Acetabular fracture

fractures of acetabulum- anatmy and orthopedic management

1. Acetabular Fractures,imaging and management Presented by : Harjot Singh Gurudatta Moderator : Dr. Gagan Khanna

2. All three parts of the innominate bone contribute to form the acetabulum. o    Pubis -------- anterosuperior part of the articular surface -------- 1/5 th . o    Ischium ----- posteroinferior part of nonarticular surface -------- 2/5 th . o    Ilium -------- rest of acetabulum -------- 2/5 th corona mortis  At risk over superior pubic ramus A N A T O M Y   Directed laterally, downwards and forwards. lateral inclination of 40 to 48 degrees , anteversion of 18 to 21 degrees  The margin is deficient inferiorly and this deficiency is called the acetabular notch , bridged by the transverse acetabular ligament. The nonarticular roughened floor is called the acetabular / COTYLOID fossa It contains a pad of fat lined by synovial membrane.  A horse-shoe shaped articular surface or lunate surface is seen on the anterior, superior and posterior parts of the acetabulum.(ACETABULAR dome)  It is lined by hyaline cartilage and articulates with the head of femur; the articular cartilage is thickest here.

3. the quadrant of death

4. Normal Anatomy: Letournel – Judet Columns and Walls From the lateral aspect of the pelvis, the innominate osseous structural support of the acetabulum may be conceptualized as a two-columned construct forming an inverted Y. The anterior and posterior walls extend from each respective column and form the cup of the acetabulum. The anterior and posterior columns connect to the axial skeleton through a strut of bone called the sciatic buttress

5. Bony Anatomy Anterior Column Anterior column ( iliopubic component): extends from iliac crest to symphysis pubis and includes the anterior wall of the acetabulum.

6. Bony Anatomy Posterior Column Posterior column ( ilioischial component): extends from superior gluteal notch to ischial tuberosity and includes the posterior wall of the acetabulum

7. When looking at the acetabulum en face , the anterior and posterior columns have the appearance of the Greek letter lambda (λ). The anterior column represents the longer, larger portion, which extends superiorly from the superior pubic ramus into the iliac wing. The posterior column extends superiorly from the ischiopubic ramus as the ischium toward the ilium. The anterior and posterior columns of bone unite to support the acetabulum. In turn, the sciatic buttress extends posteriorly from the anterior and posterior columns to become the articular surface of the sacroiliac joint, which attaches the columns to the axial skeleton. The anterior and posterior walls, which extend from the columns and support the hip joint, are well seen on an axial CT.

8. The anterior and posterior walls, which extend from the columns and support the hip joint, are well seen on an axial CT. Axial section through acetabulum shows anterior ( arrowhead ) and posterior ( arrow ) walls.

9. Acetabular dome: The superior weight-bearing portion of the acetabulum at the junction of the anterior and posterior columns, including contributions from each.

10. Anterior column in white, posterior column in red

11. Like pelvis fractures, these injuries are mainly caused by high-energy trauma secondary to a motor vehicle, motorcycle accident, or fall from a height.

The fracture pattern depends on Position of femoral head at the time of injury, Magnitude of force, &
Age of patient. Mechanism of injury With indirect trauma, (e.g., a ‘dashboard’ injury to the flexed knee) : As the degree of hip flexion increases, the posterior wall is fractured in an increasingly inferior position. Similarly, as the degree of hip flexion decreases, the superior portion of posterior wall is more likely to be involved .

12. Mechanism of injury Direct impact to greater trochanter with: Hip in neutral : transverse acetabular fracture An abducted hip: low transverse fracture, An adducted hip: high transverse fracture. Hip externally rotated and abducted : anterior column injury. Hip internally rotated : posterior column injury.

13. Clinical evaluation Trauma evaluation: with attention to ABCD, depending on the mechanism of injury. Patient factors (age, degree of trauma, presence of associated injuries, & general medical condition) affect treatment decisions as well as prognosis. Neurovascular assessment: Sciatic nerve injury may be present in up to 40% of posterior column disruptions. Femoral nerve involvement with anterior column injury is rare, although compromise of the femoral artery by a fractured anterior column has been described. Presence of associated ipsilateral injuries must be ruled out, with particular attention to the ipsilateral knee in which posterior instability and patellar fractures are common. Soft tissue injuries (e.g., abrasions, contusions, subcutaneous hemorrhage) may provide insight into the mechanism of injury.

14. IMAGING : Radiographic evaluation 5 Pelvic X-rays: AP view 2 Judet views (iliac & obturator oblique views) Inlet and Outlet Pelvis X-rays CT scan

15. Anatomic landmarks in AP view Iliopectineal line (limit of anterior column), Ilioischial line (limit of posterior column), Anterior lip, Posterior lip, Line depicting the superior weight-bearing surface, terminating as the medial teardro p .

16. Taken by rotating the patient into 45° of external rotation by elevating the uninjured side on a wedge. This best demonstrates: Posterior column ( ilioischial line), *Iliac wing, border of sciatic notch * Anterior rim of acetabulum. Iliac oblique radiograph (45-degree external rotation view)

17. This is best for evaluating the anterior column and posterior wall of the acetabulum(iliac wing and spur sign(both colum # seen here) Taken by elevating the affected hip 45° to the horizontal by means of a wedge and directing the beam through the hip joint with a 15° upward tilt. beam is roughly perpendicular to the obturator foramen Obturator oblique radiograph (45-degree internal rotation view)

18. AP pelvis Iliac oblique Obturator oblique AW — anterior wall; AC — anterior column; PC — posterior column; PW — posterior wall; OR — obturator ring.

19. Inlet Pelvis X-ray Best demonstrates ring configuration of pelvis Evaluates for posterior displacement of pelvic ring or opening of pubic symphysis Patient lies supineThe central ray is directed 40° to 60° caudal and enters at the level of the anterior superior iliac spine. This view will demonstrate the pelvic inlet in its entirety. A properly positioned inlet view of the pelvis should demonstrate the superior and inferior ramus of the pubic bones superimposed medially, near superimposition of the superior pubic ramus and ischial ramus, and symmetry of the ischial spines

20. Outlet Pelvis XR The patient is placed supine on the radiographic table with the midsagittal plane aligned to the center of the grid. The central ray is directed 20° to 45° cephalic at the level 2 inches below the symphysis pubis. A properly positioned outlet view will demonstrate the superior and inferior rami of the pubis the superior and inferior rami of the pubis and the ischia, sacroiliac joint and vertical displacement

21. Internal limb = outer wall of obturator canal External limb = middle 1/3 of cotyloid fossa Inferior border = ischiopubic notch Radiographic teardrop composed laterally of most inferior and anterior portion of acetabulum and medially of anterior flat part of quadrilateral surface of iliac bone Teardrop

22. Radiographic evaluation CT scan Provides additional information regarding size & position of column fractures, impacted fractures of acetabular wall, retained bone fragments in the joint, degree of comminution, and sacroiliac joint disruption. Three-dimensional reconstruction allows for digital subtraction of femoral head, with full delineation of the acetabular surface

23. Radiographic evaluation CT scan Before a 3-dimensional CT scan is ordered, the fracture patterns should be drawn on a 3-dimensional model of the pelvis to compare the 3-dimensional reconstructions and to aid Classification If sup glutel artery flap is planned, an angiogrphy should be done to ensure its continuity especially in post. Column #

24. Classification Accurate classification based on radiographs , CT, Associated injuries of acetabular fractures is important for determining the proper surgical treatment. Various classification system Judet-Letournel Harris coupe Comprehensive syetem of classification

25. Classification (Judet-Letournel) Because of the complex acetabular anatomy, various classification schemes have been suggested, but the Judet-Letournel classification system remains the most widely accepted. This classification system subdivides acetabular fractures into Elementary Fracture Types (posterior wall, posterior column, anterior wall, anterior column and transverse) Associated Fracture Types (T-shaped, posterior column and wall, anterior wall or column with posterior hemitransverse , and both column).

26. MC,Ischium + ischiopubic rami Ilioischial line# additional break in the ischiopubic segment Part of dome attached to ilium

27. Classifications

28. Transverse Fracture Types (depending on the orientation of the fracture line relative to the dome or tectum of the acetabulum): Transtectal : through the acetabular dome. Juxtatectal : through the junction of acetabular dome & fossa acetabuli . Infratectal : through the fossa acetabuli . Transtectal fractures are less forgiving and must be reduced anatomically. Transverse fractures are sagittal plane fractures whereas both column fracturesare coronal plane fractures. The femoral head follows the inferior ischiopubic fragment and may dislocate centrally.

29. Othopaedic Review Course January 2010 T-fracture Transverse/post.wall Post.wall/post.column Ant.post.hemitrans. Ass.both.column Associated types

30. Transverse fracture of any type + Vertical fr through the isciopubic fragment The vertical component is best seen on the obturator oblique view. T-shaped fracture

31. The T-shaped fracture is similar to a both-column fracture in that it disrupts the obturator ring. Another similarity is disruption of both the iliopectineal and ilioischial lines. However, the superior extension of the fracture does not involve the iliac wing, which allows differentiation from the both-column fracture. T-shaped fracture In a pure transverse fracture, the anterior and posterior columns may be reduced through a single approach In a T- type fracture, the 2 columns must be reduced separate

32. Both columns are separated from each other and from the axial skeleton, resulting in a ‘ floating ’ acetabulum This is the most complex type of acetabular fracture. A both columns fracture can be considered a ‘ high ’ T-shaped fracture where both columns have been separated from the sciatic buttress. Both-column fracture
(formerly called ‘central acetabular fracture’)

33. Both-column fracture
(formerly called ‘central acetabular fracture’) "Spur-sign" seen on the obturator oblique view The "spur-sign," best seen on the obturator oblique view, is pathognomonic for the both-column fracture. This sign represents posterior displacement of the sciatic buttress of the iliac wing fracture, which essentially disconnects the roof of the acetabulum from the axial skeleton. When this occurs, weight from the torso and upper body can no longer be supported by the acetabulum.

34. Both-column fracture
(formerly called ‘central acetabular fracture’) On radiographs and CT, the spur sign appears as a shard of bone extending posteriorly at the level of the superior acetabulum. Evaluation of sequential CT images shows the fracture, which separates the sciatic buttress from the acetabular roof.

35. 3-D CT scan of a both-column acetabular fracture; obturator oblique view

36. Classification (The Comprehensive Classification of Fractures of the Acetabulum)

37. The Comprehensive Classification of Fractures of the Acetabulum

38. Roof Arc Angle(MATTA) The medial, anterior, & posterior roof arcs are measured on AP, obturator oblique, and iliac oblique views, respectively. The roof arc is formed by the angle between two lines, one drawn vertically through the geometric center of the acetabulum, the other from the fracture line+ roof intersection to the geometric center. Roof arc angles are of limited utility for evaluation of both column fractures and posterior wall fractures . To find the amount of INTACT acetabular roof to decide treatment 1. Medial Roof Arc (AP pelvis) 2. Anterior Roof Arc ( Obturator oblique) 3. Posterior Roof Arc (Iliac oblique)

39. Roof arc measurement

40. Question 1 Classify the following acetabular frx Letournel Acetabular Frx Classification Elementary      Anterior wall Anterior column Posterior wall     Posterior column     Transverse Associated    T-shaped     Anterior wall/column plus posterior hemitransverse     Transverse plus posterior wall     Posterior column plus posterior wall     Both-column

41. Question 2 Classify the following acetabular frx Letournel Acetabular Frx Classification Elementary      Anterior wall Anterior column Posterior wall     Posterior column     Transverse Associated    T-shaped     Anterior wall/column plus posterior hemitransverse     Transverse plus posterior wall     Posterior column plus posterior wall     Both-column

42. MCQ 3 Which two quadrants of the acetabulum are most at risk for injury by screws during fixation of total hip arthroplasty (THA): Anterior-inferior and posterior-superior Anterior-superior and posterior-superior Anterior-superior and anterior-inferior Anterior-superior and posterior-inferior Posterior-superior and posterior inferior

43. Answer 3 Which two quadrants of the acetabulum are most at risk for injury by screws during fixation of total hip arthroplasty (THA): Anterior-inferior and posterior-superior Anterior-superior and posterior-superior Anterior-superior and anterior-inferior Anterior-superior and posterior-inferior Posterior-superior and posterior inferior

44. Explanation The acetabular quadrant system described by Wasielewski and colleagues is useful for determining the location of planned acetabular screw fixation in THA to avoid neurovascular complications. The quadrants are formed by drawing a line from the anterior-superior iliac spine through the center of the acetabulum and bisecting that line at the center of the acetabulum to form four equal quadrants. The line from the anterior-superior iliac spine to the center of the acetabulum serves as the dividing line between anterior and posterior, and the bisecting line as the division between superior and inferior. In cadaver studies, the posterior-superior and posterior-inferior quadrants were shown to have the thickest bone and best potential for obtaining secure fixation with the least risk for injury to vessels. The anterior-superior quadrant (the quadrant of death) and the anterior-inferior quadrant were shown to be the most dangerous quadrants for fixation due to the thin bone and close proximity of the vessels to bone in that region.

45. TO BE CONTINUED

46. Acetabular Fractures,imaging and MANAGEMENT 2 Presented by : Harjot Singh Gurudatta Moderator : Dr. Gagan Khanna

47. TILL NOW PT CAME>>>>>>ABCD>>>>>STABILISATION>>>>>>>>>CLINICAL EXAMINATION >>>>>>>NEUROVASCULAR ASSESSMENT>>>>>>XRAYS 5 VIEWS>>>>>>>CT HIP >>>>>CLASSIFICATION OF ACETABULUM # >>>>>> Presence of associated ipsilateral injuries, with particular attention to the ipsilateral knee in which posterior instability and patellar fractures are common. Soft tissue injuries (e.g., abrasions, contusions, subcutaneous hemorrhage, MORELL LOVELLE LESION) ROOF ARC MEASUREMENTS DONE AS DESCRIBED >>>>>WAIT AND WATCH AND DECIDE FURTHER>>>>>

48. Goal of Treatment The goal of treatment is anatomic restoration of the articular surface , prevent posttraumatic arthritis, Mobilise patient, minimise asso . Compl .

49. Initial Management The patient is usually placed in skeletal traction to allow for initial soft tissue healing, allow associated injuries to be addressed, maintain limb length, & maintain femoral head reduction within the acetabulum.

50. Non-operative treatment(MATTA-MERITT CRITERIA) Indications: Displacement <5mm in the dome, or articular step-off of <2mm (with maintanance of femoral head congruency out of traction, & absence of intraarticular osseous fragments). N.B. If a fracture is displaced <2mm, no matter what the anatomical type, nonoperative treatment should yield good results. No # in CT Subchondral bone with in 10cm of joint. # in non weight bearing dome: Low anterior column fractures Distal anterior column or transverse ( infratectal ) fractures in which femoral head congruency is maintained by the remaining medial buttress.# Low transverse fractures Low T-shaped fractures. Even both column # with sec congruence Maintenance of medial, anterior and posterior roof arcs >45° (indicating fracture stability) Pt , is unfit for surgery

51. Operative treatment Indications Head unstable and/or incongruous joint Guidelines to be correlated to patient factors . Hip dislocation associated with: Posterior wall or column fractures (posterior instability) Major anterior wall fractures (anterior instability) Any fracture with significant size quadrilateral plate fracture (Central instability)

52. Incongruity Displaced dome fractures: surgery is usually necessary to restore the weight-bearing surface. High transverse or T-type fractures These are shearing injuries that are grossly unstable when they involve the superior, weight-bearing dome. Displaced both-column fractures (floating acetabulum): Retained osseous fragments may result in incongruity or an inability to maintain concentric reduction of the femoral head.. Femoral head fractures generally require ORIF to maintain sphericity and congruity. Soft tissue interposition may necessitate operative removal of the interposed tissues. Fractures through the roof or dome

53. Operative treatment Timing Surgery should usually be performed within 2 weeks of injury and usually after 1 week. It requires A well-resuscitated patient. Appropriate radiologic workup. Appropriate understanding of the fracture pattern. Appropriate operative team. Surgical emergencies include: Open acetabular fracture. New-onset sciatic nerve palsy after closed reduction of hip dislocation. Irreducible posterior hip dislocation. Medial dislocation of femoral head against cancellous bone surface of intact ilium

54. Assessment of reduction Assessment of reduction includes: Restoration of pelvic lines. Concentric reduction on all 3 views. The goal of anatomic reduction.

55. Operative treatment Contraindications?/ Relative non operative Operative contraindications local or systemic infection, severe osteoporosis Relative contraindications advanced age, associated medical conditions associated soft tissue and visceral injuries, multiply injured patient not stable for a big acetabular surgery

56. Morel– Lavallé lesion (Skin Degloving Injury A closed degloving injury over the greater trochanter. The subcutaneous tissue is torn away from the underlying fascia, and a significant cavity containing hematoma and liquified fat forms These areas must be drained and debrided before or during definitive fracture surgery to decrease the chance of infection. Advisable to leave this area open through the surgical incision or a separate incision with regular care. Primary excision of the necrotic fat and closure over a drain has not been routinely successful.

57. Infection 6-10% Nerve palsy Sciatic nerve: Kocher- Langenbach approach with prolonged or forceful traction. Femoral nerve: Ilioinguinal approach may result in traction injury to femoral nerve. Rarely, the nerve may be lacerated by an anterior column fracture. Superior gluteal nerve: most vulnerable in the greater sciatic notch. Injury during trauma or surgery may result in paralysis of hip abductors with severe disability. Thromboembolic Complications

58. Complications Heterotopic bone formation Extensile approaches Young patient with muscle split Kocher- Langenbeck Indocin 25mg TID Low Dose Radiation Excision after 15-18 mo : 80% of normal motion if no arthritis Avascular necrosis, arthritis

59. Surgical Approaches Kocher- Langenbeck (Posterior): best access to posterior column (lateral/prone) I lioinguinal (Anterior): best access to anterior column and inner aspect of innominate bone (supine) Extended iliofemoral (Lateral): best simultaneous access to the two columns (lateral) Combined approaches performed concurrently or successively is less desirable No single approach provides ideal exposure of all fracture types. Proper preoperative classification of the fracture configuration is essential to selecting the best surgical approach. Intraoperatively , corkscrew, schanz pin, reduction forceps help to achieve reduction

60. Surgical approaches: FRACTURE TYPE APPROACH ELIMENTARY FRACTURES 1 Posterior wall Kocher-Langenbeck 2 Posterior column Kocher-Langenbeck 3 Anterior wall Ilioinguinal 4 Anterior column Ilioinguinal 5 Transverse Infratectal/Juxtatectal Transtectal Kocher-Langenbeck Extended iliofemoral or Kocher-Langenbeck

61. Surgical Approaches: ASSOCIATED FRACTURES 1 Posterior column + wall Kocher-Langenbeck 2 Anterior + posterior Hemitransverse Ilioinguinal 3 Transverse + posterior wall Infratectal/Juxtatectal Transtectal Kocher-Langenbeck Extended iliofemoral or Kocher-Langenbeck 4 T – shaped Infratectal/Juxtatectal Transtectal Kocher- Langenbeck or combined Extended iliofemoral or combined 5 Associated both column ABC Ilioinguinal .

62. Kocher- Langenbeck Approach

63. Kocher-Langenbeck Approach 1 M. glutaeus maximus 2 M. glutaeus medius 3 M. glutaeus minimus 4 M. piriformis 5 M. gemellus Superior 6 M. obturatorius internus 7 M. gemellus inferior 8 M. quadratus femoris 9 Lig . Sacrotuberale 10, N.,A.,V., glutea inferior 11 N.,A.,V., glutea superior

64. Kocher-Langenbeck Approach Indications Posterior wall fractures Posterior column fractures Posterior column/posterior wall fractures Juxtatectal / infratectal transverse or transverse with posterior wall fractures Some T-type fractures Trochantric osteotomy may be needed for good exposure in high T and posterior wall or post column # extending to supracetabular ilium, for exposing superior dome of acetabulum. acetabular fractures with cranial extension and dome involvement.

65. Entire posterior column Greater & lesser sciatic notches Ischial spine Retroacetabular surface Ischial tuberosity Ischiopubic ramus Areas accessible by Kocher- Langenbeck approach

66. The room is set up such that the x-rays and CT scans are available for viewing during the procedure. The patient is prone on a radiolucent table.

67. The affected extremity is positioned with a distal femoral pin to allow for traction on the table with the hip in slight extension and the knee flexed to relax the sciatic nerve.

68. The incision is midline over the femur, and angles posteriorly at the posterior aspect of the greater trochanter to end slightly superior to the posterior iliac spine. GREATER TROCHANTER

69. The skin incision is brought down to the level of the tensor fascia lata , which is divided in line with the incision. The gluteus maximus fascia is then divided. TENSOR FASCIA LATA GLUTEUS FASCIA

70. The gluteus maximus muscle is identified. GLUTEUS MAXIMUS

71. The maximus muscle is gently separated digitally until the first traversing branches of the nerve are visible.

72. GLUTEAL NERVE BRANCH Dividing the gluteus maximus too far proximally will denervate a significant portion of it.

73. TROCHANTERIC BURSA The trochanteric bursa is divided. GLUTEUS MAXIMUS

74. QUADRATUS FEMORIS View of the deep musculature with the Charnley retractor in place. VASTUS LATERALIS GLUTEUS MEDIUS SHORT EXTERNAL ROTATORS

75. With gentle retraction anteriorly of the gluteus medius, the piriformis tendon comes into view. GLUTEUS MEDIUS PIRIFORMIS

76. OBTURATOR INTERNIS PIRIFORMIS After minimal dissection along the posterior aspect of the short external rotators the obturator internis tendon is identified between the gamelli .

77. TAG SUTURES Both the piriformis and obturator internis are tagged and resected approximately 1cm away from their insertion in the femur. It is helpful before this is performed, to identify the sciatic nerve in an area of healthy tissue , usually at the level of the quadratus femorus .

78. The piriformis and obturator internis are being gently elevated using the sutures. OBTURATOR INTERNIS PIRIFORMIS

79. With the piriformis being held back digitally, the sciatic nerve is visualized running posterior to the obturator internis tendon. OBTURATOR INTERNIS SCIATIC NERVE

80. Knowing that the nerve is safe and can be protected by the obturator internis muscle, a Letournel retractor, or blunt cobra, is placed anteriorly to the obturator internus tendon into the lesser sciatic notch. BLUNT COBRA RETRACTOR OBTURATOR INTERNIS SCIATIC NERVE

81. Once in the lesser sciatic notch, posterior leverage on the retractor allows exposure of the posterior aspect of the acetabulum while protecting the nerve. BLUNT COBRA RETRACTOR OBTURATOR INTERNIS SCIATIC NERVE

82. POSTERIOR ACETABULUM

83. FEMORAL HEAD The femoral head and displaced portion of the posterior wall are easily identified. DISPLACED POSTERIOR WALL

84. After the fracture and fracture bed are cleaned, the posterior wall is reduced and fixed in place with a buttress plate.

85. After the fracture and fracture bed are cleaned, the posterior wall is reduced and fixed in place with a buttress plate. REDUCED FRACTURE

86. Ilioinguinal approach

87. Ilioinguinal Approach 1 M. psoas major 2 M. iliacus 3 Pecten ossis pubis 4 A. iliaca communis 5 A. iliaca interna 6 A. iliaca externa 7 Aa . Vv. Testiculares 8 V. iliaca communis 9 V. iliaca externa 10 N. ilioinguinalis 11 N. genitofemoralis 12 N. obturatorius 13 N. femoralis 14 N. cutaneus femoris lateralis 15 Ductus spermaticus 16 Ductus deferens

88. Ilioinguinal Approach Indications Anterior wall Anterior column Transverse with significant anterior displacement Anterior column/posterior hemitransverse Both-column

89. Setup: The patient is supine on a radiolucent table with skeletal traction holding the affected extremity in slight flexion. A perineal post is used to allow for traction if needed.

90. ASIS ASIS A The incision is drawn out. Figure A shows the location of the incision with respect to the symphysis and ASIS. Figure B shows the patient from the side as one would observe during surgery. The incision is curvilinear towards the posterior aspect of the ilium. The surgery begins by approaching the iliac crest along the area shown in figure B. B SYMPHYSIS

91. Sharp retractors are used to identify the interval between the abductor and abdominal musculature.

92. The iliac crest is indicated by purple lines. The interval between the abdominal and abductor musculature occurs towards the posterior aspect of the iliac crest as the abdominal musculature hangs over the crest (dotted line)

93. The interval is taken with a Bovie down to the iliac crest and the abdominal musculature is reflected anteriorly.

94. After the iliacus is released from the inside of the ilium a large key elevator is used to elevate subperiosteally to the SI joint. ILIUM ILIACUS

95. After this dissection is complete, the posterior aspect of the iliac fossa is packed off with a lap and attention to brought to the anterior portion of the incision.

96. Gelpi retractors are used to retract the skin and soft tissue after the external oblique fascia is identified. EXTERNAL OBLIQUE
FASCIA

97. The external oblique fascia is divided in line with the incision and the fascia is reflected distally. EXTERNAL OBLIQUE FASCIA

98. VAS DEFERENS, SPERMATIC CORD, + ILIOINGUINAL NERVE EXTERNAL OBLIQUE FASCIA INGUINAL LIGAMENT EXTERNAL OBLIQUE FASCIA After this is performed, the vas deferens, spermatic cord, and ilioinguinal nerve are identified and protected with a Penrose drain. Allis c lamps are used to retract the the external oblique fascia.

99. An incision is made in the inguinal ligament, allowing 1 to 2mm of the ligament to reflect medially with the musculature (dotted line).

100. Incision through the inguinal ligament.

101. ASIS As the dissection extends toward the ASIS, one needs to identify the lateral femoral cutaneous nerve, which is immediately under the inguinal ligament. typically located approximately 1cm medial to the ASIS LATERAL FEMORAL
CUTANEOUS NERVE

102. ASIS PSOAS FEMORAL NERVE ILIOPECTINEAL FASCIA EXTERNAL ILIAC VESSELS At this point, the identification of the iliopectineal fascia is performed, allowing for retraction of the exteral iliac vessels and lymphatics medially.

103. ILIOPSOAS MUSCLE FEMORAL NERVE ILIOPECTINEAL FASCIA The psoas muscle and femoral nerve are retracted laterally . The army-navy retractor protects the vasculature while the Allis clamp is holding the iliopectineal fascia. TRUE PELVIS

104. PSOAS FEMORAL NERVE Closeup of the iliopectineal fascia demonstrating the psoas and femoral nerve on the lateral side of the fascia in the false pelvis. The true pelvis is located medial to the iliopecineal fascia over the pelvic brim.

105. PSOAS FEMORAL NERVE Once the iliopectineal fascia is excised, access to the true pelvis is obtained. The medial window of the approach is utilized when buttress plating to the symphyseal body or symphyseal fixation is necessary.

106. LATERAL FEMORAL CUTANEOUS NERVE View from the opposite side of the table demonstrating the lateral window and iliac wing fracture. ILIAC FRACTURE

107. PSOAS LATERAL FEMORAL CUTANEOUS NERVE VESSELS PELVIC BRIM View of the middle window demonstrating the pelvic brim.

108. SI JOINT ILIOPSOAS This figure demonstrates the lateral window and exposure of the anterior column from the iliac crest and S SI joint proximally to the psoas gutter and pelvic brim distally.

109. PELVIC BRIM PSOAS This figure demonstrates the pelvic brim and displacement of the fracture as seen through the middle window. VESSELS

110. SUPERIOR RAMUS FRAGMENT DISPLACED ANTERIOR COLUMN Closeup of the fracture.

111. Extended iliofemoral approach

112. Extended Iliofemoral Approach 1 M. gemellus superior 2 M. obturatorius internus 3 M. gemellus inferior 4 M. piriformis 5 M. quadratus femoris 6 Sehne des M. obturatorius externus 7 Tuber ischiadicum 8 A. circumflexa femoris medialis , tiefer Abzweig 9 N. ischiadicus

113. Extended iliofemoral approach Indications

114. Extended iliofemoral approach Extended iliofemoral approach has the highest incidence of ectopic bone formation (HO) and longest postoperative recovery

115. Other approaches Stoppa approach (supine): Allows access to the medial wall of acetabulum, quadrilateral surface, & sacroiliac joint.corona mortis at risk. Triradiate approach (prone): Alternate exposure to the external aspect of innominate bone, with almost same exposure as iliofemoral but visualization of the posterior part of ilium is not as good

116. Implants Screws – 6.5-mm cancellous lag screws with buttress plate – 4.0-mm cancellous lag screws and 3.5 mm cortical screws (lengths up to 120 mm) – 6.5-mm fully threaded cancellous screws For fixation of the plate to bone, fully threaded cancellous screws are desirable, the 6.5-mm screw for the large reconstruction plate (4.5-mm) and the 3.5-screw for the 3.5-mm reconstruction plate. Cannulated screws may also be helpful.

117. Implants Plates The 3.5-mm and 4.5 mm reconstruction plates for pelvic fixation A 3.5-mm reconstruction plate is the implant of choice for acetabular reconstruction. These plates can be molded in two planes and around the difficult areas such as the ischial tuberosity. Also, precurved 3.5-mm plates are available for anterior column fixation. These plates are fixed with the 3.5-mm cancellous screws. In large individuals, and in pelvic fixation, the 4.5-mm reconstruction plates are also useful, with fixation by the 6.5-mm fully threaded cancellous screws; however, they are rarely used at this time.

118. The plates may be applied to the anterior column from the inner table of the ilium to the symphysis pubis. Plates may also be applied to the posterior column and the superior aspect of the acetabulum. The distal screw should be anchored in the ischial tuberosity. Great care should be taken to ensure that screws in the central portion of the plate do not penetrate the articular cartilage of the acetabulum . In most instances, no screws should be put into that danger area, but if screws are necessary for stable fixation, they should be directed away from the joint. Screws within the joint are a not uncommon cause of chondrolysis. Plates may be nested to buttress small fragments. Plates Sites of Application

119. Internal fixation with lag screw Stable fixation is best achieved by interfragmental compression using lag screws. After provisional fixation of all fractures with K-wires, or cerclage wires, screw fixation of the fractures is essential. The joint must be visualized at all times to ensure that anatomical reduction has been achieved and that no screw penetrates the articular cartilage. After fixation by interfragmental lag screws, plates may be used to neutralize the fracture. Plates may be placed either on the anterior or posterior column, depending on the approach.

120. Closed reduction and percutaneous fixation – proposed for elderly patients & Simple fractures with minimal displacements. No long term results available yet

121. Example Case 48 y/o female Fx dislocation of L acetabulum - displaced Left SI joint injury R non-displaced acetabular fx L:ORIF and Perc SI - FFWB R:Perc - WBAT

122. Postoperative Care Indomethacin or irradiation: for heterotopic ossification prophylaxis. A variety of treatments has been proposed to decrease the amount of heterotopic bone including the use of diphosphonates, radiation and indomethacin. Diphosphonates prevent the mineralisation of osteoid, but this begins again after withdrawal of the drug, and their use has been questioned. There have been several reports of the use of indomethacin after operation for acetabular fractures. Local radiation therapy has also been used after reports of successful results in hip arthroplasty. Chemical prophylaxis, sequential compression devices, and compressive stockings for thromboembolic prophylaxis. Mobilization out of bed is indicated as associated injuries allow. Full weight bearing on the affected extremity should be withheld until radiographic signs of union are present (generally by 8-12 weeks postoperatively).