LATE SUPERIOR GLUTEAL AND SCIATIC-NERVE P ALSY FOLLOWING SURGICAL-TREATMENT OF POSTERIOR FRACTURE - DISLOCATION OF THE HIP

Four month after surgical treatment of posterior fracture dislocation of the hip a 44-year-old male developed progressive pain and weakness of the left leg. Neurological examination showed severe superior glute al and sciatic nerve palsy, and electrophysiological studies presented abnormal spontaneous activity, motor units and interference pattern o f gluteus medius, biceps femoris, tibialis anterior and gastrocnemius muscle. Roentgenogram and CT scan revealed ectopic ossifications betwe en acetabulum and trochanter major, and 3-dimensional reconstruction c onfirmed compression of the sciatic nerve. After surgical decompressio n and neurolysis, neurological deficit and electrophysiological abnorm alities improved. Early sciatic nerve palsy after posterior dislocatio n and dislocation fracture of the hip are a common complication. Accor ding to their etiology they are distinguished in traumatic caused by d irect and indirect mechanisms, and postoperative during surgical proce dure. Although secondary ectopic bone formation is frequent, late scia tic nerve palsies due to compression are rare complications requiring surgical exploration and neurolysis.