
the most common type, typically require around
8 to 12 weeks of immobilization. 8 to 12 weeks.
Yes. And proximal third fractures with their
precarious retrograde blood supply. often need
10 to 12 weeks, sometimes even longer, maybe
up to 14 weeks or more in some protocols. And
even with diligent casting for that extended
period, they still have a higher rate of non
-union compared to waste fractures. Wow, that's
a significant period of immobilization, especially
for the proximal ones. What's the follow -up
protocol while they're actually in the cast?
Do you just wait until the end? No, regular follow
-up is essential. Firstly, to ensure the fracture
doesn't displace within the cast, sometimes called
secondary displacement, and secondly, to monitor
healing progress. Typically, an x -ray is taken
around two weeks after the initial casting. Primarily
confirm the fracture remains undisplaced. Check
it hasn't shifted. Exactly. Further x -rays,
sometimes CT scans later on if union is questionable,
are taken when the cast is planned to be removed
at that estimated healing time point, 6, 8, 10,
12 weeks, etc. To assess for clinical signs of
union, no tenderness, and radiographic evidence
of bone bridging the fracture line. A final check,
perhaps at 6 or 12 months post -injury, is often
recommended just to ensure the union is stable
and no leak complications are developing. If
union is confirmed at cast removal, then gradual
mobilization, physiotherapy, and return to activity
follows. And what's the success rate for casting
these stable fractures? With appropriate patient
selection meaning truly stable, undisplaced fractures,
and strict adherence to the casting protocol,
the union rate for non -operative management
is generally high, often quoted as exceeding
95%. That's encouraging for the stable ones at
least. But you mentioned operative management
is needed for the unstable or higher risk fractures.
What are the key indications for deciding on
surgery instead of a cast? Right. Operative management
is indicated when the risks of non -union, malunion,
or simply a poor functional outcome with casting
alone are considered unacceptably high. The primary
indications are those instability criteria we
defined earlier. The list we went through. Yes,
greater than one millimeter displacement, that
intrascaphoid angle over 35 degrees, significant
comminution, or associated carpal instability
like a high SL angle. Proxable pull fractures,
again due to their high AVN and non -union risk
and theoretical instability, are generally considered
strong candidates for surgery, often requiring
a specific surgical approach from the back. So
location drives surgery too. Any other reasons?
Yes. Another significant group is based on patient
factors. Certain patient groups, like high -level
athletes or heavy manual workers, even if they
have a minimally displaced or seemingly stable
fracture, might be offered surgery. Why is that?
Because surgical fixation particularly percutaneous
screw fixation, can potentially allow for quicker
union and a significantly earlier, safer return
to demanding activities compared to the prolonged
casting period, which might be unacceptable for
their career or sport. Get them back faster.
Essentially, yes. And finally, a delayed diagnosis
if a fracture is picked up weeks or months late
and it shows signs of instability or early non
-union changes. That's also a clear indication
for surgical intervention, usually involving
bone grafting as well. Okay, so surgery is chosen
for stability, anatomical risk, proximal pull,
patient functional demands, or delayed presentation.
Let's dive into the surgical techniques themselves.
What are the main ways surgeons fix these fractures
operatively? The two primary surgical techniques
employed are open reduction internal fixation,
commonly known as ORIF and percutaneous screw
fixation. ORIF first, when is that needed? ORIF
is generally necessary for displaced fractures,
significantly angulated fractures, or complex
patterns where the surgeon needs direct visual
access to the fracture site to clean it out,
manipulate the fragments back into perfect alignment,
that's the open reduction part, and then hold
them there rigidly with internal fixation, usually
a screw. Okay, makes sense. Are there different
ways to approach the scaphoid for ORIF? Yes,
there are two main surgical approaches used for
ORIF, depending primarily on the fracture location.
The volar approach, meaning coming in from the
palm side of the wrist, is the real workhorse
for waist fractures. It's generally preferred
for these because it allows good access to the
waist and distal pole, and importantly, it helps
preserve that critical dorsal blood supply entering
the back of the bone. Protect the plumbing. Precisely.
The other main approach is the dorsal approach,
coming in from the back of the wrist. This is
usually necessary for proximal third fractures,
as it provides much better direct access to that
proximal fragment, which is hard to reach reliably
from the front. Right. Could you maybe walk us
through the VOLAR approach for an ORRF of a typical
waist fracture? What does that involve? Certainly.
The procedure is typically performed with the
patient lying supine, usually with the arm out
on an arm table, and almost always under tourniquet
control on the upper arm to provide a bloodless
surgical field. The incision is commonly made
longitudinally along the line of the flexor carpe
radialis or FCR tendon, which is easily palpable
on the front of the wrist. You carefully dissect
down through the layers, protecting vital structures
like branches of the radial artery and sensory
nerves, and retracting the thenar muscles, the
muscles at the base of the thumb, outwards. The
capsule of the wrist joint is then opened, often
along the FCR tendon sheath, to expose the scaphoid
waste. The fracture site is identified, cleaned
of any interposed soft tissue or blood clot,
and the fragments are carefully manipulated back
into their correct anatomical position. This
reduction is often achieved and held temporarily
using fine K -wires, sometimes used like little
joysticks. Once a surgeon is happy with the reduction,
confirmed perhaps with intraoperative x -rays
or fluoroscopy, a cannulated headless compression
screw is inserted. cannulated means it has a
hollow core, so you can be inserted over a pre
-placed guide wire. This guide wire is carefully
drilled down the central axis of the scaphoid,
ideally starting near the distal pole and aiming
proximally across the fracture line. Headless
screw. Yes. Headless means the screw doesn't
have a traditional bulky head. It's designed
so the entire screw can be buried just below
the level of the articular cartilage surface.
This is crucial to avoid the screw head impinging
on joint movement or damaging the opposing cartilage
surfaces later on. The screw is also designed
with differential pitch threads to actively compress
the fracture fragments together as it's tightened.
Clutter design? Very. Longer screws generally
provide better fixation stability across the
fracture. Now, if the fracture was significantly
comminuted, meaning broken into several pieces,
or if there was a pre -existing deformity like
a humpback that needed correcting during the
reduction, then bone grafting might be necessary
at this stage. Where does the bone graft come
from? Small amounts can often be harvested locally
from the distal radius bone near the wrist incision.
If a larger volume of graft is needed, it's typically
harvested from the patient's iliac crest, the
pelvic bone, through a separate small incision.
After the screw fixation and any necessary grafting,
the joint capsule and any important ligaments
that were incised, like the radioscapia capitate
ligament, are carefully repaired. Then the soft
tissues and skin are closed in layers. And what
happens postoperatively? Still a cast? Yes. Despite
the internal fixation, a period of immobilization
in a cast, usually a thumb spica, is still typically
required while the bone heals around the screw.
This is often for around six to eight weeks,
after which union is assessed radiographically,
usually with x -rays or maybe a CT scan, before
starting mobilization. That sounds like quite
a meticulous procedure. And the dorsal approach
for those challenging proximal pole fractures,
how does that differ? The dorsal approach is
quite different in terms of the structures you
encounter. It's typically performed via what's
called a 3 -4 approach, navigating between the
third and fourth extensor tendon compartments
on the back of the wrist. A midline incision
is usually made over the back of the wrist. The
sheath containing the extensor poleza longus,
EPL tendon, the long thumb extensor is opened,
and the EPL tendon is retracted radially towards
the thumb side. The main finger extensor tendons,
the extensor digitorum communus, EDC, are then
retracted a little gnarly towards the little
finger side. Okay, moving tendons out of the
way. Exactly. This exposes the dorsal wrist capsule,
which is then open, often over the scaffolding
joint interval. The wrist is often flexed significantly
downwards to bring the proximal pole of the scaphoid
into better view. A K -wire is then inserted,
usually starting just radial to the scaffolding
ligament itself, aiming from the small proximal
pole fragment down into the larger distal fragment,
sometimes provisionally driving it into the trapezium
bone distally for extra stability during screw
insertion. So coming from the top down, essentially.
Yes, aiming proximal to distal. Multiple fluoroscopic
views, AP, lateral obliques are absolutely essential
throughout this dorsal approach to confirm accurate
guide wire placement before drilling and inserting
the cannulated screw. It's technically demanding
because the proximal pole fragment can be quite
small and rotated. This approach is necessary
for most proximal pole fractures simply due to
their location and the need to access that specific
fragment directly for reduction and fixation.
Right. What are the union rates like for these
ORIF procedures, especially when used for those
unstable Herbert Type B fractures? For Herbert
Type B unstable fractures treated with ORIF,
the reported union rates are generally good,
certainly much better than casting alone for
these types, but they do vary slightly by the
specific subtype, reflecting those inherent biological
and mechanical challenges. Based on studies specifically
using the Herbert classification, union rates
for ORIF are often reported around 90 % for B1
distal oblique fractures. OK. Maybe 88 % for
B2 complete waste fractures, and slightly lower,
perhaps around 85%, for B3 proximal pole fractures.
Still. 85 % for the proximal pole with surgery
is pretty good, but it highlights the challenge.
It does. It highlights that even with optimal
surgical technique, proximal pole fractures remain
biologically more challenging to heal compared
to waist fractures, purely due to that vascular
issue. Now let's talk about the other main surgical
technique, percutaneous screw fixation. That
sounds less invasive than opening the wrist up
fully. It is, yes. And it's become increasingly
popular over the last couple of decades, particularly
for specific indications. Percutaneous screw
fixation involves inserting the fixation screw
through very small stab incisions, typically
just one or two, without formally opening the
joint capsule widely. What are the main advantages
of doing it that way? The key potential advantages
are even faster union rates, with some studies
reporting rates approaching 100 % in carefully
selected ideal cases. Also, potentially less
time required in a cast postoperatively compared
to ORF and consequently an earlier return to
activities including work and sport, which is
a major driver for certain patients. When is
percutaneous fixation indicated then? Is it suitable
for all types? No, it's primarily indicated for
acute minimally displaced scaphoid fractures,
usually waist fractures, where an anatomical
reduction can be achieved closed just by manipulating
the wrist and thumb, and crucially where this
position can be confirmed with high quality intraoperative
imaging. So not for badly displaced ones. Generally
not, as you can't directly see and manipulate
the fragments. It's especially appealing for
patients like manual workers or athletes who
have a strong need to minimize their time in
a cast and return to function as quickly as possible,
provided their fracture pattern is suitable.
Typically that minimally displaced waste fracture,
which is already in good alignment or can be
easily reduced closed. How is that technique
actually performed? If you're not opening it
up, how do you get the screw in the right place?
The patient setup is similar. supine arm table
tourniquet, but absolutely critical for percutaneous
fixation is the use of high -quality image intensification
fluoroscopy or live x -ray throughout the procedure
for precise guidance. Continuous x -ray vision.
Essentially, yes. Traction is often applied to
the thumb, sometimes using a finger trap device
to help distract the fracture fragments slightly
and align the scaphoid along its long axis. The
wrist is positioned carefully, often in ulna
deviation, and flexed over a bolster or roll,
again to bring the scaphoid into a straight orientation
relative to the fluoroscopy beam. Okay. A small,
volar, palm -side stab incision, maybe only five
millimeters long, is made over the palpable scaphoid
tuberosity distally. Through this tiny incision,
a guide wire is then very carefully inserted,
aiming along the central axis of the scaphoid
towards the proximal pole. This sounds like the
tricky part. It is the crucial step. Multineural
fluoroscopic views AP, lateral, and those 45
degrees obliques are used repeatedly and meticulously
to ensure the wire is perfectly positioned down
the central third of the bone on all views and
critically that it's not penetrating out through
the joint surfaces anywhere along its path. Once
the surgeon is completely satisfied with the
guide wire position, a cannulated drill is passed
over the wire to create the channel and then
the cannulated headless compression screw is
inserted over the wire. Often, a slightly shorter
screw length is chosen compared to the measured
length to ensure good compression is achieved
across the fracture site as the screw tightens.
Typically, screws around 24mm or 26mm are used
for the waist. In some cases, particularly for
longer oblique fracture patterns which might
have some rotational instability, a second, parallel
K -wire might be inserted percutaneously alongside
the screw guide wire just to provide some anti
-rotation stability. It sounds like navigating
that guide wire and screw perfectly within that
small awkwardly shaped bone purely using fluoroscopy
is the real art and challenge here, especially
avoiding poking out into the joint. Absolutely.
Accurate 3D placement based on 2D imaging is
paramount. The risk of unrecognized screw penetration
into the joint cartilage is a potential complication.
particularly if using many open techniques where
direct visualization is limited or perhaps with
less precise fluoroscopy. However, with modern
high -resolution fluoroscopy units and surgeon
experience, this risk is significantly reduced
compared to the earlier days of the technique.
Right. You mentioned earlier that bone grafting
is sometimes necessary, especially in ORF for
comminuted fractures or to correct deformity
like a humpback. Can we talk a bit more about
the role of bone grafting? Yes, bone grafting
plays a crucial role in several scenarios. It's
needed when there's actual bone loss at the fracture
site due to the injury mechanism or significant
comminution that creates a defect or gap after
you've reduced the main fragments. It's also
essential when treating an established non -union
where you need to bridge the gap and stimulate
healing. And as you mentioned, it's vital when
you need to correct a malunion deformity, like
surgically opening up a healed humpback. The
graft fills the wedge created by the corrective
osteotomy. What does the graft actually do? The
graft serves multiple purposes. Firstly, it acts
as a scaffold. providing structural support across
the defect. Secondly, and importantly, it introduces
osteoconductive properties, meaning it provides
a physical framework or trellis for the patient's
own new bone cells to grow across the gap. And
depending on the type of graft, it might also
provide some osteoinductive properties, meaning
it contains signaling molecules that actively
stimulate undifferentiated cells to become bone
-forming cells. osteoblasts. Some grafts even
provide osteogenic cells themselves. So structure
and stimulus. What types of bone grafts are typically
used for scaphoid surgery? We broadly divide
them into non -vascularized and vascularized
bone grafts. Non -vascularized grafts are simpler
in concept. You harvest bone from one site, the
donor site, and simply transfer it to the scaphoid,
the recipient site, without maintaining its original
blood supply. Okay, standard bone graft. Examples.
Common examples include the Rus -type inlay graft.
This is typically used for waist non -unions
approached via a volar incision, using struts
of corticocancelous bone, bone with both a hard
outer cortex and spongy, inner cancels part,
placed longitudinally across the non -union site.
This technique generally yields good union rates,
perhaps 85 -95 % for waist non -unions. Another
well -described non -vascularized graft is the
Fisk wedge graft, or sometimes called the Matty
-Roose technique. This often involves harvesting
a specifically shaped trapezoidal or triangular
wedge of bone, usually from the iliac crest,
which is then inserted into a surgically created
gap on the volar side of a malunited or non -united
scaphoid to correct a humpback deformity and
restore the scaphoid's normal length and alignment.
When this is combined with rigid internal fixation
like a screw, it can achieve very high union
rates, sometimes reported as 95 -100%. How is
a waste non -union managed specifically with
one of these non -vascularized grafts, say, using
the FIST technique to correct a humpback? Right,
so for a waste non -union, often with some humpback
deformity, a volar approach is usually preferred.
The non -union site itself is meticulously debrided.
That means all the fiber scar tissue and any
unhealthy sclerotic bone edges are removed using
sharp osteotomes or fine burrs, taking great
care not to damage the intact healthy dorsal
cortex if possible. Cleaning it out. Exactly,
preparing a healthy bed. During this debridement,
the surgeon carefully assesses the viability
of the bone fragments, particularly looking for
punctate bleeding from the proximal fragment,
tiny spots of blood welling up. which is a good
sign that it still has some blood supply remaining.
The paprika sign. Sometimes call that, yes. If
there's a humpback deformity, an osteotomy, a
controlled surgical cut, is made through the
milunian site, usually on the volar side, and
the defect is carefully opened up like a book,
correcting the angulation. The bone graft, harvested
maybe from the distal radius or iliac crest,
is then shaped precisely to fit the defect created
or to act as the wedge maintaining the correction.
It's then carefully inserted, ensuring good press
-fit contact with the healthy host bone on either
side. Provisional fixation is often achieved
with temporary K -wires, while the definitive
fixation, usually a cannulated headless screw,
is inserted across the graft and fracture site.
And the outcomes for non -union surgery like
this? While the union rates are generally good,
often around 90 % for waste non -unions treated
this way, It's important to note that patients
often have some residual loss of wrist range
of motion and perhaps some reduction in grip
strength compared to their uninjured side, even
after successful union. Treating an established
nonunion is always more complex than fixing an
acute fracture. You mentioned earlier that proximal
pole nonunions are even more challenging, even
with grafting. They are, unfortunately. Proximal
pole non -unions, which are typically approached
dorsally due to access, have historically had
significantly lower union rates when treated
with standard non -vascularized grafts alone.
Union rates are often cited in the literature
as being only around 67%, maybe 70 % at best.
That's quite a drop from the waste non -union
rates. It is. And this is where the concept of
using a vascularized bone graft, or VVG, becomes
particularly relevant and often necessary. Vascularized
bone grafting, right? This is where you transfer
the bone along with its attached blood vessel,
keeping it alive, correct? When is that specifically
indicated over a standard non -vascularized graft?
Precisely. A VBG is indicated in situations where
a standard non -vascularized graft is considered
less likely to succeed. This primarily means
proximal pulmon unions, and especially when there's
definite suspicion or clear confirmation of a
vascular necrothus, AVN, of that proximal fragment
on preoperative imaging like MRI. Because the
fragment is already dead or dying. Exactly. The
fundamental idea is to bring a new living blood
supply directly into the compromised vascular
bone fragment alongside providing the structural
bone graft itself. This aims to revitalize the
fragment and promote healing where a nonvascularized
graft might simply fail or become incorporated
very slowly, if at all. Does the evidence support
using VBG in these cases? Yes, quite strongly.
There was a key meta -analysis by Merrill published
in the Journal of Hand Surgery American Volume
back in 2002. which directly compared outcomes.
It demonstrated a significantly higher union
rate for proximal pole non -unions with AVN when
they were treated with a vascularized bone graft
around 88 % union compared to those treated with
non -vascularized bone graft, which only achieved
about 50 % union in that analysis. 88 % versus
50%. That is a compelling difference, isn't it?
It's a dramatic difference, yes. It really highlights
the biological power of bringing a dedicated
blood supply to a dying bone fragment. What are
the types of vascularized grafts that are commonly
used for the scaphoid? Where do they come from?
Several different techniques and donor sites
have been described over the years, but some
are definitely more common and widely used now.
A graft based on the pronator quadratus muscle
pedicle in the forearm used to be quite popular,
but seems to be used less frequently today, perhaps
due to variability in the vessel or technical
difficulty. Probably the most common vascularized
graft used currently for scaphoid non -union,
particularly for proximal pole issues or when
AVN is present, is a vascularized discal radius
graft. This is often based on the technique described
by Zeitemberg. Another very common and reliable
option, particularly popular in some centers,
is a vascularized graft harvested from the base
of the second metacarpal bone in the hand. Could
you briefly describe the Zeitemberg technique?
taking the graft from the distal radius, that
sounds quite accessible. Yes, it's an elegant
technique. This graft is based on a specific
small artery that runs on the back dorsal aspect
of the wrist. It's usually the 12 -2 intercompartmental
supranacular artery, a small branch of the radial
artery, or sometimes a 2S3 branch if the 12 -2
is very small or absent. This vessel travels
in the tissues just superficial to the extensor
compartments between the first and second, or
second and third compartments. A dorsal radial
surgical approach is used to carefully identify
and dissect out this small artery in its accompanying
veins, the vascular pedicle. You follow the pedicle
proximally down towards the distal radius bone,
where it can be seen to supply a patch of the
periosteum and underlying bone. Using a fine
osteotome, or saw, a small block or section of
cortico -canceled bone is then very carefully
harvested from the distal radius, ensuring that
the vascular pedicle remains attached and intact,
feeding into this piece of bone. Great care is
taken not to damage this delicate pedicle. The
scaphoid non -union site is then approached,
usually dorsally as we discussed. The non -union
is thoroughly cleaned out and prepared to receive
the graft. The vascularized bone graft, still
attached to its artery and vein, is then gently
transferred and rotated into the scaphoid non
-union site. You have to make sure the pedicle
isn't kinked, stretched, or compressed during
this transfer. So you're essentially bringing
a small living piece of radius bone with its
own blood supply and plumbing it into the scaphoid
defect. That's exactly the principle. It brings
its own perfusion. Fixation of the scaphoid fraction
on union site, usually with a compression screw,
is then performed to secure the graft firmly
in place and stabilize the construct. That's
fascinating surgery essentially replanting a
piece of bone with its plumbing intact. It's
clear that managing these established non -unions,
especially when AVM is involved, requires complex,
reconstructive surgical skills. We've touched
on them throughout our discussion, but let's
just consolidate the conversation specifically
on complications. What are the most serious issues
that can arise from a staphoid fracture, particularly
if it's missed or not managed correctly initially?
Yes. The serious complications are essentially
the consequences of failure to achieve timely
anatomical bony union. The most significant ones
we worry about are non -union itself, AVN, malunion,
and ultimately the development of post -traumatic
arthritis, often in the specific pattern known
as SNAC wrist. Let's take non -union first. How
common is it? Non -union, where the bone simply
fails to heal, unfortunately occurs in a proportion
of cases even with appropriate management. perhaps
5 -10 % overall for all scaphoid fractures treated.
But the rate is significantly higher for fractures
that were unstable to begin with, significantly
displaced, or located in the proximal pole, especially
if treatment was delayed or inappropriate, like
inadequate casting for an unstable fracture.
Are there other risk factors for non -union?
Yes, key risk factors beyond displacement and
location include certain fracture patterns, like
that vertical oblique pattern we mentioned, which
is prone to shear. Increasing patient age is
also a factor. And crucially, smoking or any
nicotine use is a major negative factor, as nicotine
is a potent vasoconstrictor and significantly
impairs bone healing potential. Treatment for
established non -union involves the surgical
strategies we've just discussed, primarily bone
grafting, often vascularized for the proximal
pole or if AVN is present. and AVN, the risk
we flagged right at the very beginning. How often
does that actually happen? Avascular necrosis,
or AVN, remains a major concern precisely because
of that vulnerable retrograde blood supply to
the proximal pole. The reporting incidence varies
quite widely in the literature, perhaps from
13 % up to 50 % overall, depending on the study
population and fracture types included. But particularly
high figures, up to 50 % are often quoted specifically
for proximal pole fractures. And the risk increases
dramatically with the amount of initial displacement.
OK. As cited in the source material, it can even
approach 100 % in fractures involving the most
proximal fifth of the scaphoid if they are treated
with immobilization alone. without surgical fixation
to restore stability and potentially improve
perfusion. And it's sneaky, isn't it? It doesn't
show up immediately. That's the insidious nature
of AVN. It often doesn't become apparent on standard
x -rays until months after the initial injury.
This is because it takes time for the bone to
slowly lose its viability, die, and then either
collapse or become relatively denser. sclerotic
compared to the surrounding living bone which
undergoes normal disuse osteoporosis in a cast.
This delay in radiographic appearance really
underscores why early accurate diagnosis of the
fracture type and risk factors, followed by appropriate
initial management, often surgery for proximal
pole fractures, is absolutely critical for trying
to prevent this devastating complication in the
first place. Once AVN is established, managing
it adds significant complexity and uncertainty
to the treatment. What about malunion when it
does heal but heals in the wrong position? Malunion,
which most commonly presents as that humpback
deformity with excessive flexion at the fracture
site, giving an intrascaphoid angle greater than
35 degrees on the lateral view, typically occurs
when an unstable or displaced fracture is treated
non -operatively. or perhaps when the reduction
achieved initially is lost within the cast and
the bone then heals in that abnormal flexed position.
What's the consequence of it healing bent like
that? The natural history, the long -term consequence
of this scaphoid malignant, is progressive carpal
instability. Specifically, it tends to lead to
that dizzy deformity pattern we mentioned, where
the lunate bone tilts backwards. This abnormal
alignment is followed by altered joint mechanics,
carpal collapse over time, increasing wrist pain,
reduced range of motion, especially extension,
decreased grip strength, and inevitably the development
of post -traumatic osteoarthritis. And the final
stage of that... It typically starts between
the tip of the radial styloid and the scaphoid
itself, then progresses to involve the scaphocapitate
joint. between the scaphoid and the large capitate
bone in the middle of the wrist, and finally
involves the capital lunate joint. By the time
a SNAC wrist pattern is fully established, the
joint surfaces are significantly damaged. At
this point, surgery aimed at achieving scaphoid
union is often no longer appropriate or even
possible, and treatment usually shifts towards
salvage procedures like wrist fusions or proximal
row carbectomy. It really represents the failure
to prevent the long -term consequences of the
initial scaphoid problem. A sobering endpoint.
Are there other complications to be aware of,
perhaps arising from the treatment itself? Yes,
certainly. Other potential complications include
delayed union, which is distinct from non -union.
This is where healing takes significantly longer
than expected, but is still biologically occurring.
Sometimes interventions like bone stimulators
using pulsed electromagnetic fields are tried
in these cases, although the evidence for their
effectiveness is somewhat limited and not universally
accepted. Hardware -related issues are possible
with surgery, such as irritation from a prominent
screw, or more seriously, subchondral bone penetration
by the screw tip, which can lead to cartilage
damage on the opposing joint surface and subsequent
arthrosis. While less common with modern screw
designs and careful fluoroscopic guidance, it
can occur and might require revision surgery
or implant removal. Infection is always a potential
risk with any surgical procedure, though thankfully
it's relatively infrequent after scaphoid surgery.
And despite achieving successful bony unions,
some patients may unfortunately experience persistent
symptoms like chronic pain, residual stiffness,
limiting function, or reduced grip strength compared
to their pre -injury state. It's worth noting,
once some A summary cited in the provided material
mentioned overall serious complication rates
being perhaps around 14 % in patients managed
operatively versus 18 % reporting cast -related
complications like stiffness, skin issues, nerve
compression in the non -operative treatment group.
This suggests risks exist down both pathways,
but importantly, the nature of the potential
complications differs significantly. Operative
intervention is often chosen specifically to
mitigate the higher risks of non -union and AVN
inherent to the unstable fracture types, even
though surgery carries its own set of potential.
all be different risks. That paints a very clear
picture of why prevention, early diagnosis, and
diligent appropriate management are so incredibly
crucial to avoid these serious, potentially life
-altering long -term issues. So, turning towards
the positive, what's the general prognosis and
recovery outlook for a scaphoid fracture that
is treated appropriately and in a timely manner?
Well, with timely and appropriate management
tailored to the specific fracture type, the prognosis
for most scaphoid fractures is generally good,
particularly for those stable undisplaced fractures
treated effectively with casting. What influences
the outcome? Key factors influencing the final
outcome include, naturally, the initial fracture
type and its location, proximal pole always being
less favorable, the presence and degree of displacement
or comminution, the presence of any associated
ligament injury causing carpal instability, the
chosen treatment method, cast versus surgery,
and importantly, patient factors like age, general
health, adherence to treatment, or particularly
their smoking status. You mentioned surgery might
get people back quicker. Yes. Surgical treatment,
when indicated and performed successfully, has
been shown in several meta -analyses to be associated
with a more rapid return to work and sorting
activities, compared to prolonged non -surgical
management in a cast, even for some fractures
that might otherwise have healed in a cast eventually.
That faster return is often a key factor in the
decision -making for athletes or manual laborers.
What's a typical recovery timeline look like?
The bone healing time itself Achieving solid
union typically ranges from 6 to 12 weeks, sometimes
longer for proximal pole fractures, depending
on the location and the type of treatment. However,
achieving full functional recovery, regaining
wrist range of motion, grip strength, and confidence
for demanding activities usually takes significantly
longer, often several months of dedicated rehabilitation
after the cast is removed or after surgery. So
patience is needed. Definitely. Follow -up with
periodic x -rays or sometimes CT scans is needed
to monitor the union progress until it's confirmed
solid. While some patients may experience some
minor residual stiffness or perhaps aching in
the wrist, especially in cold weather or after
heavy use, with successful union and appropriate
physiotherapy, chronic disabling pain and major
functional limitations are thankfully infrequent.
So, while it's undoubtedly a challenging fracture,
good outcomes are very much achievable with the
right approach. Finally, let's think about prevention.
Are there practical steps people can take to
reduce their risk of getting this injury in the
first place, or perhaps reduce the risk of complications
if they do sustain one? Yes, there are certainly
steps one can consider at different stages. Prevention
of the initial injury starts with basic safety
precautions, especially in activities known to
have a high risk of falls onto an outstretched
hand. Things like snowboarding, skateboarding,
rollerblading, or certain contact sports come
to mind. Wrist guards. Exactly. Wearing well
-fitting wrist guards during these activities
can significantly absorb the impact force and,
crucially, limit the degree of wrist hyperextension
during a fall, which can potentially prevent
the fracture from occurring. Also, just using
appropriate safety equipment generally and ensuring
safe environments during these activities is
key. What about people who are already involved
in sports or have had previous risk issues? For
individuals involved heavily in sports or demanding
manual labor, especially if they have a history
of previous risk pain or perhaps minor injuries,
tailored training and rehabilitation programs
can be beneficial. This might include exercises
to improve risk proprioception, your sense of
joint position, strengthening the muscles of
the forearm and thumb that support the wrist,
and maintaining good flexibility. And falling
technique. Yes, somewhat counter -intuitively.
Educating athletes and others at risk on techniques
to fall more safely learning how to tuck and
roll, for instance, to absorb the impact over
a larger body area rather than landing directly
onto a single outstretched hand can be a very
valuable preventative measure. Avoiding activities
that cause pain or strain seems pretty sensible,
too. Absolutely. If you start experiencing persistent
wrist pain or discomfort, particularly after
a fall or even just a minor incident, it's wise
to avoid activities that clearly exacerbate it.
Potentially using a supportive wrist splint temporarily
might help settle things down to prevent a minor
issue from becoming a more significant injury.
And seeking help if it persists. Crucially, yes.
After any wrist injury, Even if it is initially
dismissed as just a sprain, paying close attention
to persistent symptoms, especially that tenderness
in the anatomical snuff box, and seeking PROMP's
further medical evaluation and appropriate imaging
if it doesn't settle quickly is paramount to
avoid a missed or delayed diagnosis. And of course,
diligent follow -up care and maintaining open
communication with your health care provider
throughout the treatment and recovery process
are essential to catch any potential non -unions
or other complications early before they become
major harder to fix problems. Those are really
concrete, actionable steps listeners can consider.
We've covered a huge landscape today, haven't
we? From the spaphoid's really tricky anatomy
and blood supply, through all the nuances of
diagnosis, classification, the different surgical
techniques, including complex vascularized grafting,
and exploring those potentially devastating complications.
Let's try and boil this all down to the absolute
most crucial takeaways that you should remember
from this deep dive. Right. Let's try and crystallize
it. First, after any fall into an outstretched
hand, you must always suspect a scaphoid fracture
if there's tenderness in the anatomical snuff
box, period. Regardless of what the initial x
-rays might show or fail to show, high suspicion
is the very first step to avoiding disaster down
the line. OK, suspicion first. Second key takeaway.
Second, don't rely solely on standard basic x
-rays if your clinical suspicion remains high.
Be prepared to utilize advanced imaging promptly.
Use CT scanning for accurately assessing displacement,
combination, and monitoring union, and especially
use MRI for definitively diagnosing those occult
fractures or assessing for AVN when initial x
-rays are negative. Don't fall back on the two
-week wait. Right. Image appropriately. Third.
Third. Classification matters deeply because
it guides treatment. Understand that unstable
fractures, displaced 1 millimeter, angulated
35 degrees, comminuted vertically oblique patterns,
and particularly all proximal pole fractures,
carry a significantly high risk of non -union
and AVN. These types generally require surgical
fixation for the best, most predictable outcome.
Stable versus unstable, location, location, location.
Fourth, complications like non -union, AVN, malunion,
and the end -stage SNSC risk are serious life
-changing problems, but they're often preventable.
Timely, accurate diagnosis followed immediately
by appropriate evidence -based management casting
for the truly stable, surgery for the unstable
or high risk is the absolute key to mitigating
these long -term risks. Okay, prevention is key.
And finally, perhaps linking back to the start.
Prevention, where possible, through protective
measures like wrist guards and high -risk activities
and learning safer falling techniques, combined
with diligent follow -up care and simply listening
to your body after any wrist injury, plays a
vital role in maintaining long -term wrist health
and function. Don't ignore persistent wrist pain
after a fall. Excellent summary. That gives you
a really clear, deep understanding of why the
scaphoid fracture is absolutely not just a simple
break and what really needs to be done to manage
it effectively. If you found this deep dive valuable,
please do consider sharing it with your colleagues
on platforms like LinkedIn or X and perhaps leaving
us a rating. It genuinely helps us reach more
professionals who could benefit from this information.
And a huge thank you again to Professor Moimam
for sharing your incredible expertise and guiding
us through this very complex topic with such
remarkable clarity. It's been my pleasure. Important
topic. So as we wrap up, and considering all
the hidden dangers and potentially severe long
-term consequences we've discussed today for
this seemingly quite minor coin, perhaps the
final thought to leave you with is this. In the
face of such significant potential functional
loss down the line, are we consistently in our
clinics, on our sports fields, or perhaps in
our workplaces, giving every single wrist injury
the level of initial attention, diagnostic rigor,
and timely follow -through that the humble yet
absolutely critical scaphoid bone truly demands?