Peroneal palsy as a complication of developmental hip dysplasia surgery

Abstract

Nerve injuries are rare complications of surgical management of developmental dysplasia of the hip (DDH). Over-stretching can cause injuries of femoral, sciatic and peroneal nerves. In this report, we present a 6-year-old girl with Tönnis type IV bilateral DDH whose postoperative period was complicated with foot drop due to the breakage of the spica cast. Open reduction and Pemberton pericapsular osteotomies, high femoral osteotomies for derotation and shortening had been performed on both hips of the patient. Patient had been kept in a spica cast for six weeks. At the 6th week follow up visit it was observed that spica cast was broken at the knee. When the cast was removed foot drop was noted on left foot. Electromyoneurography (EMNG) revealed total axonal degeneration of the peroneal nerve at the level of the fibular head. The conservative therapy for 18 months failed to result in any improvement in common peroneal nerve function. Therefore, peroneal nerve decompression, neurolysis and posterior tibial tendon transfer had been performed. At the 4th year follow up visit the patient had active dorsiflexion of the ankle, no need for AFO and the foot was plantigrade and painless. We presented this case report in order to inform the orthopedic surgeons performing DDH surgeries about a possible complication of the spica cast and to emphasis the necessity of good care of the spica cast.