Date post: | 05-Apr-2018 |
Category: |
Documents |
Upload: | mukunth-iyer |
View: | 223 times |
Download: | 0 times |
of 25
8/2/2019 Acetabulum Set 5 p 81
1/25
FRACTURE OF ACETABULUM
The acetabulum can be described as an incomplete hemispherical socket with
an inverted horseshoe-shaped articular surface surrounding the
nonarticular cotyloid fossa.
This articular socket is composed of and supported by two columns of bone,
described by Letournel and Judet as an inverted Y.
The anterior column is composed of the bone of the iliac crest, the iliac
spines, the anterior half of the acetabulum, and the pubis.
The posterior column is the ischium, the ischial spine, the posterior half of
the acetabulum, and the dense bone forming the sciatic notch.
The column concept is used in classification of these fractures and is central
to the discussion of fracture patterns, operative approaches, and internal fixation.
The dome, or roof, of the acetabulum is the weight bearing portion of the
articular surface that supports the femoral head
Anatomical restoration of the dome with concentric reduction of the
femoral head beneath this dome is the goal of both operative and nonoperative
treatment.
The quadrilateral surface is the flat plate of bone forming the lateral border
of the true pelvic cavity and thus lying adjacent to the medial wall of the
acetabulum.
The iliopectineal eminence is the prominence in the anterior column that lies
directly over the femoral head.
Both the quadrilateral surface and the iliopectineal eminence are thin and
adjacent to the femoral head, limiting the types of fixation that can be used
in these regions
8/2/2019 Acetabulum Set 5 p 81
2/25
Two-column concept of Letournel used in classification of acetabularfractures
The neurovascular structures passing through the pelvis are at riskduring the
original injury and subsequent treatment, and the various surgical approaches are
designed around these structures.
The sciatic nerve exiting the greater sciatic notch inferior to the piriformis
muscle frequently is injured with posterior fracture-dislocations of the hip
and fractures with posterior displacement
The functioning of both the tibial and common peroneal components of the
sciatic nerve must be carefully documented in the emergency department and
after subsequent interventions
8/2/2019 Acetabulum Set 5 p 81
3/25
The superior gluteal artery and nerve exit the greater sciatic notch at its
most superior aspect and can be tethered to the bone at this level by variable
fascial attachments.
Fractures that enter the superior portion of the greater sciatic notch can be
associated with significant hemorrhage, possibly requiring angiography withembolization of the superior gluteal artery.
Knowledge of the intrapelvic relationships of the lumbosacral trunk, common and
external iliac vessels, and inferior epigastric vessels as well as of the obturator
artery and nerve becomes crucial as retractors, reduction forceps, drills, and
screws are used.
One particularly noteworthy anatomical relationship is the occasional large
anastomosis between the external iliac artery or inferior epigastric artery
and the obturator artery known as the corona mortis
Failure to ligate this vascular connection during the ilioinguinal approach
can lead to significant hemorrhage that is difficult to control as the external iliac
vessels are mobilized.
RADIOGRAPHIC EVALUATION
The acetabulum is evaluated radiographically with an AP pelvic view as well as
with the 45-degree oblique views of the pelvis described by Judet and
Letournel, commonly calledJudet views.
In the iliac oblique view, the radiographic beam is roughly perpendicular to
the iliac wing.
In obturator oblique view, radiographic beam is roughly perpendicular to the
obturator foramen.
Inclusion of the opposite hip in the radiographic field on the anteroposterior
and Judet views is essential for evaluation of symmetrical contours that may
8/2/2019 Acetabulum Set 5 p 81
4/25
have slight individual variations and to determine the width of the normal
articular cartilage in each view.
The medial clear space between the femoral head and the radiographic
teardrop in the injured and uninjured hips should be compared on the
anteroposterior view as an indication offemoral head subluxation.
Fractures that traverse the anterior columndisrupt the iliopectineal line,
whereas fractures that traverse the posterior column disrupt the ilioischial
line.
Landmarks of standard anteroposterior radiograph of hip.
1. Iliopectineal line beginning at greater sciatic notch of ilium and extending down
to pubic tubercle.
2. Ilioischial line formed by posterior four fifths of quadrilateral surface of ilium.
3. Radiographic teardrop composed laterally of most inferior and anterior portion
of acetabulum and medially of anterior flat part of quadrilateral surface of iliac
bone.
4. Roof ofacetabulum.
5. Edge ofanterior lip ofacetabulum.
6. Edge ofposterior lip of acetabulum.
8/2/2019 Acetabulum Set 5 p 81
5/25
A, Obturator oblique view of hip. B, Iliac oblique view of
hip.
In the operating room, the three standard views can be obtained with
fluoroscopy.
The restoration of the radiographic landmarks is a guide to the adequacy offracture reduction.
The anatomical dome is a three-dimensional structure composed of
subchondral bone and its overlying cartilage that articulates with the weight
bearing portion of the femoral head.
Multiple studies have concluded that the single most important factor
affecting long-term outcome in both operatively and nonoperatively treated
acetabular fractures is maintenance of a concentric reduction of the
femoral head beneath an intact or anatomically reconstructed dome.
The dome, or roof, can be seen on the anteroposterior and Judet views of the
pelvis, but the subchondral bone shown on each of these views is only 2 to 3 mm
wide and represents only that small portion of the actual articular weight bearing
surface that is tangential to the x-ray beam.
Matta et al. developed a system for roughly quantifying the acetabular
dome after fracture, which they called the roof arc measurements.
8/2/2019 Acetabulum Set 5 p 81
6/25
These measurements involve determination ofhow much of the roof remains
intact on each of the three standard radiographic views: anteroposterior,
obturator oblique, and iliac oblique.
The medial roof arc is measured on the anteroposterior view by drawing a
vertical line through the roof of the acetabulum to its geometric center.
A second line is then drawn through the point where the fracture line
intersects the roofof the acetabulum and again to the geometric center of
the acetabulum.
The angle thus formed represents the medial roof arc
The anterior and posterior roof arcs are similarly determined on the
obturator oblique and iliac oblique views, respectively
Although these are rough quantitations, they are useful in the assessment of
fractures of the posterior or anterior column, transverse fractures, T-type
fractures, and associated anterior column and posterior hemitransverse
fractures; they have limited usefulness for evaluation of both-column fractures
and fractures involving the posterior wall.
According to Matta et al., ifany of the roof arc measurements in a displaced
fracture are less than 45 degrees, operative treatment should be
considered.
Computed tomography is invaluable in the treatment of acetabular fractures.
Axial cuts must be taken with thin (3-mm) intervals and corresponding slice
thicknesses.
The entire pelvis generally is included to avoid missing a portion of the fracture,
and comparison to the opposite hip is performed routinely.
In general, the transverse fracture lines and fractures of the anterior and
posterior walls are in the sagittal plane, paralleling the quadrilateral surface
when they are viewed on axial CT images
Anterior and posterior column fractures usually extend through the
quadrilateral surface and into the obturator foramen with a more coronalorientation; variant fracture types, however, may not follow these generalities.
Olson and Matta showed that CT scans can give the same information about the
acetabular dome as the roof arc measurements on the anteroposterior and oblique
radiographs.
8/2/2019 Acetabulum Set 5 p 81
7/25
Axial CT scans showing the superior 10 mm of the acetabular roof to be intact
corresponded to radiographic roof arc measurements of 45 degrees.
They also found that fracture of the cotyloid fossa did not jeopardize stability of
the femoral head under the dome if the fossa extended to within 10 mm of the
apex of the roof and the articular surface was intact.
Three-dimensional CT reconstructions of a fracture have become sophisticated
and can be projected in many different views with subtraction of the femoral head
that show unique features of the various fracture patterns..
CLASSIFICATION
The classification of acetabular fractures described by Letournel and Judet is the
most widely used classification system.
They divided acetabular fractures into two basic groups: simple fracture types
and the more complex associated fracture types.
Simple fracture types are isolated fractures ofone wall or column along
with transverse fractures; this type includes fractures of the:
1. Posterior Wall,
2. Posterior Column,
3. Anterior Wall, Or Anterior Column
4. Transverse Fractures.
The associated fracture types have more complex fracture geometries and
include:
1. T-Type Fractures,
2. Combined Fractures of the Posterior Column and Wall,
3. Combined Transverse and Posterior Wall Fractures,
4. Anterior Column Fractures with a Hemitransverse Posterior Fracture
5. Both-Column Fractures.
8/2/2019 Acetabulum Set 5 p 81
8/25
Letournel and Judet classification of acetabular fractures.
A. Posterior wall fracture.
B. Posterior column fracture.
C. Anterior wall fracture.
D. Anterior column fracture.
E. Transverse fracture.
F. Posterior column and posterior wall fracture.
G. Transverse and posterior wall fracture.
H.T-shaped fracture.
I. Anterior column and posterior hemitransverse fracture.
J. Complete both-column fracture
Although several of the associated fracture types involve both columns of the
acetabulum, the designation both-column fracture in this classification denotes
8/2/2019 Acetabulum Set 5 p 81
9/25
that none of the articular fracture fragments of the acetabulum maintain
bony continuity with the axial skeleton: a fracture line divides the ilium, so
the sacroiliac joint is not connected to any articular segment.
The spur sign, shown on the obturator oblique view, is pathognomonic of a both-
column fracture.
It represents the remaining portion of the ilium still attached to the sacrum and is
seen projected lateral to the medially displaced acetabulum
The AO group has developed an alphanumeric classification system for
acetabular fractures based on the severity of the fracture:
Type A fractures include fractures of a single wall or column;
Type B fractures involve both anterior and posterior columns (transverse, or T-
type, fractures);
Type C fractures involve both anterior and posterior columns, but all
articular segments, including the roof, are detached from the remaining
segment of intact ilium
Type C fractures are those designated both-column fractures in the Letournel and
Judet classification.
Each type has subtypes 1, 2, and 3 (e.g., A1, A2, or A3), depending on the
characteristics of the fracture.
TREATMENT
Initial Treatment
8/2/2019 Acetabulum Set 5 p 81
10/25
Acetabular fractures generally are caused by high-energy trauma, and associated
injuries are frequent.
Treatment of the entire patient should follow accepted Advanced Trauma Life
Support (ATLS) protocol, with orthopaedic management of the acetabular
fracture appropriately integrated into the treatment plan.
In general, operative treatment of an acetabular fracture should not be
performed as an emergency except when it is part ofopen fracture
management or is performed for a fracture associated with an irreducible
dislocation of the hip.
In the latter case, urgent open reduction of the hip dislocation and treatment
of the associated fracture are required to prevent the complications of
osteonecrosis and ongoing cartilaginous damage to the femoral head.
Closed reduction of hip dislocations should be performed with sedation in theemergency department or with general anesthesia and fluoroscopy.
The patient then can be placed in skeletal traction to maintain reduction and
possibly slight distraction of the hip while the other acute injuries are treated and
radiographic studies of the pelvis are obtained.
The older term central fracture-dislocation of the hip was previously used to
describe any acetabular fracture with medial subluxation of the femoral
head.
Although this terminology has been replaced with more descriptive fracture
classification systems, a true central fracture-dislocation, with the femoral
head completely dislocated medially into the pelvis, is an unusual injury that
requires urgent treatment
The femoral head can be locked between the fracture fragments, making
reduction extremely difficult.
Closed reduction with general anesthesia and fluoroscopic assistance should be
attempted.
After reduction, the femoral head is extremely unstable and will easily redisplace
into the pelvis if skeletal traction is not maintained
INDICATIONS FOR NONOPERATIVE TREATMENT
1) Nondisplaced and Minimally Displaced Fractures
8/2/2019 Acetabulum Set 5 p 81
11/25
Fractures that traverse the weight bearing dome but are displaced less
than 2 mm can be treated with nonweight bearing for 6 to 12 weeks,
depending on the fracture characteristics.
Radiographs should be obtained immediately after the patient is first mobilized
and periodically thereafter to ensure that no displacement has occurred.
2) Fractures with Significant Displacement but in which the region of the
joint involved is judged to be Unimportant Prognostically
This determination is made with the roof arc measurements described by Matta
and Olson as 45 degrees for each roof arc: medial, anterior, and posterior.
Most authors agree that displaced fractures through the weight bearing
dome should be treated with operative reduction and internal fixation,
regardless of how they may line up in traction.
These fractures have a tendency to displace, leading to inferior results.
One exception to this rule is an extremely comminuted both-column
fracture that attains secondary congruence.
In reality, very few fractures are treated definitively by traction to maintain a
reduction of the acetabular dome.
Posterior wall fractures associated with posterior fracture-dislocations of
the hip require separate consideration and are evaluated after closed reduction.
Larger posterior wall fragments lead to posterior hip instability andrequire fixation.
Posterior wall fractures involving more than 50% of the posterior wall consistently
led to posterior hip instability.
Traditionally, any patient for whom nonoperative treatment of a small
posterior wall fracture is being considered should have a clinical evaluation
of hip stability with flexion to 90 degrees with the patient sedated or
under general anesthesia.
We should perform stress views under fluoroscopy when patients are consideredfor nonoperative treatment of smaller posterior wall fractures.
As described by Tornetta, view the pelvis in the obturator oblique view,
flexing the hip to 90 degrees with enough posteriorly directed pressure to rock the
pelvis.
8/2/2019 Acetabulum Set 5 p 81
12/25
Spot fluoroscopic views obtained during performance of this maneuver are
scrutinized to assess subluxation.
Stable hips are treated similar to pure dislocations of the hip, with
mobilization on crutches with range of motion restrictions and progressive weight
bearing during approximately 2 weeks.
3) Secondary Congruence in Displaced Both-Column Fractures
A both-column fracture, by definition, has all its fragmentsfree to move
independent of the remaining ilium.
Frequently, comminuted both-column fracture fragments assume a
position ofarticular secondary congruency around the femoral head,
even though the femoral head is displaced medially and there may be gaps
between the fracture fragments.
The concept ofsecondary congruence was described by Letournel, and
closed treatment of these fractures has yielded reasonable and occasionally
exceptional results.
The concept applies only to this specific subset of fractures and cannot be
applied to other fracture types.
4) Medical contraindications to surgery
In patients with multiple trauma, medical contraindications from multisystem
injury are common, even in previously healthy patients.
On occasion,severity of the medical condition mandates that operative
intervention be delayed.
On occasion, severe head trauma with a tenuous, evolving spectrum of injury
may preclude a surgical procedure.
5) Local Soft-Tissue Problems, such as Infection, Wounds, and Soft-Tissue
Lesions from Blunt Trauma
An open wound in the anticipated surgical field is a contraindication, as is
systemic infection.
The Morel-Lavalle lesion is a localized area of subcutaneous fat necrosis
over the lateral aspect of the hip caused by the same trauma that causes the
acetabular fracture.
8/2/2019 Acetabulum Set 5 p 81
13/25
The size and extent of this lesion are variable, and operating through it has
been associated with a higher rate of postoperative infection.
Alternatively, some fractures can be treated through the ilioinguinal approach,
thus avoiding the affected area.
The presence of a significant Morel-Lavalle lesion can be suspected by
hypermobility of the skin and subcutaneous tissue in the affected area from
the shear-type separation of the subcutaneous tissue from the underlying
fascia lata.
The presence of a suprapubic catheter generally is considered a
contraindication to acetabular openreduction and internal fixation by the
ilioinguinal approach.
The best method of avoiding this situation is to discuss with the urologist the
possibility ofavoiding suprapubic drainage of the bladder with possibleprimary repair of the bladder rupture and Foley catheter drainage.
6) Elderly Patients with Osteoporotic Bone in Whom Open Reduction May
Not Be Feasible
Only rare comminuted fractures in elderly, osteopenic patients cannot be treated
by standard open reduction and internal fixation.
The options for these patients include mobilization without fixation,
percutaneous fixation with mobilization, and primary total hip
arthroplasty.
INDICATIONS FOR OPERATIVE TREATMENT
1) Fracture Characteristics
An acetabular fracture with 2 mm or more of displacement in the dome of the
acetabulum as defined by any roof arc measurementsof less than 45
degrees is an indication for operative intervention, as is any subluxation of
the femoral head from a displaced acetabular fracture noted on any of the
three standard radiographic views.
Also, operative treatment should be considered for posterior wall fractureswith more than 50% involvement of the articular surface
Posterior wall fractures involving less than 50% of the wall may be unstable
and are assessed clinically by flexing the hip to 90 degrees with the patient
sedated or anesthetized as well as by stress testing ofequivocal cases under
anesthesia with fluoroscopy.
8/2/2019 Acetabulum Set 5 p 81
14/25
2) Incarcerated Fragments in the Acetabulum after Closed Reduction of a
Hip Dislocation
Fragments noted on CT scan to be lodged between the articular surfaces of the
femoral head and the acetabulum warrant excision.
3) Prevention of Nonunion and Retention of Sufficient Bone Stock for Later
Reconstructive Surgery
The last indication is debatable and should be applied only in cases of extreme
deformity because total hip arthroplasty after failed open reduction and internal
fixation of an acetabular fracture may be more difficult than hip arthroplasty after
nonoperative management.
Timing of Surgery
Most authors advocate waiting 2 or 3 days after injury before performing
acetabular surgery to allow the patient to be adequately stabilized and to allowpelvic bleeding to subside.
Ideally, operative reduction and internal fixation of acetabular fractures
should be performed within 5 to 7 days of injury.
Anatomical reduction becomes more difficult after that time because
hematoma organization, soft-tissue contracture, and subsequent early
callus formation hinder the process of fracture reduction, especially if the more
limited Kocher-Langenbeck or ilioinguinal exposure is used.
After a delay of more than 2 to 3 weeks, an extensile exposure may benecessary to obtain adequate reduction.
Choice of Surgical Approach
Some fracture patterns are routinely reduced through an anterior ilioinguinal
approach, whereas the posterior Kocher-Langenbeck approach is more
appropriate for others.
With transverse fractures, the choice of an anterior or posterior approach is
determined by which exposure allows access to the side of the fracture with
maximal displacement.
Osteotomy of the trochanter also can aid exposure oftransverse fractures
or supraacetabular extension of fractures of the posterior column and wall.
This osteotomy does not seem to affect the vascularity of the femoral head and
has a high rate of union.
8/2/2019 Acetabulum Set 5 p 81
15/25
Siebenrock et al. described the trochanteric flip osteotomy, leaving the vastus
lateralis attached to the trochanteric fragment, similar to a trochanteric slide
osteotomy.
More complicated fractures may require one of the extensile approaches, such as
the extended iliofemoral approach described by Letournel and Judet, thetriradiate approach of Mears and Rubash, or the T-approach described by
Reinert et al.
If an extensile exposure is used, Bosse et al. recommended confirmation of the
patency of the superior gluteal artery with angiography because this may be the
only vascular pedicle supplying the abductor muscles.
Treatment of Specific Fracture Patterns
8/2/2019 Acetabulum Set 5 p 81
16/25
A, Multifragmented posterior wall fracture with intraarticular comminution. B,
Posterior column fracture with lag screw reaching anterior column. C, Transverse
fracture with lag screw reaching anterior column. D, Associated transverse and
posterior wall fracture. E, Associated T-type acetabular fracture. Lag screws are
inserted into both anterior and posterior columns. F, Anterior column fracture.
Several lag screws are placed between inner and outer tables of innominate bone. G,
Associated anterior column and posterior hemitransverse fracture. Screws insertedfrom pelvic brim must reach distal to fracture line and engage in posterior column
8/2/2019 Acetabulum Set 5 p 81
17/25
H, Both-column fracture operated on through ilioinguinal approach. Screws inserted
from pelvic brim reach posterior column. I, Both-column fracture. Internal fixation is
performed through extended iliofemoral approach. Two very long screws are inserted
into anterior column and reach superior pubic ramus
POSTERIOR WALL FRACTURES
The most common fracture treated by the average orthopaedist is the posterior
wall fracture.
These fractures are treated through a Kocher-Langenbeck approach with the
patient positioned either prone or in the lateral decubitus position on a
fracture table.
To avoid osteonecrosis of the posterior wall, the posterior wall fragments
must not be detached from the posterior capsule during exposure.
If the fracture extends superiorly into the dome, a trochanteric osteotomymay be performed to allow additional exposure.
The hip is distracted to clear any incarcerated fragments before reduction of
the wall fragments.
A close inspection is made for marginal impaction of articular fragments into
the intact posterior column.
8/2/2019 Acetabulum Set 5 p 81
18/25
Impacted segments are elevated and bone grafted.
After reduction of the wall fragments, provisional fixation with Kirschner
wires can be used while definitive fixation is performed with lag screws and a
contoured reconstruction plate placed from the ischium, over the
retroacetabular surface onto the lateral ilium.
The use ofspring plates has been advocated to improve stability in comminuted
fractures.
These are made out ofone-third tubular plates by cutting or breaking the
plate through the last screw hole and bending down the remaining end as tines,
which are used to capture bone fragments that cannot be easily fixed with
screws.
The spring plate is slightly overcontoured so that when the reconstruction
plate is applied over the spring plate, the captured fragments are heldfirmly in position.
Osteonecrosis of the femoral head as a result of associated hip dislocation,
marginal impaction, multiple fracture fragments, and osteochondral injuries of the
femoral head all adversely affect the out-come of these fractures.
Intraarticular screw placement must be avoided & Intraoperative fluoroscopy in
multiple views should be used to ensure that all screws are extraarticular.
Posterior wall fracture fixed with contoured 3.5-mm pelvic reconstruction plate.
Posterior wall acetabular fracture treated with spring plate and associated contoured
pelvic reconstruction plate.
POSTERIOR COLUMN FRACTURES
Posterior column fractures are relatively uncommon and, if significantly
displaced, require operative reduction and internal fixation.
The Kocher-Langenbeck approach is used routinely.
8/2/2019 Acetabulum Set 5 p 81
19/25
Rotational deformity in addition to displacement must be corrected by placement
of a Schanz screw in the ischium to control rotation while the fracture is
reduced with a reduction clamp.
Typical fixation is with a lag screw combined with a contoured
reconstruction plate along the posterior column.
Posterior column fracture of acetabulum
ANTERIOR WALL AND ANTERIOR COLUMN FRACTURES
Isolated anterior wall fractures are uncommon and sometimes associated with
anterior hip dislocation.
Fractures requiring surgery are fixed through an ilioinguinal or iliofemoral
approach.
Anterior column fractures are approached similarly, with fixation by a contoured
plate along the pelvic brim
At the level of the iliopectineal eminence, the medial wall of the acetabulum
is thin, and screws generally should not be placed in this region.
Anterior column fractures that exit higher through the iliac wing require
fixation along the iliac crest as well.
8/2/2019 Acetabulum Set 5 p 81
20/25
Fixation of low anterior column fracture with contoured plate along pelvic brim.
TRANSVERSE FRACTURES
These fractures, although apparently simple, present a spectrum of
difficulty.
Transtectal fractures, or fractures that occur above the cotyloid fossa,
have the worst prognosis, and accurate reduction is essential.
Juxtatectal fractures, those that occur at thejunction of the cotyloid
fossa with the articular surface, also usually require reduction, whereasinfratectal fractures frequently can be treated nonoperatively.
Reduction most often is through a posterior approach with the patient
positioned prone.
A small Jungbluth clamp is used to reduce the fracture while rotation is
controlled by a Schanz screw in the ischium.
The intraarticular reduction can be assessed directly by distracting the limb in
traction and by palpating the reduction of the quadrilateral surface through
the greater sciatic notch.
Posterior fixation typically is with a buttress plate along the posterior
column with anterior fixation, by use of a 3.5-mm lag screw placed into the
anterior column from a position above the acetabulum.
Care must be taken with placement of the anterior lag screw because of the
proximity ofthe iliac vessels.
8/2/2019 Acetabulum Set 5 p 81
21/25
From the ilioinguinal approach, reduction can be performed by a variety of
methods.
We frequently use plate reduction to close the fracture gap; a large
spiked reduction clamp placed on the quadrilateral surface and the lateral
surface of the ilium in the region of the anterior inferior spine controls medialdisplacement and rotation of the caudad fragment.
Typical fixation is a contoured plate along the pelvic brim with lag screws
directed down the posterior column
On occasion, extensile or combined approaches are necessary for more
complex transverse fractures
POSTERIOR COLUMN FRACTURE WITH ASSOCIATED POSTERIOR WALL
FRACTURE
A Kocher-Langenbeck approach is used, with or without a trochanteric osteotomy.
The column fracture is reduced first, and a short reconstruction plate is
placed posteriorly along the posterior edge of the column.
A separate plate is used for the wall fragment.
When the wall fragment is small, spring plates can be used instead of a
separate wall plate.
Posterior column and posterior wall acetabular fracture fixed with two plates. First
reconstructs posterior column, and second reconstruction plate (supplemental spring
plate) fixes posterior wall fragments
TRANSVERSE FRACTURE WITH ASSOCIATED POSTERIOR WALL FRACTURE
8/2/2019 Acetabulum Set 5 p 81
22/25
This common fracture usually is treated through the Kocher-Langenbeck
approach with the patient prone.
The intraarticular portion of the transverse fracture can be seen through the
defect created by the retraction of the posterior wall fragment.
Reduction of the transverse fracture can be difficult through a Kocher-Langenbeck
approach, particularly when there is impaction of a portion of the dome
An extensile approach rarely may be preferable with comminution of the dome.
Typical fixation is performed by fixing the transverse component with lag
screws into the anterior column while plating the posterior wall, thus further
stabilizing the posterior portion of the transverse fracture.
Transverse posterior wall acetabular fracture fixed through Kocher-Langenbeck
approach with additional trochanteric osteotomy
T-TYPE FRACTURES
These fractures usually can be treated with the patient prone through a
Kocher-Langenbeck approach.
The anterior column fracture line can be reduced through the sciatic notch
after reduction of the posterior column portion or reduced first with displacement
of the posterior column, facilitating clamp placement.
The anterior column is fixed with screws placed down the anterior columnfrom a position above the acetabulum; the posterior column portion can be
fixed with a lag screw and a reconstruction plate.
These fractures can occasionally be treated through an ilioinguinal approach
with a contoured plate placed along the pelvic brim and lag screws
extending into the posterior column.
8/2/2019 Acetabulum Set 5 p 81
23/25
Ifboth the anterior and posterior components of the fracture are
significantly displaced, extensile or combined approaches may be required to
obtain a reduction.
On occasion, with T-type fractures as well as other associated fracture types, a
separate medial fragment is present.
If it is proximal enough to affect stability, a spring plate bent at a 100- to
110-degree angle can be placed under an anterior column plate to maintain
reduction of this fragment.
Another method of fixing this fragment is to place a plate along the quadrilateral
surface through a split in the linea alba (Stoppa approach).
ANTERIOR COLUMNPOSTERIOR HEMITRANSVERSE FRACTURES
These fractures frequently have minimal displacement of the hemitransverse
component and can be treated through the ilioinguinal approach with typical
fixation of the anterior column fracture and separate lag screws from the iliac
fossa adjacent to the pelvic brim extending down the posterior column.
Fractures with significant posterior displacement or intraarticular
comminution with or without impaction may require combined or extensile
approaches.
BOTH-COLUMN FRACTURES
These fractures are sometimes described as T-type fractures that have their
transverse component above the dome of the acetabulum.
They have varying degrees of comminution and can be extremely complex
and difficult to treat.
Many both-column fractures can be treated through an anterior ilioinguinal
approach but a posterior or extensile exposure is required for involvement of
the sacroiliac joint, a significant posterior wall fracture, or intraarticular
comminution that requires reduction under direct vision.
In general, reduction is begun from the most proximal portion of the fracture and
proceeds toward the joint.
Each small fragment must be anatomically reduced because small malreductions
in the ilium above the fracture become magnified at the level of the joint.
Fixation is as varied as the fracture patterns and the approaches used.
8/2/2019 Acetabulum Set 5 p 81
24/25
POSTOPERATIVE CARE
Postoperatively, closed suction drainage is used, antibiotic therapy is continued
for 48 to 72 hours, and passive motion of the hip is begun on the second or third
day.
Touch-down ambulation with crutches usually is allowed by the second to
fourth day and progresses gradually, depending on other injuries.
This minimal weight bearing status is continued for approximately 8 weeks in
patients with simple fractures and 12 weeks in most others.
COMPLICATIONS
1) Mortality - Overall mortality rates after acetabular fractures range from 0% to
2.5%.
2) Osteonecrosis - Itoccurs more frequently after fractures associated withposterior dislocation & is radiographically apparentwithin 2 years of
injury in most patients. Letournel's reported rate of osteonecrosis after
posterior dislocation was 7.5%. Osteonecrosis of the posterior wall can be
caused by the injury or by excessive fracture site exposure because the only
vascular supply of these fragments is the injured posterior capsule of the
hip.
3) Infection - Infections are reported to occur in 1% to 5% of patients and may
destroy the hip joint. Certain factors are thought to increase the risk of
infection, including the presence of a suprapubic catheter in ilioinguinal
approaches and the Morel-Lavalle lesion in Kocher-Langenbeckandextensile approaches. Obesity has been shown to increase the rate of multiple
complications including infection.
4) Sciatic nerve palsies as a result of the initial injury occur in approximately 10%
to 15% of patients with acetabular fractures.Sciatic nerve injury as a
result of surgery occurs in 2% to 6% of patients and is more often associated
with posterior fracture patterns treated through the Kocher-Langenbeck
and extensile exposures. The peroneal component of the sciatic nerve was
more often involved than the tibial component and that the tibial component
had a greater chance of recovery; complete peroneal palsies had the
worst prognosis. Functional recovery has been shown in approximately 65% of
patients, and function may improve up to 3 years after injury.
5) Heterotopic ossification occurs after most extensile approaches, with
moderate-to-severe heterotopic ossification occurring in 14% to 50% of patients
when no prophylaxis is used; it occurs after the Kocher-Langenbeck
approach in approximately 25% of patients in whom no prophylaxis is used
8/2/2019 Acetabulum Set 5 p 81
25/25
.Heterotopic ossification is rare after the ilioinguinal approach unless the external
surface of the ilium is stripped. The effectiveness and choice of prophylactic
measures to prevent heterotopic ossification remain controversial. Currently, for
most patients treated with the Kocher-Langenbeck approach, use indomethacin
(25 mg three times a day for 4 to 6 weeks) or radiation therapy with a one-
time dose of 700 cGy in patients in whom indomethacin is contraindicated.
6) Thromboembolic complications can be devastating; the reported risk of
pulmonary embolism ranges from 2% to 6%. Deep vein thrombosis has been
reported to occur in 8% to 61% of patients with acetabular fractures. Current
protocol involves the use of subcutaneous heparin or enoxaparin as well as
intermittent compression boots while patients are awaiting surgery. Obtain a
preoperative screening duplex Doppler scan in any patient in whom the injury is
more than 4 days old. Use Greenfield vena cava filters in patients with
abnormalities on duplex scans and also occasionally use them in high-risk groups,
including patients older than 60 years, patients with contraindications to
anticoagulation, and patients in whom morbid obesity, malignant disease, or a
history of prior deep vein thrombosis is a factor. Postoperatively, anticoagulation
with enoxaparin followed by warfarin is continued for 6 to 12 weeks unless it is
medically contraindicated.
Total Hip Arthroplasty as Treatment for Acetabular Fracture
Acetabular fractures with extremely poor prognoses can be treated with
primary total hip arthroplasty, using adjunctive fixation of the acetabular
fracture with plates or cables and multiple screw fixation of the cup.
Examples include a neglected comminuted, incongruous, both-column fracture ,late presenting unreduced posterior fracture-dislocation of the hip with severe
marginal impaction and femoral head erosion
One concern with this technique is that the cementless acetabular component
could fail to be incorporated adequately in the healing acetabular bed.
Extensile approaches should be avoided to minimize the risk of infection