Latest / Deep Dive Ortho — Orthopaedic Surgery, AI & Digital Health Podcast. / Periprosthetic Fracture around Total Hip replacements

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Periprosthetic Fracture around Total Hip replacements · Deep Dive Ortho — Orthopaedic Surgery, AI & Digital Health Podcast.

0:00
All right, let's dive right into something that's
0:02
becoming, well, a major challenge in orthopedics,
0:05
especially with more and more people living longer,
0:07
having active lives. We're talking about fractures
0:10
around existing hip replacements. Now, these
0:13
aren't your typical broken bones. They present
0:14
a unique sort of puzzle for us in the medical
0:17
field. They really do. And the global rise in
0:20
these periprosthetic hip fractures, it's directly
0:22
linked to the incredible success and just the
0:26
sheer volume of total hip arthroplasties, THAs
0:29
being performed worldwide. What's also quite
0:32
fascinating is that we're seeing THAs not just
0:35
in the elderly, but increasingly in younger,
0:37
more active individuals. And that naturally broadens
0:40
the spectrum of potential complications, and
0:42
it challenges us to adapt, doesn't it? Absolutely.
0:45
It changes the game somewhat. And beyond the
0:47
immediate clinical complexity for the patient,
0:49
there's also a significant economic impact these
0:51
injuries have on health care systems. It's not
0:54
insignificant. Not at all. Today, we have Professor
0:56
Mo Imam with us, an expert guide who will help
0:58
us navigate this, well, intricate and evolving
1:01
area. Our mission for this deep dive is to give
1:04
you, our listener, a comprehensive, up -to -date
1:07
understanding of how these fractures are managed
1:10
right from the moment they're diagnosed through
1:11
to rehabilitation. It's truly a compelling area
1:14
because, you know, these fractures represent
1:16
a critical crossroads. It's trauma surgery meeting
1:19
arthroplasty. They demand a very specific combined
1:24
skill set from orthopedic surgeons, often pushing
1:27
the boundaries of our expertise. And their effective
1:31
management isn't just about technical surgical
1:33
skill, it truly requires seamless multidisciplinary
1:36
input to achieve the best, most lasting outcomes
1:39
for the patient. This isn't a problem one specialist
1:42
can solve alone. That immediately highlights
1:44
just how multifaceted this challenge is. So let's
1:47
begin by trying to understand the sheer scale
1:49
of the issue. Just how common are these periprosthetic
1:52
fractures? And what are the main factors putting
1:54
patients at such a heightened risk? Could you
1:56
give us a sense of the incidence and maybe the
1:59
typical mechanisms of injury we're seeing? Certainly.
2:02
Periprosthetic fractures around the hip, they
2:04
can occur during two distinct periods, either
2:07
intraoperatively so, right there on the operating
2:09
table during the surgery itself. Okay. Or post
2:11
-operatively, which is, you know, after the procedure
2:14
has been completed. Now, looking at intraoperative
2:17
fractures, they are notably more common in unsubstmented
2:21
total hip arthroplasties. We're talking about
2:23
roughly 5 .4 % of cases. 5 .4%, okay. Which stands
2:27
in stark contrast to cemented THAs, where the
2:31
incidence is much lower, maybe around 0 .3%.
2:33
Big difference. Huge difference. And what's particularly
2:36
striking is that this risk escalates significantly
2:39
during revision surgery. It jumps to an alarming
2:41
20. 0 .9%. Wow, 20%. Compared to a primary arthroplasty
2:46
where it's about 3 .6%. Now this tells us something
2:49
profound about the perhaps compromised bone quality
2:53
or the altered anatomy we often encounter in
2:55
those revision cases. Right, the underlying bone
2:57
isn't pristine anymore. Exactly. Then, postoperatively,
3:01
the incidence of paraprosthetic femoral fractures
3:03
is less than 1 % after a primary THA, which sounds
3:07
low, but it can rise to as much as 4 % following
3:10
revision surgery. So that indicates a kind of
3:13
cumulative risk over time. The overall lifetime
3:16
risk after any THA is estimated somewhere between
3:20
0 .4 % and 3 .5%. And it's crucial to understand
3:24
their significance in the bigger picture. These
3:26
fractures are the third most common reason overall
3:29
for THA revision. Third most common. Yes. And
3:32
interestingly, they climb to become the second
3:35
most common reason beyond the fourth year post
3:37
-primary THA. That's a trend consistently observed
3:40
in large national data sets, like the Swedish
3:43
national hip arthroplasty register, which gives
3:46
us invaluable long -term data. That long -term
3:49
perspective is key. It is. And while periprosthetic
3:52
femoral fractures are overwhelmingly the most
3:54
common type we discuss, it's worth remembering
3:56
that acetabular fractures affecting the hip socket
3:59
can also occur. Ah, yes. These are much rarer,
4:02
making up only about one -tenth of all THA -related
4:04
fractures. And they predominantly happen intraoperatively,
4:07
often to the force involved in planting a new
4:09
cup. Right, getting that cup seeded. Precisely.
4:12
As for the mechanism of injury for the post -operative
4:14
fractures, the vast majority, around 86%, result
4:18
from surprisingly low energy trauma. 86 % low
4:22
energy. Yes. We're talking about simple falls
4:25
from standing height. This isn't about high impact
4:27
car accidents in healthy individuals. It speaks
4:30
volumes about the fragility and often the comorbidities
4:34
present in this patient demographic. I find that
4:37
fascinating that these low energy falls account
4:39
for such a high percentage. It almost feels counterintuitive.
4:42
You'd expect high impact trauma, but it's often
4:45
the simple trip that causes the catastrophic
4:47
failure, isn't it? That's precisely the point.
4:49
It's often not a major external force, but an
4:52
underlying systemic vulnerability. Right. So
4:54
given that, what are the key patient related
4:56
risk factors that truly contribute to this underlying
4:59
vulnerability? Well, several patient characteristics
5:01
consistently contribute to an increased risk.
5:04
Female gender and advanced age are frequently
5:06
cited, largely due to age -related bone density
5:08
loss and higher rates of osteoporosis. However,
5:12
it's worth noting that while these are common
5:13
associations, the evidence across the literature
5:16
can sometimes be a bit inconsistent on their
5:18
independent impact. Ah, okay. Nuance there. Exactly.
5:22
But what is consistently identified are certain
5:24
underlying medical conditions. Ochaeoprosis,
5:27
of course, is a significant one, but also rheumatoid
5:30
arthritis, Paget's disease, and developmental
5:33
hip dysplasia, all of which compromise bone quality
5:36
and integrity. Crucially, an increased time from
5:39
the initial archerplasty procedure is also a
5:42
significant factor, as implants' age, bone remodels,
5:46
and bone quality can naturally deteriorate over
5:48
decades. So the longer you have the hip replacement,
5:51
the higher the risk, potentially? Potentially,
5:53
yes. The cumulative risk increases. Beyond these
5:55
specific diagnoses, age -linked comorbidities,
5:59
particularly osteoporosis and cognitive decline,
6:01
pose substantial and compounding challenges.
6:04
Osteoporosis, as you might expect, doesn't just
6:06
make fractures more likely. It also makes them
6:09
significantly harder to stabilize once they occur.
6:11
The bone itself just lacks the structural integrity
6:13
for screws or plates to hold securely. Right.
6:16
Fixation becomes a real issue. A major issue.
6:19
And cognitive decline, on the other hand, creates
6:21
this cascade of risks. It impairs a patient's
6:24
judgment and balance, making falls more frequent.
6:27
But it also profoundly impacts their ability
6:30
to understand and comply with the complex post
6:33
-surgical regimens, things like weight -bearing
6:36
restrictions or specific movements, which are
6:39
absolutely vital for successful recovery and
6:42
preventing further complications. It's a truly
6:44
holistic risk picture, you see. It sounds like
6:47
a deeply intertwined web of patient health and
6:49
as you touched upon, the implant itself. On that
6:52
note, what about the implant design and the surgical
6:54
technique itself? How do those contribute to
6:56
the risk profile? Are there certain choices or
6:58
technical considerations that increase or decrease
7:01
the likelihood of these fractures? Indeed. Implant
7:03
design and the meticulousness of surgical technique
7:06
play a profound role. Several key factors here
7:08
are well established. Stem malposition during
7:11
the initial surgery, for instance. Ah, placement.
7:14
Exactly. Where the femoral stem isn't aligned
7:16
perfectly, that can create stress risers in the
7:18
bone, making it more prone to fracture. Pre -existing
7:22
osteolysis, that's bone loss due to where particles
7:25
from the implant or asymptotic loosening of the
7:27
implant, means the bone around the prosthesis
7:30
is already compromised before any trauma occurs.
7:32
Right, it's weakened. It's weakened already.
7:34
And the patient's surgical history specifically,
7:37
the number of previous surgeries to the same
7:38
region also increases risk, often due to altered
7:42
anatomy, scarring, and reduced blood supply.
7:44
Now, when we delve into implant types, cementless
7:48
femoral implants have been consistently associated
7:51
with a higher incidence of periprosthetic fractures,
7:54
both during the surgery itself and in the postoperative
7:57
period. Okay, cementless specifically. Yes. For
8:00
example, studies have indicated that intraoperative
8:02
fractures occur up to 14 times more often with
8:05
uncemented components. 14 times? Wow. It's significant.
8:09
And this risk is particularly pronounced in female
8:12
patients over 65 years old who receive unsubmitted
8:15
components, highlighting a specific vulnerable
8:18
subgroup. While postoperative fractures are also
8:21
more common with unsubmitted implants, interestingly,
8:24
this seems to be independent of age and gender.
8:26
Interesting. Specific implant designs also matter
8:29
significantly. There's been a notable three -fold
8:32
increase in periprosthetic fracture rates observed
8:34
with single -wedge and double -wedge implants
8:37
when compared to anatomical, fully -coated, or
8:40
taper -drowning components. For shape matters.
8:42
The shape and how it engages the bone absolutely
8:44
matters. The difference lies in how these stems
8:47
engage with the bone and distribute stress. For
8:50
cemented implants, exitotype, or force -closed
8:53
stems, which are designed to subside slightly
8:56
into the cement mantle, creating stability through
8:58
a wedge effect. They tend to show a higher risk
9:01
of periprosthetic fracture than charnel type
9:03
or composite beam stems. Charnel type aim for
9:06
more rigid fixation and distribute stress differently
9:09
along the bone cement interface. It's a fundamental
9:12
difference in biomechanical philosophy that directly
9:15
impacts how the implant interacts with the bone
9:17
and consequently its susceptibility to fracture.
9:21
That makes sense. And lastly, Paraprosthetic
9:23
acetabular fractures are typically linked to
9:25
unsubmitted press -fit elliptical cups, again
9:28
due to the mechanics of their initial fixation.
9:30
So yes, the choice of implant, its precise placement,
9:33
and its inherent biomechanical properties are
9:36
absolutely paramount. That level of detail on
9:39
implant mechanics is crucial. Now, once a fracture
9:41
is suspected, the initial assessment is, as you
9:44
said, absolutely critical. What's involved in
9:47
thoroughly evaluating these cases? And how do
9:49
classification systems guide your decision making,
9:52
especially considering the challenges you mentioned
9:54
in preoperative stability confirmation? Right,
9:56
the initial clinical and radiological assessment
9:59
is the absolute cornerstone of managing these
10:01
complex cases. It always begins with a detailed
10:04
clinical history and a thorough examination.
10:08
Most patients present following a low -energy
10:10
trauma, so establishing that clear context is
10:12
vital. However, it's equally crucial to dig deeper
10:16
and ascertain if there were any pre -existing
10:18
worsening symptoms before the acute injury. Ah,
10:21
like warning signs. Exactly. Things like persistent
10:24
thigh pain, the notorious start -up pain, or
10:27
groin pain. These could be subtle indicators
10:29
of an already loose or failing prosthesis, which
10:33
would fundamentally alter your management strategy.
10:35
A critical, often overlooked step is actively
10:38
ruling out infection. periprosthetic joint infection,
10:41
or PGI. It's been reported in about 11 .6 % of
10:44
periprosthetic fractures. 11%, that's quite high.
10:47
It is, and it can be devastating. However, a
10:50
significant challenge is that standard inflammatory
10:52
markers like white cell count, ESR, and CRP,
10:55
while healthful, have been shown to have, well,
10:58
poor predictive value for deep PGI. So they aren't
11:00
reliable enough on their own? Not always, no.
11:03
If clinical suspicion for PGI is low, we typically
11:06
proceed with surgery. taking multiple intraoperative
11:08
tissue samples for culture and histology to confirm.
11:12
But if there's a high clinical suspicion based
11:14
on the patient's history or exam, preoperative
11:17
aspiration and biopsies are strongly recommended
11:19
to guide subsequent antibiotic and surgical planning.
11:22
You need that information up front. Makes sense.
11:24
Radiological imaging is, of course, vital. Full
11:27
-length X -rays of the entire femur extending
11:29
from the hip to the knee and a comprehensive
11:31
pelvis view are essential. These allow us to
11:34
determine the fracture's precise location, its
11:36
characteristics as it's spiral, transverse, commonoted,
11:40
and crucially, to assess the prosthesis' stability
11:43
and, for cemented components, the integrity of
11:46
the cement mantle. It's also incredibly helpful
11:49
to retrieve all previous imaging, if available.
11:52
A patient's radiological history can often reveal
11:54
subtle signs of component migration or pre -existing
11:57
osteolysis, guiding us to potential weak spots.
12:00
Looking for changes over time. Exactly. A CT
12:03
scan is also standard practice now. It provides
12:05
more detailed information on bone stock, the
12:08
exact fracture pattern in three dimensions, and
12:11
the integrity and stability of the components,
12:12
especially around the stem. Now, regarding the
12:16
challenge of preoperative THA stability confirmation,
12:18
you hit on a key point. There's a reported 20
12:21
% discrepancy between what we think we see on
12:24
preoperative imaging and what we actually find
12:26
intraoperatively. 20%. That's a big gap. It's
12:29
a significant gap. Indirect methods such as assessing
12:33
distal implant translation or using fluoroscopy
12:36
in the clinic are often inconclusive if they
12:38
are negative. Ultimately, the most reliable method
12:40
remains the hands -on intraoperative assessment
12:43
during surgical exploration. So you really only
12:45
know for sure once you're in there? Pretty much.
12:48
This 20 % discrepancy isn't just a number. It
12:51
fundamentally shifts how surgeons must approach
12:53
these cases. It forces an extraordinary level
12:56
of intraoperative adaptability. A true test of
12:59
surgical intuition, beyond what any scan can
13:02
tell you beforehand. It highlights the art as
13:04
much as the science of orthopedics. This is why
13:06
thorough planning with clear contingency strategies
13:09
is absolutely crucial. You have to be ready for
13:11
Plan B or even Plan C. That 20 % unknown is enough
13:15
to keep any surgeon up at night, isn't it? So
13:17
once you have that comprehensive assessment,
13:19
understanding these nuances, How do classification
13:22
systems like the Vancouver system help guide
13:24
precise management decisions, especially given
13:26
those diagnostic challenges you highlighted?
13:29
Indeed, it emphasizes the need for surgical readiness.
13:32
Classification systems are absolutely fundamental
13:34
to guiding management. They provide a common
13:36
language and a framework. The Vancouver classification
13:38
system remains by far the most widely used and
13:41
accepted system for femoral pair prosthetic fractures.
13:45
It's rather elegant in its simplicity, categorizing
13:48
fractures based on three key parameters. The
13:50
precise location of the fracture relative to
13:52
the implant, the stability of the implant itself,
13:55
and the quality of the surrounding bone. Okay,
13:57
location, stability, bone quality. Precisely.
14:00
To quickly summarize its main types, AG describes
14:03
fractures of the greater trochanter, AL for the
14:05
lesser trochanter. Then we move into the more
14:07
complex B types, which are around the stem. B1
14:10
indicates a fracture where the implant is stable.
14:12
B2 means the implant is unstable. And B3 signifies
14:16
an unstable implant combined with poor, deficient
14:18
bone stock. Okay, B1 stable, B2 unstable, B3
14:21
unstable, plus bad bone. You've got it. Finally,
14:25
type C fractures occur well below the stem tip.
14:28
However, despite its widespread utility, the
14:31
Vancouver classification has its limitations.
14:34
A significant finding from a Swedish study, for
14:36
instance, revealed only a 34 % agreement between
14:39
surgeon and radiologist classifications for B1
14:41
fractures. Only 34 % agreement? That's low. It
14:45
is surprisingly low. Yeah. And it dramatically
14:48
highlights the real challenge in accurately differentiating
14:51
a B1 from a B2 based solely on radiographs before
14:54
surgery. This again underscores why intraoperative
14:57
assessment of stem stability through direct palpation
15:00
and manipulation is absolutely paramount to confirm
15:03
the classification and therefore guide the definitive
15:06
treatment. So the x -ray gives you a clue, but
15:08
the final decision is made in theater. Essentially
15:10
yes. Beyond Vancouver, the Unified Classification
15:13
System, or UCS, is a newer, more comprehensive
15:16
system. It's designed to classify all paraprosthetic
15:19
fractures, regardless of their anatomical site,
15:21
so not just the hip. It's shown strong intra
15:23
-observer agreement for experienced orthopedic
15:25
surgeons around .920, which is good, but notably
15:29
lower for residents at .772, indicating there's
15:32
a learning curve. Right. It's a broader role
15:34
in everyday clinical decision -making versus
15:36
research is still being thoroughly evaluated.
15:39
We also have other... more specific systems,
15:42
such as the Poprosky system and Pasquerella et
15:44
al.'s method, tailored specifically for periprosthetic
15:47
acetabular fractures. These systems provide a
15:50
vital framework, but as you rightly pointed out,
15:53
profound clinical judgment, continuously informed
15:56
by intraoperative findings, is always the ultimate
15:59
guide. So we've nailed down how to classify these
16:02
fractures, but the real challenge, the art of
16:04
orthopedics, begins now. Yeah. Choosing the right
16:07
weapon for the right battle. Because, as you've
16:09
highlighted, a Vancouver B3 is a world away from
16:12
an AG fracture. How do you even begin to tailor
16:15
a strategy when there's no true one -size -fits
16:18
-all for such varied injuries? What are those
16:20
fundamental principles guiding your approach
16:22
to optimal management? You've perfectly articulated
16:24
the core dilemma. There's simply no cookbook
16:27
for these cases. A highly individualized approach
16:30
is utterly essential. Treatment decisions must
16:33
carefully consider a whole constellation of factors.
16:36
The patient's existing comorbidities, are they
16:39
diabetic? Do they have cardiac issues? What were
16:42
their functional levels before the fracture?
16:44
What's the confirmed stability of the implant?
16:46
And critically, what are the available resources
16:49
and surgical expertise? That last point is important,
16:52
isn't it? Not every hospital has the same kit
16:55
or experience. Precisely. Not every center has
16:57
the same level of specialized equipment or surgeon
17:00
experience with complex revisions. And not infrequently,
17:03
multidisciplinary input is critical, often involving
17:06
geriatricians, infectious disease specialists,
17:08
or intensivists. There's a growing recognition
17:11
of the need for focused clinical pathways for
17:13
paraprosthetic fractures, mirroring what we've
17:16
successfully implemented for other fragility
17:18
fractures like native hip fractures. Ah, like
17:20
the neck of femur pathways. Yes, exactly. This
17:23
signifies a systemic evolution in how we approach
17:26
comprehensive care, moving beyond just the immediate
17:30
surgical fix to a more holistic standardized
17:32
patient journey. Historically, non -operative
17:36
treatment of paraprosthetic fractures has generally
17:38
been associated with pretty dismal outcomes.
17:41
We're talking non -unions, malunions, and significantly
17:44
increased medical complications. This is why
17:47
operative intervention is now overwhelmingly
17:48
the contemporary choice for almost all cases.
17:52
The only real exceptions are critically ill patients
17:54
who simply cannot physiologically withstand major
17:56
surgery. However, it's worth noting some newer
18:00
emerging evidence on anabolic drug therapies
18:02
like teraparotide combined with specific non
18:05
-operative protocols. Even for very minimally
18:07
displaced B2 fractures, this could potentially
18:10
offer an alternative for extremely frail patients
18:13
who are otherwise inoperable. Still early days,
18:15
perhaps. Interesting potential development there.
18:17
It is. Once surgical treatment is decided, several
18:20
fundamental principles come into play. Meticulous
18:23
preoperative planning is paramount. And this
18:26
isn't just a cursory glance at x -rays. It involves
18:28
detailed revision templating, virtually placing
18:31
implants on images to plan size and position,
18:34
and verifying that all appropriate surgical kits,
18:37
including revision instruments and possible backup
18:39
implants, are physically available in the hospital.
18:42
Checking the kit beforehand is vital. Absolutely.
18:45
The surgical approach must be chosen carefully
18:47
to minimize soft tissue damage, preserving the
18:49
critical blood supply to the bone. And, given
18:52
the potential for unexpected findings, particularly
18:55
with that 20 % discrepancy we discussed, having
18:58
robust backup plans for different scenarios is
19:00
always essential. This truly highlights the necessity
19:02
of having combined advanced trauma and arthroplasty
19:05
skills within the operating team. You need both
19:07
skill sets. You really do. The overarching aim
19:10
of the procedure is always consistent. Restore
19:13
anatomical alignment with a stable implant. preserve
19:16
existing bone stock wherever possible, promote
19:19
predictable fracture union, and, crucially, enable
19:22
early patient mobilization and preservation of
19:25
joint motion. The specific choice of implant
19:28
and technique is then ultimately guided by the
19:30
fracture's precise location and complexity, the
19:33
prosthesis's confirmed stability, and the quantity
19:36
and quality of remaining bone stock. all balanced
19:39
against individual patient factors like their
19:41
physiology, bone healing potential, and any existing
19:45
comorbidities. That's a remarkably comprehensive
19:47
framework. Let's talk specifics now, starting
19:49
with Vancouver type A fractures, which involve
19:52
the proximal trochanteric region. How are these
19:55
typically managed and what are the nuances for
19:57
each subtype? Right, Vancouver type A fractures
20:00
are typically the least complex. They involve
20:02
either the greater trochanter, classified as
20:04
AG, or the lesser trochanter, AL. For AG fractures
20:08
involving the greater trochanter, these are generally
20:10
considered stable fractures. They're very often
20:13
managed not operatively. So no surgery usually?
20:16
Often not. Just a period of protected weight
20:18
bearing and restricted active hip abduction for
20:20
approximately 6 to 12 weeks. This allows the
20:23
trochanter to heal in place. However, surgical
20:26
fixation, using simple techniques like wires,
20:28
cables, or small, speculized plates, becomes
20:30
indicated if there's a symptomatic nonunion,
20:32
meaning persistent pain, or functional issues
20:35
like limping or weakness. OK. Or if there's significant
20:39
migration of the trochanter fragment, typically
20:41
defined as more than 2 centimeters displacement.
20:44
And if the fracture is also associated with particle
20:47
-induced osteolysis, which is that bone loss
20:49
to -to -wear particles, the underlying osteolysis
20:53
must also be addressed. Right, tackle the root
20:54
cause. Exactly. Depending on the extent of bone
20:57
loss and the stability of the main implant, this
21:00
might range from a simple bearing surface exchange
21:02
with bone grafting to a full acetabular and femoral
21:05
stem revision. As for AL fractures affecting
21:08
the lesser trochanter, these are usually treated
21:11
non -operatively, similar to undisplaced AG fractures.
21:14
Also non -op usually. Yes. The rationale here
21:17
is that the lesser trochanter is often not critical
21:19
for hip stability. Surgical intervention is typically
21:22
only considered if the fracture is unusually
21:25
large and extends into the calcar region of the
21:27
femur, potentially compromising the stability
21:30
of the main stem. In such rarer cases, circlage
21:33
wiring, where wires are wrapped around the bone
21:35
to provide compression with or without grafting,
21:38
or even stem revision with diaphysial fixation,
21:42
may be necessary. If an ale fracture occurs and
21:45
is identified intraoperatively, which is common
21:47
due to instrument placement, circlage wiring
21:49
is usually advised immediately to prevent displacement,
21:52
followed by a period of protected weight bearing
21:54
post surgery. So, relatively less invasive approaches
21:57
for type A fractures unless there are those specific,
21:59
complicating factors. Now let's move to Vancouver
22:02
type B fractures, which you noted are arguably
22:04
the most challenging category and certainly the
22:06
most prevalent. How do you approach these, starting
22:08
with B1, where the prosthesis is stable but the
22:11
bone around it is fractured? Yes. Type E fractures
22:14
truly represent the bulk of the challenge. They
22:16
account for the vast majority, with B1 at maybe
22:19
29 % and B2 at 53 % in some large registries
22:23
like the Swedish hip arthroplasty register. So
22:25
B2 is the most common overall? It often appears
22:28
to be yes. The difficulty often lies in accurately
22:31
determining the prosthesis' stability and the
22:33
bone stock quality, even interoperatively. For
22:37
subtype B1 fractures, which occur around a stable
22:39
prosthesis, the conventional approach is indeed
22:42
open reduction and internal fixation, or RIF,
22:46
primarily using extra medullary devices such
22:48
as plates and circlage cables. Fixing it with
22:50
plates and wires. That's the traditional idea.
22:53
However, this approach comes with significant
22:55
inherent challenges. These extramedulary implants
22:57
were off -axis load -bearing devices. This means
23:00
they are exposed to incredibly high -bending
23:02
stresses, particularly when the patient begins
23:05
weight -bearing. Ah, the physics work against
23:07
you. They do. Combined with the typically slow
23:10
bone healing process in elderly patients who
23:12
often have osteoporotic bone, this can frequently
23:16
lead to early fatigue failure of the plating
23:18
system before bony union is achieved. The very
23:21
nature of osteopenic or osteoporotic bone, coupled
23:24
with the existing stiff implant or cement mantle,
23:28
severely complicates screw anchoring and fixation.
23:31
It substantially increases the risk of mechanical
23:33
failure. The screws just don't hold well enough.
23:36
Exactly. There's also the potential for the existing
23:38
cement mantle to fracture during screw insertion
23:41
and a negative impact on the already compromised
23:43
intramedullary blood supply due to prior reaming
23:46
or the exothermic reactions of cement. So, to
23:49
address these issues, modern techniques often
23:51
favor bridging locking plates. These plates act
23:54
as strong extra medullary bridging splints, creating
23:56
a fixed angle construct that is ideal for osteopenic
23:59
bone. Locking plates. How do they help? Well,
24:01
they are considered more biologically friendly
24:03
because they don't rely on plate -to -cortex
24:05
friction or precise screw thread purchase for
24:07
stability. They lock into the plate, providing
24:10
angular stability. This preserves the crucial
24:13
periosteal blood supply. Contemporary plates
24:16
feature anatomical designs, variable interlocking
24:19
options that allow surgeons to navigate around
24:21
the existing stem, extensions for trochanteric
24:24
fragments, and multi -directional screw placement
24:27
to target available healthier bone. These can
24:30
often be applied using minimally invasive plate
24:32
osteosynthesis or MIPO techniques. MIPO, so smaller
24:37
incisions. Yes, further reducing soft tissue
24:39
damage and preserving that vital blood supply.
24:41
Studies consistently show excellent union rates
24:44
and reduce complications with MIPO compared to
24:47
traditional open approaches for B1s. Crucially
24:50
though, surgical parameters must be meticulously
24:53
observed. Plate working length. That's essentially
24:56
how much of the plate bridges the fracture, should
24:58
ideally be two to three times the width of the
25:00
femur at the fracture level. Too short, and you
25:02
concentrate stress. Too long, and you might unnecessarily
25:05
stiffen the bone, risking a fracture at the plate
25:07
ends. Similarly, plate span width for Combinated
25:11
fractures dictates the length of the plate relative
25:14
to the shattered bone segment, typically two
25:17
to three times the fracture length. And critically,
25:20
plate screw density, aiming for less than 0 .5,
25:22
means strategically spacing your screws to distribute
25:25
load evenly and prevent stress risers that could
25:28
lead to early fatigue failure, especially in
25:30
compromised bone, spreading the load precisely.
25:33
While bicortical fixation is biomechanically
25:35
superior, if not possible, a combination of circle
25:38
-ish wires or cables for bending resistance,
25:41
combined with unicortical locking screws for
25:43
torsion and axial compression, can be used. And
25:46
a key rationale today is to use long plates that
25:49
span the whole femur. Sometimes even the entire
25:51
diaphysis. Protecting the whole bone. Yes, to
25:54
protect against future injuries, as these patients
25:56
are unfortunately prone to subsequent falls and
25:58
new stress risers. So, MIPO and advanced locking
26:01
plates are truly changing the game for B1 fractures,
26:04
allowing for more biologically friendly and robust
26:06
fixation. But you mentioned a fascinating paradigm
26:10
shift, even within B1, where revision might be
26:13
preferred over fixation despite a stable prosthesis.
26:16
That's truly counterintuitive. What's the biggest
26:19
hurdle for surgery? margins in making that shift
26:21
away from simply fixing a B1, and in what specific
26:24
scenarios does this alternative approach become
26:26
the superior choice? That's a really insightful
26:28
question, and it gets to the heart of evolving
26:30
surgical philosophy. The biggest hurdle is often
26:33
the initial inclination to preserve an apparently
26:36
stable, well -integrated femoral stem. You think,
26:40
well, why dismantle something that appears to
26:41
be working? Exactly. Seems like more surgery.
26:44
It is more surgery initially. However, for some
26:46
particularly challenging B1 fractures, revision
26:49
arthroplasty with a long stem, essentially acting
26:51
as an intramedullary splint, can genuinely be
26:54
a more effective and durable strategy. This is
26:57
especially true for short, oblique, or transverse
27:00
B1 fractures located precisely at the stem tip,
27:03
or very combinated fractures right there. Ah,
27:05
the really awkward ones at the tip. Precisely.
27:07
With an extramedullary plate alone, the construct
27:10
remains an off -axis load -bearing system. Achieving
27:13
optimal biomechanical strain at the fracture
27:15
site, especially where stress transitions acutely
27:18
from the very stiff proximal segment, which includes
27:20
the well -fixed existing stem and the proximal
27:23
part of the plate to the distal femoral fragment,
27:25
can be exceedingly difficult. This often leads
27:28
to delayed healing, non -union, or plate fatigue
27:31
failure, requiring further surgery down the line.
27:34
So the plate fix might fail eventually. It has
27:37
a higher risk of failing in those specific scenarios.
27:40
In these challenging B1 cases, the decision shifts
27:43
towards a more pragmatic approach. While it means
27:46
a greater initial surgical intervention by revising
27:49
an otherwise stable femoral stem, this is often
27:51
counterbalanced by the biomechanically advantageous
27:54
in -axis load sharing provided by the new, longer
27:57
femoral stem. This revised stem should extend
28:00
well beyond the fracture by passing the fracture
28:02
level by at least two cortical diameters, ideally
28:05
more, to act as a strong internal splint. Using
28:07
the new stem as the fixation. Exactly. Essentially
28:11
for these challenging B1s, the decision shifts
28:13
from a technically simpler fix to a patient -specific
28:17
strategy that prioritizes overall long -term
28:19
survival, earlier and safer mobilization, and
28:23
a more uneventful post -operative course. It
28:26
reduces the likelihood of repeat surgery. It's
28:28
about looking beyond the immediate fracture and
28:31
considering the entire biomechanical system and
28:33
the patient's overall journey. That's a profound
28:35
strategic shift. Now, if B1s can be this complex,
28:39
what happens when you're dealing with an unstable
28:41
prosthesis, as in subtype B2? But you still have
28:44
decent bone stock. How does that shift the treatment
28:47
paradigm? Right. For subtype B2 fractures, where
28:49
the prosthesis is confirmed to be unstable, but
28:51
the surrounding bone stock is still adequate,
28:53
the consensus approach is generally a long -stem
28:55
revision archroplasty. Revision is the main plan
28:58
here. Yes, generally. This is often supplemented
29:00
by additional plate fixation and or allograft
29:03
strut fixation to help consolidate the fracture.
29:06
Evidence strongly supports this. Systematic reviews
29:09
and data from national registries, such as the
29:11
SAR again, consistently show significantly higher
29:14
re -operation rates for B2 fractures treated
29:17
with RIF alone, around 32 % compared to a much
29:20
lower 10 % for those treated with revision surgery.
29:23
Big difference in re -operation rates. Huge.
29:26
This is because fixing the fracture without addressing
29:28
the underlying unstable implant is often doomed
29:31
to failure. The loose stem will just continue
29:34
to move and prevent healing. In these revision
29:36
surgeries, the choice of stem is crucial. Long
29:39
porous coated cementless stems or tapered fluted
29:42
modular titanium known as TFMT stems are very
29:45
commonly used due to their excellent discal fixation
29:47
capabilities in the healthier bone further down.
29:49
Getting fixation distally. Exactly. For very
29:52
frail or unreliable patients, or those with more
29:55
distal fracture extension and poorer bone stock
29:58
distally, cemented stems can also be considered.
30:02
They offer immediate stability for early weight
30:04
bearing, which can be critical in that group.
30:06
And as with B1 fractures requiring revision,
30:09
the new stem should bypass the most distal fracture
30:11
line by at least two cortical femoral diameters
30:14
to provide sufficient stability and protection
30:17
against refracture. Now there's an interesting
30:19
and unique nuance for periprosthetic fractures
30:22
that occur around cemented, polished tapered
30:25
stems, which are common implants like the Exeter
30:27
stem. Ah, the tapered ones. Yes. Due to their
30:30
design principle, they are forth closed and rely
30:33
on controlled subsidence into the cement mantle.
30:36
These stems are, by their very nature, inherently
30:38
unstable when a fracture occurs around them.
30:41
So while revision with a new long stem is still
30:43
considered the gold standard, or IFF alone can
30:46
sometimes be a viable option if the fracture
30:48
is reducible and the existing cement mantle is
30:50
well fixed to the bone. So fixing the bone might
30:52
be enough if the cement is solid? Potentially,
30:55
in selected cases. This approach can be less
30:57
demanding surgically, quicker, and potentially
31:00
involve less blood loss, which can be advantageous
31:02
for very sick or elderly patients. Some studies
31:05
have shown good results with this ORIF alone
31:07
approach in specific patient groups. However,
31:09
it's critically important to acknowledge that
31:11
other studies have reported higher non -union
31:13
rates when ORIF is used for B2 fractures, especially
31:17
if the underlying instability isn't fully accounted
31:19
for. It's a calculated risk. And, as I mentioned
31:22
earlier, for very frail, inoperable patients
31:24
with minimally displaced B2 fractures, anabolic
31:27
agents might even be considered for conservative
31:29
management, particularly around these specific
31:32
cemented stems. The key is truly individualized
31:35
decision making based on the whole picture. So
31:37
while revision arthroplasty is the undeniable
31:40
gold standard for B2s, there are indeed specific,
31:43
highly selected scenarios where ORF can be a
31:45
viable, less invasive alternative. What happens
31:48
then with subtype B3 fractures, where you're
31:51
dealing with both an unstable prosthesis, and
31:53
a severe, inadequate bone stock? This sounds
31:57
incredibly challenging, almost like trying to
31:59
build on sand. You've hit the nail on the head.
32:01
Subtype B3 fractures are exceptionally challenging,
32:04
precisely because of that combination. A loose
32:07
prosthesis and massive bone deficiency. It is
32:10
indeed often like building on crumbling ruins.
32:13
A real reconstructive nightmare. It can be. The
32:16
primary treatment options typically involve major
32:18
femoral component revision, often requiring techniques
32:21
like using a proximal femoral allograft that's
32:24
cadaver bone. Right. Or even a proximal femoral
32:26
replacement, where you replace the whole top
32:28
end of the femur with metal. Impaction grafting,
32:31
where a morselized bone graft is tightly packed
32:33
into defects, can also be used effectively for
32:36
large, contained bone defects, essentially rebuilding
32:38
the foundation. Surgeons have an array of specialized
32:41
implants available for these complex reconstructions.
32:45
Fully portis -coated stems, tapered fluted stems,
32:48
modular or monoblock designs, distally locking
32:51
stems, and as I said, dedicated proximal femoral
32:53
replacement prostheses. Lots of options, but
32:55
complex ones. Very complex. The key here isn't
32:59
just having these implants, but surgeon familiarity
33:01
with the chosen system and the ability to apply
33:04
a reproducible meticulous surgical technique,
33:07
often refined over many years. Achieving adequate
33:10
distal stem stability in the dysphysial bone
33:13
is paramount. Sometimes it's the only healthy
33:15
bone available for fixation. Meticulous preoperative
33:18
templating along with careful intraoperative
33:21
assessment of leg length and overall stability
33:23
is crucial to prevent postoperative issues. It's
33:26
also vital to preserve as much proximal metaphysical
33:29
bone as possible, even if it's fractured, and
33:31
to wrap the remaining femur with its soft tissue
33:33
attachments around the new prosthesis. This provides
33:36
biological stability and optimizes muscle function.
33:39
Trying to solid everything you can. Absolutely.
33:42
Allograft prosthetic composites, which combine
33:44
a cadaveric bone segment and allograft with a
33:47
new prosthesis, can be invaluable for massive
33:49
bone loss. particularly in younger patients where
33:53
long -term durability and bone stock restoration
33:55
are priorities. These can be used with uncemented,
33:58
cemented, or partially cemented techniques depending
34:00
on the specific case. And finally, for older
34:03
patients with severe bone efficiency or very
34:05
poor prognosis, a proximal femoral replacement
34:08
despite a relatively high complication rate and
34:11
the sheer magnitude of the surgery can sometimes
34:13
be the only viable option to get them mobilized.
34:16
A last resort in some ways. In some ways, yes.
34:19
These B3 cases They are often the ones that truly
34:22
test a surgeon's mettle, not just technically,
34:24
but in terms of resourcefulness and judgment.
34:27
You have to be prepared for almost anything,
34:29
knowing you might be trying to build a stable
34:30
foundation on what often feels like crumbling
34:32
ruins. It's clear that B3s demand an extraordinary
34:35
level of reconstructive surgery and planning.
34:38
Now, moving away from the area immediately around
34:41
the stem, what about Vancouver type C fractures,
34:44
which occur well below the implant tip? How do
34:46
these differ in their management strategy? Right.
34:49
Vancouver type C fractures are distinct because
34:51
they are located in the distal third of the femur,
34:54
well below the femoral stem. Typically more than
34:57
two to three times the femoral diameter discol
35:00
to the implant tip. Critically, these fractures
35:03
do not compromise the stability of the hip prosthesis
35:06
itself, which remains well fixed proximally.
35:09
So the hip joint part is okay? Exactly. Therefore,
35:12
the primary treatment involves open reduction
35:14
and internal fixation using standard osteosynthesis
35:17
techniques. Mostly bridge plating or, less commonly,
35:21
retrograde nailing from the knee end. The key
35:23
principle here is that while the hip prosthesis
35:25
itself is stable, its presence in the proximal
35:27
femur must be accounted for to minimize the risk
35:30
of secondary fractures or stress risers forming
35:33
between the hip stem and the new fixation distalate.
35:35
Ah, avoiding a weak spot in the middle. Precisely.
35:38
Even if a short plate might appear biomechanically
35:41
adequate for the immediate fracture, the contemporary
35:43
consensus born out of experience is to protect
35:46
the entire diaphysis by overlapping the femoral
35:49
component proximally. Anchoring proximally with
35:52
crooklish cables or screws around or past the
35:54
tip of the stem, this approach ensures a better
35:56
balance of the construct's working length, plate
35:59
span width, and crew ratio, distributing stresses
36:02
more evenly across the bone. More importantly,
36:05
it provides crucial protection against future
36:07
injuries. You're thinking ahead again. Yes, as
36:10
these patients are highly susceptible to subsequent
36:12
falls that could easily lead to new fractures
36:14
if parts of the diaphysis are left unprotected,
36:16
creating a new stress riser at the end of a short
36:18
plate. Therefore, most surgeons now prefer to
36:21
span the whole femur with a long retrograde locking
36:24
plate, ensuring maximum fixation at the distal
36:26
metaphysis and a combination of screws and cables
36:29
proximally. This is about preventing the next
36:31
fracture, not just fixing the current one. So
36:33
we've taken a deep dive into femoral periprosthetic
36:36
fractures, which are undoubtedly the most common
36:39
and challenging. But what about those equally
36:42
demanding, albeit less frequent, fractures involving
36:45
multiple implants, known as interprosthetic femoral
36:48
fractures, or those affecting the acetabulum?
36:51
Let's start with interprosthetic femoral fractures.
36:54
Right. Interprosthetic femoral fractures or IFFs.
36:57
These are defined as fractures occurring between
36:59
an ipsilateral hip and knee implant. So a hip
37:02
replacement and a knee replacement on the same
37:04
leg. Exactly. And the fracture happens in the
37:06
femur shaft between those two prostheses. While
37:09
still relatively uncommon, they represent a growing
37:12
challenge in our practice. They account for about
37:15
5 % to 7 % of all paraprosthetic femoral fractures,
37:18
and their incidence will certainly rise as more
37:20
patients receive both implants. That makes sense.
37:22
Classification is absolutely key here to guide
37:25
treatment. Pyres et al.'s 2014 classification
37:28
is considered the most comprehensive. It strategically
37:31
divides IFFs into three major categories based
37:35
on the fracture location, the stability of both
37:37
the hip and knee implants, and importantly, whether
37:40
there's a stemmed knee femoral component, as
37:42
this significantly impacts reconstructive options.
37:45
This system then provides a guiding treatment
37:48
algorithm based on these variables. So it considers
37:50
both ends? Precisely. For management, if both
37:53
the hip and knee implants are stable, then fracture
37:56
fixation is the primary approach, with locking
37:58
plates being the implant of choice due to their
38:01
versatility and fixed angle stability. However,
38:04
if either the hip or knee implant or both are
38:06
unstable, then revision arthroplasty of the unstable
38:09
component is necessary, often supplemented by
38:12
internal fixation to stabilize the fracture itself.
38:14
Right, address the loose bit first. You have
38:16
to. For complex or severe cases, especially those
38:20
with significant comminution or bone loss, various
38:23
composite constructs, including intramedullary
38:25
options where a rod is placed inside the bone
38:27
and strike grafting, can provide both intra -
38:30
and extramedullary stability. A critical surgical
38:33
principle, regardless of the chosen strategy,
38:36
is to bypass the fracture adequately, avoid creating
38:38
new stress risers at the ends of implants, and
38:41
ideally span the entire femur between the two
38:43
prostheses, or at least overlap the prosthesis
38:46
by at least two cortical diameters beyond the
38:49
fracture. In the most severe cases, particularly
38:51
certain pyres types, especially with poor bone
38:53
stock, options can include advanced arthroplasty
38:56
with adjuvant fixation or even total femur replacement.
38:59
That's a truly massive reconstructive procedure.
39:01
Releasing the whole thigh bone. Essentially,
39:04
yes. The outcomes for IFFs can be quite challenging,
39:07
reflecting the complexity of these injuries and
39:09
the often frail patient population. Reported
39:12
non -union rates are around 8%, with mortality
39:15
rates around 6 .5 % and revision rates for failure
39:18
at about 10 .7%. However, it's worth noting that
39:21
some studies, such as Bonviale et al.'s series,
39:24
have reported significantly higher mortality
39:26
rates, up to 31%, and revision rates of 24%.
39:30
31 % mortality? That's very high. It is sobering.
39:33
These statistics truly underscore the fragile
39:35
nature of this patient cohort and the absolute
39:38
necessity for meticulous planning and execution
39:40
to avoid catastrophic failures. Those mortality
39:43
rates are indeed sobering, highlighting the severe
39:45
challenge these fractures pose. Now, turning
39:48
our attention to the acetabulum at the socket
39:50
side, periprosthetic acetabular fractures are
39:53
less common, but I imagine equally, if not more,
39:57
severe and challenging to treat. What are the
39:59
unique aspects of these injuries? Absolutely.
40:02
Periprostatic acetabular fractures, while less
40:05
common than the femoral ones, present profound
40:07
challenges to the surgeon. Their incidence is
40:09
also expected to rise with the increasing numbers
40:12
of elderly and more active individuals undergoing
40:14
THA. These fractures can occur either intraoperatively,
40:18
during the primary or revision surgery, or postoperatively.
40:23
Intraoperatively, they are most frequently associated
40:25
with uncemented press fit elliptical cups. The
40:28
uncemented cups again? Yes, where the force of
40:31
insertion can cause micro -fractures or larger
40:33
breaks. They're also more common during revision
40:35
THRs than primary ones, often due to a combination
40:39
of patient factors like severe osteoporosis and
40:42
surgeon -related technical challenges in working
40:44
with altered anatomy or removing old components.
40:47
Post -operatively, they can result from high
40:49
-energy trauma or more commonly from severe bone
40:52
loss due to underlying conditions like osteoporosis,
40:55
aseptic loosening of the implant, osteolysis,
40:58
pelvic discontinuity we will discuss in a moment,
41:00
malignancy or infection. So similar underlying
41:03
causes to femoral fracture sometimes. Similar
41:05
risk factors, yes, but manifesting in the pelvis.
41:08
For classification, the Proprosky system is commonly
41:11
used, describing various types based on the extent
41:14
and location of bone loss and fracture patterns.
41:17
Pascarella et al. have also presented a comprehensive
41:20
system that guides surgical planning based on
41:22
the timing of diagnosis, the stability of the
41:25
acetabular prosthesis, and the pre -injury arthroplasty
41:28
state. Diagnosis requires a highly comprehensive
41:31
approach to identify and precisely classify the
41:34
fracture and, crucially, determine the stability
41:36
of the implant. Interoperative fluoroscopy can
41:39
be immensely useful to confirm reduction and
41:42
fixation during surgery. Postoperatively, patients
41:45
typically present with significant pain, loss
41:47
of function, reduced range of motion, inability
41:50
to weight -bear, or a leg -length discrepancy.
41:52
In acute traumatic injuries, there's even a potential
41:55
for life -threatening hemorrhage due to the rich
41:57
vascularity of the pelvis. Bleeding is a major
42:00
risk there. A very significant risk. Imaging
42:03
includes plane radiographs, standard AP pelvis,
42:07
Judith views, which highlight specific pelvic
42:08
columns, and inlet -outlet views and CT scans
42:12
with 3D reconstruction. These are essential to
42:15
provide detailed information on the fracture
42:16
pattern, the extent of bone loss, and the relationship
42:19
of the implant to the bone. In cases of severe
42:22
displacement, CT and geography may even be recommended
42:24
to rule out potential vascular injuries. So once
42:27
diagnosed, what are the core treatment principles
42:29
for these acetabular fractures? Especially given
42:32
the complexities of bone stock and component
42:33
stability, it sounds like a delicate balance
42:35
between fixation and revision. That's precisely
42:38
the challenge. The fundamental treatment principles
42:41
for perprostetic acetabular fractures revolve
42:44
around achieving a stable acetabulum that can
42:47
adequately support the component, preventing
42:49
any micromotion at the implant bone interface.
42:52
This almost always necessitates adequate bone
42:55
stock with or without additional augmentation
42:58
to ensure secure implantation and long -term
43:01
stability. For intraoperatively identified fractures,
43:05
If they are undisplaced and the cup is stable,
43:08
they can sometimes be left in situ with standard
43:10
rehabilitation. But supplemented screw fixation
43:14
of the cup is generally recommended to provide
43:16
additional stability and reduce the risk of secondary
43:18
displacement. Add a few screws for safety. Usually
43:21
a good idea. If the cup is unstable and there's
43:24
fracture displacement, the meticulous open reduction
43:26
and posterior column plating followed by the
43:28
insertion of a revision cup is advised. For missed
43:31
intraoperative fractures, which can happen, close
43:33
follow -up with serial radiographs is critical
43:35
to monitor for any delayed displacement or cup
43:38
migration, which would then necessitate revision
43:40
surgery. Keep a close eye on them. Definitely.
43:42
For postoperative fractures, acute traumatic
43:45
undisplaced fractures with a stable cup may initially
43:49
be treated conservatively with protected weight
43:51
bearing and gentle mobilization. However, close
43:55
follow -up with serial radiographs is mandatory
43:57
due to the insidious risk of secondary loosening
44:00
even if the fracture appears to heal. So even
44:03
if it looks okay initially? It can loosen later.
44:06
If that occurs, revision surgery over consolidated
44:09
bone may be needed. However, if the fracture
44:11
fails to heal, or if there's an unstable fracture
44:14
pattern with an unstable component, then prompt
44:17
ORF, most often posterior column fixation combined
44:20
with revision surgery, is unequivocally required.
44:23
And what about pelvic discontinuity, which sounds
44:25
particularly severe. Can you elaborate on what
44:27
that is and how it's approached? Pelvic discontinuity,
44:30
or PD, is indeed a particularly challenging condition.
44:33
Imagine the acetabulum, the socket of the hip
44:35
joint, actually detaching or splitting from the
44:37
rest of the pelvis, essentially losing its structural
44:39
integrity in both the anterior and posterior
44:41
columns. The whole socket breaks away. Effectively,
44:44
yes. It's a catastrophic failure of the bone
44:47
that normally supports the hip cup, making reconstruction
44:50
incredibly complex because you're trying to reestablish
44:52
a stable ring from what is now two separate fragments.
44:56
Treatment for PD is highly individualized, factoring
44:59
in bone quality and quantity, the soft tissue
45:01
environment, and the patient's overall health
45:03
and functional demands. Rogers et al. proposed
45:07
a useful algorithm distinguishing between acute
45:09
and chronic discontinuity. Acute, mobile discontinuities
45:13
are typically treated with RAF and revision surgery,
45:16
aiming to anatomically reduce and fix the fracture
45:18
while simultaneously revising the unstable cup.
45:22
Chronic, more rigid discontinuities where the
45:24
fragments have healed in a malunited or non -united
45:26
position often require a more extensive approach,
45:29
commonly a cupcage reconstruction. What's that?
45:32
It's essentially a mel construct, often made
45:34
of titanium, that bridges the gap between the
45:37
separated pelvic fragments and provides a stable
45:39
platform to cement or fix a new cup into. It
45:42
bypasses the deficient bone. Other options for
45:45
managing pelvic discontinuity include the use
45:47
of robust column plates to bridge the defect,
45:50
structural grafting to fill bone voids, anti
45:53
-pertrusio cages to prevent the cup from migrating
45:55
inwards into the pelvis, or jumbo cups, often
45:58
combined with porous trabecular metal augments,
46:01
particularly for cases with good healing potential
46:03
and minor bone loss. For chronic cases with little
46:07
inherent support and poor of vascular bone, distraction
46:10
techniques like a cupcage are often invaluable.
46:13
They literally bridge the gap, allowing bone
46:15
to potentially heal around them and create a
46:17
new stable bridge. In situations of truly massive
46:20
bone loss, a triflange component, which is a
46:23
custom -made implant based on the patient's CT
46:25
scan, is typically required. It essentially rebuilds
46:28
the complex pelvic anatomy with metal flanges
46:30
that fix the remaining healthy bone. Extremely
46:36
complex. Other techniques might include impaction
46:39
grafting, non -cemented hemispherical reconstruction,
46:43
structural allografts though largely superseded
46:45
by porous metal augments, now oblong cups, or
46:49
other cages like Gans and Virtschneider or the
46:52
Kerbal Tanaka Plate. The key is selecting the
46:55
technique that best reestablishes the structural
46:57
integrity of the acetabulum and allows for secure
47:00
long -term cup fixation. We've covered a remarkable
47:03
amount of ground on the clinical management and
47:05
the sheer technical complexity. So what does
47:08
this all mean for the patient in the long run?
47:10
Given these complexities, what are the typical
47:12
outcomes? And crucially, what are we doing as
47:15
a field to prevent these fractures in the first
47:17
place? And what does the future hold for orthopedic
47:19
practice in this area? Right, the overall outcomes
47:22
and complications for periprosthetic hip fractures
47:24
really highlight their significant impact on
47:26
patients' lives. In the acute phase, these fractures
47:29
carry a mortality risk comparable to that of
47:32
native neck of femur fractures in the elderly.
47:34
Same mortality as a standard hip fracture. Initially,
47:37
yes, which is a stark comparison. We see a one
47:40
-year mortality rate reported at around 9 .7%.
47:43
This risk does seem to decrease significantly
47:45
after the initial six months post -surgery, which
47:48
suggests that critical early period is key. The
47:50
overall 30 -day complication rate is notably
47:52
high at 45%, with a concerning 22 % being major
47:56
complications and 13 % minor, and a 30 -day mortality
48:00
rate of 10%. 10 % mortality in 30 days. Yes.
48:03
It's critical to note that significant risk factors
48:05
for these adverse outcomes include a patient's
48:07
abbreviated mental test score, or AMTS, of 8
48:10
out of 10 or less, indicating some level of cognitive
48:12
impairment and a delay to surgery of more than
48:15
72 hours. So cognition and timing matter hugely.
48:18
Absolutely. This underscores the need for rapid
48:21
assessment and intervention, as well as comprehensive
48:23
geriatric co -management. Functional and radiological
48:27
outcome data are somewhat limited, largely due
48:29
to the wide diversity of fracture types, the
48:32
varied treatment approaches, and the high morbidity
48:34
and mortality rates inherent in this patient
48:36
population, not to mention characteristics like
48:38
those low AMTS scores. However, studies generally
48:41
indicate that patients undergoing revision for
48:43
periprosthetic fractures tend to have worse functional
48:46
outcomes compared to those revised simply for
48:48
aseptic THA loosening. Worse function than a
48:51
standard revision? Generally, yes. Functional
48:54
impairment is common, with studies showing around
48:56
41 .9 % of patients may not return to their pre
48:59
-injury walking status. That's a truly significant
49:02
impact on their quality of life. The most unfavorable
49:05
prognosis in terms of both survival and functional
49:08
return is typically seen after a B3 fracture,
49:11
given the extent of bone loss and surgical complexity
49:14
involved. As for arthroplasty longevity after
49:16
these revisions, long -term data are rather sparse
49:19
due to the high mortality and restricted follow
49:21
-up in this frail cohort. Though short - to mid
49:24
-term studies generally report high union rates
49:26
in stable implants, we need more long -term data.
49:29
Beyond the immediate outcomes, infection is always
49:32
a major concern in orthopedic surgery, and I
49:34
imagine paraprosthetic joint infection, or PJI,
49:37
is a critical and potentially devastating complication
49:40
here. What's the situation with PJIs in this
49:43
context? PGI is indeed a critical complication,
49:46
and its incidence is unfortunately rising in
49:48
parallel with the increasing number of arthroplasty
49:50
procedures globally. This leads to significant
49:52
morbidity and mortality, and the cost of treatment
49:55
is truly substantial, particularly in regions
49:57
with limited health insurance access. It's a
49:59
huge burden. A massive burden. Effective management
50:02
demands a high level of teamwork, involving a
50:04
dedicated multidisciplinary team. That includes
50:07
microbiologists, histobiologists, pathophysiologists,
50:11
working alongside orthopedic surgeons, often
50:13
guided by clear radiological imaging and comprehensive
50:16
laboratory results. Diagnosis relies on a combination
50:20
of strong clinical evidence and, crucially, identifying
50:23
the causative organism. Preoperative testing
50:26
typically includes hematological markers such
50:28
as ESR and CRP, advanced imaging like x -rays,
50:32
maybe PD scans, and synovial fluid analysis looking
50:35
at cell counts, leukocyte esterase, and most
50:38
importantly, cultures. However, intraoperative
50:41
tissue samples, taken from multiple sites within
50:43
the joint during surgery, are vital for definitive
50:45
diagnosis and identifying the specific pathogen.
50:48
Newer methods such as PCR are also becoming more
50:51
available, offering quicker and potentially more
50:53
sensitive detection. Getting the right bug is
50:55
key. Absolutely essential for targeted treatment.
50:59
The treatment algorithm for PJI is complex. For
51:02
acute infections occurring soon after surgery,
51:05
debridement, antibiotics and implant retention,
51:07
or DARE, is often considered. However, for infections
51:11
older than three weeks, where biofilms have likely
51:14
established on the implant surface, a multi -stage
51:16
approach, often guided by algorithms like Zimmerle's,
51:20
may be necessary. Biofilms make it much harder.
51:22
Much harder. In some severe intractable cases,
51:26
a salvage operation like arthrodesis, fusion
51:28
of the joint, or even amputation might be the
51:31
only option left. The most common choice among
51:33
surgeons, and generally considered the gold standard
51:35
for chronic PGI, is a two -stage exchange. Two
51:38
stages? How does that work? The first stage involves
51:40
complete removal of the implant, thorough debridement
51:43
of all infected and devitalized tissue, and temporary
51:45
installation of an antibiotic -impregnated cement
51:48
spacer into the joint space. A spacer with antibiotics.
51:51
Yes, delivering high local concentrations. After
51:54
an interim waiting period, typically two to six
51:57
weeks or even longer, allowing systemic antibiotics
52:00
to take effect and infection markers to normalize.
52:03
The second stage involves implanting a new prosthesis
52:06
and taking further tissue biopsies to confirm
52:09
infection eradication. Patients usually receive
52:12
a prolonged course of oral antibiotics, often
52:14
for six weeks or more, following the second stage.
52:17
It's also important to consider special patient
52:19
conditions, like immunosuppression or cognitive
52:22
decline, and country -specific challenges, such
52:25
as delayed presentation due to financial constraints
52:27
or limited access to certain antibiotics in developing
52:30
nations, all of which complicate effective management.
52:33
That's a comprehensive yet daunting approach
52:35
to managing a potentially devastating complication.
52:38
Given all these challenges, what proactive prevention
52:40
strategies are being implemented? And what does
52:43
the future hold for this field? Prevention is
52:45
absolutely crucial for patients' success and
52:48
to mitigate the rising burden of these fractures.
52:50
It starts long before surgery and continues long
52:53
after. Patient education, for instance, isn't
52:55
just handing them a leaflet. It's a deep dive
52:58
into realistic expectations, the absolute necessity
53:01
of compliance with rehabilitation protocols,
53:03
and a clear understanding of their physical limitations
53:06
and risks. We often involve physical therapists
53:09
in preoperative counseling to design personalized
53:12
home exercise programs, emphasizing not just
53:15
strength, but balance and proprioception to prevent
53:17
falls. Preventing the falls in the first place.
53:20
Exactly. And it's not just about what they do
53:22
after surgery. It's about optimizing their overall
53:24
bone health, now ensuring adequate calcium and
53:27
vitamin D intake, maybe even considering anti
53:30
osteoporotic medications like bisphosphonates
53:32
or teraparitide, if indicated. We also stress
53:35
environmental modifications, simple but critical
53:37
things like securing rugs, improving home lighting,
53:41
installing grab bars and bathrooms. It's a holistic
53:43
approach to fall prevention, recognizing that
53:45
one bad fall can undo all the surgical success.
53:48
Simple things can make a big difference. They
53:50
really can. Preoperative assessments are also
53:53
essential to identify high -risk patients. those
53:56
with atypical anatomy, significant fixed deformities,
53:59
or leg length discrepancies allowing us to tailor
54:01
prophylactic measures or choose specific implant
54:04
designs to minimize risk. During surgery, meticulous
54:07
implant positioning and fixation, maintaining
54:10
an impeccably sterile environment, and early
54:12
controlled mobilization are key to reducing post
54:15
-operative complications. Looking to the future,
54:18
the evolution of orthopedic implants continues
54:20
at a rapid pace, providing more surgical options.
54:23
However, there's a clear and ongoing need for
54:26
even more specially designed implants that can
54:28
better address the vast majority of paraprosthetic
54:30
fractures, particularly those with complex geometry
54:33
and significant bone loss. Better tools for the
54:35
job. Exactly. New concepts in fracture fixation.
54:39
such as plates with far cortical locking, which
54:41
offer unique biomechanical advantages by engaging
54:44
the opposite cortex. And active plating, where
54:47
the plate itself provides dynamic compression,
54:49
are emerging. These will require robust clinical
54:52
evidence and long -term studies to thoroughly
54:54
evaluate their outcomes in practice. The significant
54:57
remaining challenge is the limited robust data
55:00
on long -term functional outcomes and implant
55:02
longevity following revision surgery for periprosthetic
55:06
fractures. This is critical, especially as their
55:09
incidence is projected to continue rising. Interprosthetic
55:12
and periprosthetic acetabular fractures, while
55:15
currently less common, represent growing challenges
55:18
that demand further dedicated research and evidence
55:20
-based guidelines. Ultimately, the substantial
55:23
financial burden these complex injuries place
55:25
on healthcare systems globally highlights an
55:27
ongoing and pressing need for more effective,
55:29
predictable solutions. and perhaps a potential
55:32
move towards specialized regional centers to
55:34
provide optimal cost -effective care for these
55:36
highly complex cases. So, what does this all
55:39
mean for us as medical professionals? The management
55:42
of paraprosthetic hip fractures remains one of
55:44
the most complex and critical areas in orthopedic
55:47
surgery today. It's abundantly clear that successful
55:50
outcomes hinge on a deeply individualized approach.
55:53
One that seamlessly combines highly advanced
55:56
surgical skills with comprehensive patient assessment,
55:59
rigorous risk stratification, and meticulous
56:02
post -operative care. As the number of total
56:05
hip arthroplasties continues to rise globally,
56:07
so too will the incidence of these challenging
56:09
fractures, meaning this will remain a focal point
56:12
for decades to come. The ongoing need for innovation
56:15
in implant design, refined surgical techniques,
56:18
and robust long -term data for our decision -making
56:21
simply cannot be overstated. If you found this
56:24
deep dive valuable, please do take a moment to
56:26
rate and share this deep dive with a colleague
56:27
who might benefit. Join us next time on the deep
56:30
dive as we continue to explore the cutting edge
56:32
of medical knowledge. This raises an important
56:34
overarching question for all of us in the field,
56:36
doesn't it? How can we further collaborate across
56:39
disciplines and national borders to standardize
56:41
best practices, share learnings, reduce complications,
56:44
and ultimately improve not just survival, but
56:47
the meaningful quality of life for this increasingly
56:49
frail and complex patient population? The journey
56:53
of mastering paraprosthetic fracture management
56:55
is an ongoing one, a continuous learning curve
56:58
for us all.