8.1.1 Principal Indications

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  Fractures of the acetabulum (anterior wall, anterior column, transverse fractures, combined fractures, two-column fractures)

  
  
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  Pelvic ring fractures with sacroiliac joint rupture, fractures of the ala of the ilium

  
  
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  Tumors

  
  
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  Osteomyelitis

8.1.2 Positioning and Incision

The patient is placed in the supine position on a standard or extension table if indicated. If intraoperative three-dimensional radiographs or navigation are planned, a carbon table should be used. The leg on the affected side is draped to allow free movement. The anterior superior iliac spine and iliac crest are marked.

The approach consists of three windows, which, by sequential retraction of the soft tissues, provide good exposure of the inside of the ala of the ilium, the quadrilateral surface, and the superior pubic ramus as far as the symphysis ( Fig. 8.1 ).

To open the first window, which is also used for anterior stabilization of sacroiliac instability, the incision is made from the posterior portion of the iliac crest as far as the anterior superior iliac spine. For full ilioinguinal access, the incision is continued as far as the symphysis. The tendinous attachment of the external oblique fascia is now divided on the iliac crest just lateral to the anterior superior iliac spine ( Fig. 8.2 ). The iliac fossa is exposed subperiosteally from the internal surface of the pelvis as far as the linea terminalis and anterior sacroiliac ligaments ( Fig. 8.3 ). The sacroiliac joint and lateral parts of the sacrum can now be exposed; the lumbosacral trunk runs approximately 15–20 mm medial to the sacroiliac joint directly on the surface of the sacrum and should be spared during dissection. The risk of damaging the lumbosacral trunk can be minimized by strictly subperiosteal dissection.

Dissection of the second window starts at the anterior superior iliac spine by opening the fascia of the external oblique muscle, with exposure of the spermatic cord or uterine ligament, which is snared together with the ilioinguinal nerve ( Fig. 8.4 ). The posterior wall of the inguinal canal is now opened with division of the common origin of the internal oblique, transversus abdominis, and transversalis fascia from the inguinal ligament. A strip of inguinal ligament approximately 1 cm wide should remain to facilitate subsequent reapproximation and anatomical closure of the inguinal canal. The lateral femoral cutaneous nerve, which must be spared, is exposed laterally. The vascular space is then carefully dissected. The iliopectineal arch is exposed by bluntly retracting the vessels medially and the iliopsoas and femoral nerve laterally, and it can be divided sharply as far as its attachment to the iliopubic eminence. The iliopsoas is now snared ( Fig. 8.5 ).

The third window is located between the snared vessels and the lateral border of rectus abdominis. Adequate exposure of the medial pubic ramus is achieved by careful dissection and retraction of rectus abdominis. There may be anastomoses between the external iliac or inferior epigastric artery and the obturator artery (“corona mortis”), which should be ligated prior to bone exposure.

If dissection of the symphysis is required, this is done by splitting the linea alba, if possible without dividing the attachment of the rectus abdominis ( Fig. 8.6 ).

According to von Lanz and Wachsmuth, the obturator artery arises from the inferior epigastric artery in 22–28 %, from the external iliac artery in 1–2 %, from the internal iliac artery in 45 %, and from the inferior gluteal artery in 10 % of cases.

8.1.3 Anatomical Site

( Fig. 8.7 )

The following anatomical structures lie between the split aponeurosis of the external oblique muscle and the anterior pelvic bone as seen from lateral to medial: iliacus, the lateral femoral cutaneous nerve, the femoral nerve, psoas major, psoas minor, the genitofemoral nerve, the iliopectineal arch, the femoral vessels, and the spermatic cord with the ilioinguinal nerve. Located behind the symphysis, which is revealed at the medial angle of the wound, is the bladder. Craniad dissection of the peritoneum exposes the fifth lumbar vertebra, the promontory, and the iliac vessels and testicular vessels.

8.1.4 Wound Closure

Anatomical wound closure is required to avoid a postoperative hernia. Rectus abdominis is reattached with subsequent reconstruction of the posterior wall of the inguinal canal using an absorbable continuous suture ( Fig. 8.8 ). Adequate patency of the internal inguinal ring is essential. The iliopectineal arch does not have to be reconstructed. Finally, the aponeurosis of the external oblique is reattached, and the wound is closed ( Fig. 8.9 ).

8.1.5 Dangers

Frequent complications of this approach are bleeding from the nutrient channels, hemorrhage from the corona mortis, injury to the lateral femoral cutaneous nerve, and hernia if the inguinal region is not reconstructed in full. However, many other complications are possible because of the extensive dissection. If the operation is prolonged and the vessels are manipulated extensively, medical prophylaxis for thrombosis warrants particular attention.

8.2.1 Principal Indications

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  Acetabular fractures involving the posterior column, posterior wall and transverse fractures, in combination with the anterior approach in the case of two-column fractures

  
  
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  Removal of intra-articular bone fragments

8.2.2 Positioning and Incision

The operation can be performed with the patient placed in the prone or lateral decubitus position. In both cases, the leg is draped to allow free movement. The skin incision begins slightly caudal to the palpable greater trochanter, follows the femoral axis cranially, and then curves posteriorly above the trochanter, aiming for the posterior superior iliac crest. After the fascia lata has been exposed, it is split longitudinally somewhat posterior to the trochanter ( Fig. 8.10 ).

Gluteus maximus is split in the line of its fibers until the gluteal neurovascular bundle becomes visible. This must be spared as the inferior gluteal nerve innervates the anterior part of gluteus maximus.

The trochanteric bursa is now excised, and the sciatic nerve is then identified, most easily where it courses over quadratus femoris. The nerve does not have to be snared but must be spared throughout the operation. Tension on the nerve can be reduced by flexing the knee. After identifying the pelvitrochanteric muscles (“short external rotators”), these are divided approximately 1–2 cm from their origin on the trochanter ( Fig. 8.11 ). The medial circumflex femoral artery must always be spared. It is located at the superior border of quadratus femoris. The tendon ends are snared and dissected from the hip joint capsule to the sciatic notch ( Fig. 8.12 ). The posterior joint capsule is now incised, and the femoral head is exposed. To improve visualization, a Schanz screw can be inserted in the femoral neck through the innominate tubercle to allow iatrogenic dislocation.