[Internal fixation of acetabular posterior wall fractures].

OBJECTIVE: Open anatomic reduction and stable internal fixation of a posterior wall fracture of the acetabulum by screw and plate osteosynthesis via the Kocher-Langenbeck appoach.

INDICATIONS: Displaced fractures or fracture-dislocations of the posterior wall of the acetabulum in combination with an unstable hip joint, presence of an additional femoral head fracture or intraarticular fragments, reduction inability in fracture-dislocations or deterioration of an additional sciatic nerve injury.

CONTRAINDICATIONS: Poor general condition (due to additional injuries or medical disease). Local soft-tissue damage. Presence of only small bony avulsion fragments of the posterior capsule with hip joint stability.

SURGICAL TECHNIQUE: Open reduction of the posterior wall fracture with stable internal fixation by screw and plate osteosynthesis. Depending on their presence: reduction and fixation of marginal impaction zones.

POSTOPERATIVE MANAGEMENT: Partial weight bearing of the injured side with 15 kg body weight for 6 weeks. Thereafter, pain-dependent weight bearing. In cases of marginal impaction partial weight bearing is extended to 12 weeks.

RESULTS: Between January 1, 1972 and December 31, 2005, 137 patients with fractures of the posterior wall of the acetabulum were treated operatively. A high-velocity trauma was the cause of injury in 91.1% of cases. 94.1% of these patients had an additional hip dislocation, which was reduced within 6 h post injury in 83.7%. A primary sciatic nerve injury was present in 22.2%. Additional injuries to the acetabular cartilage were found in 43%, additional femoral head lesions in 27.4%, and Pipkin fractures in 14.1%. Anatomic joint reconstruction (0-1 mm) was observed in 96.3%, the other five patients had near anatomic reconstructions (2-5 mm). All hip joints were congruent on conventional radiography. The overall complication rate was 11.8%. Osteosynthesis-related complications were seen in 6.7%. 86 patients had follow-up results after a mean of 52 months. A perfect or good functional result (Merle d'Aubigné Score) was observed in 73.3% of cases, a posttraumatic arthrosis of the hip joint was present in 31.4%.