acetabula fractures
TRANSCRIPT
Acetabular Fractures
Joshua Landau, MD
David Seidman, MD
11/23/04
Overview
Radiographs Classification Treatment Options Surgical Approaches
Radiographic Evaluation
From the lateral, acetabulum is inverted Y Anterior column Posterior column
Sciatic notch through obturator and inferior pubic ramus
AP
6 Lines Iliopectineal Ilioischial Posterior wall Anterior wall Dome Teardrop
Radiographs
AP
6 Lines Iliopectineal Ilioischial Posterior wall Anterior wall Dome Teardrop
Oblique
Iliac Oblique
Posterior column Anterior wall
Iliac Oblique
Posterior column Anterior wall
Iliac Oblique
Posterior column Anterior wall
Oblique
Obturator
Anterior column Posterior Wall
Obturator Oblique
The Dome
The Dome
Weight Bearing Dome:Roof arc angle
Vertical line through the rotational center of acetabulum
Angled line through the fracture
Mata: <45 deg on any view
Recently: anterior <25 Medial <45 Posterior <70
Top of the dome distally for 1 cm on CT
Classification: Letournel and Judet
Classification: Special Notes
Both column essentially a T
type occurring proximal to the joint
No portion of the articular surface is attached to axial skeleton
SPUR SIGN Division of
both columns ABOVE the acetabulum
Secondary congruence
AP view
Obturator oblique view
Iliac oblique view
Representative CT cuts of the fracture, demonstrating that approximately 50 percent of the posterior wall is affected.
Posterior Wall
Beware posterior hip dislocation
Sometimes completely unstable
Traction to maintain reduction until fixation
Osteochondral fx common: require fixation/reduction if in weight bearing portion
Biomechanics
Weight bearing portion: Primarily posterior and
superior Hip stable
<20% of posterior wall Hip unstable
>40% of posterior wall
Posterior Wall Fracture
Blood supply is from capsule: do not detach
Flip over leaving capsule if possible
Anterior column + posterior hemitransverse vs. T type
Reducing anterior column usually reduces posterior column, post capsule is not usually disrupted
In contrast, in the T type, reducing the anterior does not reduce the posterior and the post capsule is disrupted
T type
T type
T type
Must involve obturator foramen
Both Column
Both Column
Treatment options
Nonoperative Traction NWB Indicated if
displacement < 2mm
Operative ORIF ORIF w/ THA
Absolute indication is hip instability / subluxation out of traction
Operative vs. Non-op
Classic Articles Rowe and Lowell: non-
op is preferred Judet et. al: 90% good
result if anatomic reduction, 74% good result overall
Current Literature Rowe and Lowell
2 groups of fractures High energy forces,
incongruous joint Operative
management is better Low energy, minimal
displacement Non-op management
is satisfactory
Surgical Considerations
Timing Surgery should be
completed within 7 d results deteriorate
after 3 weeks
Approaches Iliofemoral Ilioinguinal Kocher-Langenbach Triradiate Extended Iliofemoral Combined
Iliofemoral
Anterior column or anterior wall fractures w/ displacement cephalad to hip joint
Lag screws into anterior column Plate only fits on crest of ilium, not on
pelvic brim
Ilioinguinal
For anterior fractures where access to entire anterior column
Can be used for both column fx only if posterior piece is large and intact
Don’t see articular surface, only fx lines in pelvis
Commonly sacrifice lateral cutaneous nerve of the thigh
Divide external oblique from inguinal ring to asis, expose spermatic cord/round ligament
Ligate inferior epigastric vessels
Ilioinguinal
Complications: Femoral nerve injury LFCN Thrombosis in femoral
vessels
Ilioinguinal
Sling 1: iliopsoas Sling 2: external iliac
artery and vein (aka femoral sheath)
Sling 3: spermatic cord
Kocher-Langenbach
Isolated posterior wall or posterior column injuries only
Exposure limited superiorly by superior gluteal vessels and greater trochanter
High incidence of HO and sciatic injury
May consider troch osteotomy
Complications: Sciatic nerve 2-10% Damage to femoral
head blood supply via medial femoral circumflex a.
Triradiate
Both column fractures ASIS to top of sciatic
notch is exposed Expose TFL, divide
TFL and G. max Remove greater troch Capsulorrhaphy and
joint exposure
Extended iliofemoral
Exposes Outer table of ilium Superior dome Posterior column Anterior column to
iliopubic eminence Provides exposure to
bone above sciatic notch
Highest risk for HO Also risk for superior gluteal artery
injury leading to muscle necrosis
Approach by fracture type
Kocher-Langenbach Posterior column
Prone is best Weight of leg in lateral
position causes rotation of posterior column
Posterior wall Lateral is OK
Posterior column + posterior wall
Prone is best
Anterior column + posterior hemitransverse Ilioinguinal approach
usually adequate
Transverse fxs Depends on location
of displacement T type is most difficult
Approach by fracture type
Both Column If posterior column is a
single large fragment, then ilioinguinal approach is preferred
If posterior column is not reduced, then add Kocher-Langenbach
If significant posterior wall fracture, choose extensile or combined approach
Reduction
Traction Fracture table Direct pull on femoral
neck Corkscrew into femoral
neck T handled bone hook
on greater troch
External distractors
5 or 6 mm Schanz threaded pin through the ischial tuberosity as joystick for T type or posterior column fxs
Farabeuf clamps on screws inserted on either side of fx
Reduction
Cerclage wires may help through the greater or lesser sciatic notch
Fixation
Interfrag lag screws 3.5 mm cortical
screws, even in cancellous bone
No tap necessary except in dense bone of sciatic butress
3.5 mm recon plate contoured
Outcomes
THA after ORIF of acetabulum does better than THA after unreduced acetabulum fx
Complications
Thromboembolism: 60% of cases
HO Use XRT or indomethacin
peri/post op for prophylaxis w/ Kocher-Langenbach approach
Neurologic injury AVN
18% of posterior fracture patterns
Post-traumatic DJD Abductor weakness Intra-articular
hardware