The anterior transmuscular intrapelvic approach for the treatment of acetabular fractures-a new anterior surgical strategy

Abstract

The anterior ilioinguinal and the posterior Kocher-Langenbeck approach have long been the standard surgical approaches to the acetabulum. The last decade has witnessed the development of so-called intrapelvic approaches for anterior pathologies because they provide better exposure of the quadrilateral plate. Currently, the modified Stoppa approach and the pararectus approach are frequently used by surgeons for the treatment of acetabular fractures. We investigated an even more direct access to the entire anterior column and the quadrilateral plate via the abdominal wall muscles, between the incisions for the ilioinguinal and the pararectus approach.After intensive study of anatomic specimens, a cadaver dissection was performed prior to clinical application. The approach was then used in 20 patients who were assessed retrospectively.Postoperative CT scans showed that, according to the Matta scoring system, the quality of fracture reduction was "anatomical" (≤ 1 mm) in 12 (60%), "imperfect" (2-3 mm) in four (20%), and "poor" (> 3 mm) in four (20%) patients. Numerous minor complications were observed; the majority of these had resolved at the time of discharge.In conclusion, the anterior transmuscular intrapelvic approach (ATI) is a safe and effective alternative to the ilioinguinal and pararectal approaches, and may be regarded as an evolutionary advancement of traditional procedures.

Keywords: Acetabular fracture; Anterior intrapelvic approach.

Fig. 1

Anatomic landmarks and topography of the abdomen. a Two fingerbreadths medial to the ASIS an incision is made slightly curved and towards the pubic symphysis (ASIS anterior superior iliac spine, SY symphysis, NAV naval). b illustration of relation to the underlying bony anatomy. The incision lies directly over the acetabulum.Dissection of subcutaneous fat was followed by exposure and splitting of Scarpa’s fascia and the muscle fascia of the external abdominal oblique muscle in line with the skin incision (Fig. 2a). All three lateral abdominal muscles were divided according to their natural course, while the thin fasciae of the internal oblique and transverse abdominal muscles and the transversalis fascia were cut in line with the skin incision

Fig. 2

a Surgeons view from the left side, Incision (red line) in relation to the anatomic landmarks (ASIS anterior superior iliac spine, SY symphysis). b 3 layers of the abdominal wall can be split in line with the fibers of the muscle (IOM internal oblique muscle, EOM external oblique muscle). c Just below the internus abdominis fascia lies the bundle of the inferior epigastric vessels (IEV) that guide the surgeon to the external iliac vessels. All structures are embedded by fat and lymphatic tissue. Careful dissection reveals the vas deferens (VD) and accompanying deferential vessels (DV). d The genitofemoral nerve (GFN) lies on the iliopsoas muscle (IPM). To expose the iliac wing and the posterior part of the iliopubic line, the IPM can be retracted medially together with the GFN. e careful dissection along the Inferior epigastric vessels will lead to exposure of the external iliac artery and vein (EIA + V). Lateral to this lies the medial window, laterally bordered by IPM, allowing access to the acetabular roof and the iliopectineal line. f lateral Retraction of the IEA + V opens the median window. Mostly a corona mortis (CM) will be visible. Blunt dissection along the quadrilateral plate will reveal the obturator nerve (ON) and accompanying vessels

Fig. 3

Anatomic dissection of relevant structures: a Topography of the pelvic visceral vessels and nerves. The quadrilateral plate is covered by the internal obturator muscle and the tendinous arch of levator ani (TA). b A collinear reduction clamp is placed into the lesser sciatic foramen (LSF) and on top of the acetabular roof to compress an anterior column fracture. The hook is placed close to the ischial spine (IS), a homan retractor can also be positioned here to retract bladder and peritoneum (GSF greater sciatic foramen, SSL sacrospinous ligament, STL sacrotuberal ligament. c The same anatomic specimen: from posteriorly the relation of ischial spine, greater and lesser sciatic notch is displayed. d A soft tissue specimen demonstrates the proximimty of the instrument (hook or homan retractor) to the pudendal canal and the clunium nerve bundle (PC). The inferior gluteal artery (IGA) and the sciatic nerve (SN) take their route distally in line with the sacrotuberal ligament until the vessel crosses the nerve at the level of the ischial tuberosity (IT). (PM piriformis muscle, GM gluteus medius muscle)