Less invasive posterior surgical approach for hip joint replacement--complications and limitations.

BACKGROUND: We attempted to analyse the difficulties and risk of complications associated with total hip replacement using a limited posterior approach and standard instrumentation.

MATERIAL AND METHODS: A series of 85 consecutive cases (47 females and 38 males; age range 22-87 years; mean age: 65.6 +/- 10.4) of total hip replacement using a modified Gibson approach were analyzed prospectively. Bilateral surgery was performed in 7 patients. There were 44 non-cemented arthroplasties. Body mass index varied from 22 to 36 (body weight 78-104 kg) and the length of the operative wound varied from 6.5 to 14 cm (mean 9.8 +/- 1.3 cm). The wound was 14 centimeters long in six subjects with a BMI of 35-36. The procedure was performed in a lateral decubitus position using an appropriately limited posterior approach. After careful coagulation of blood vessels surrounding the base of the femoral head posteriorly, the obturator and gemelli tendons and the posterior part of the joint capsule were cut through as close to the femoral attachment (T) as possible. This made it possible to dislocate the joint posteriorly. Further stages of the procedure were performed in a typical manner, with special attention paid to the preservation of the tendon of the piriformis muscle. Continuity of the muscle was re-examined following the reposition of the artificial joint.

RESULTS: Two injuries to the piriform tendon were observed. Persistent bleeding from vessels surrounding the femoral neck base occurred in 5 patients while in four others there was transient paresis of the peroneal muscles and dorsal extensors of the ipsilateral foot, probably caused by extension of the sciatic nerve. There was one oblique fracture of the proximal femoral shaft. We did not observe significant errors in postoperative joint geometry. Mean intraoperative blood loss was 400 ml. We did not note postoperative dislocations or infections.

CONCLUSIONS: On the basis of our observations of a series of 85 patients, minimizing the extent of the posterior surgical approach for hip joint replacement seems an attractive alternative to the classical extensive technique. Our material reveals a relatively high incidence of transient paresis of the peroneal part of the sciatic nerve. The introduction of appropriate instrumentation and the accumulation of experience will certainly decrease the risk of extension of the sciatic nerve in the operative wound.