Sciatic neuropathies

Abstract

Most reports on sciatic neuropathies record wartime experience. We have reviewed the causes of sciatic nerve lesions in an urban peacetime setting. All the patients were seen in the electromyographic laboratory of a large general hospital for evaluation of leg weakness. Each was examined by a neurologist and underwent nerve conduction and electromyographic studies. Thirty nine electrophysiologically confirmed sciatic neuropathies were detected in 34 patients. Five patients developed sciatic neuropathies after an episode of coma resulting from an overdose of drugs or alcohol or both. Two patients had prolonged coma after a head injury and their bilateral neuropathies resulted from being bedridden for many weeks. One patient developed bilateral sciatic nerve compression after an eight hour operation in the sitting position. One patient worked for a long time in a cramped position with his buttock against a sharp edge. Hip fracture-dislocations (10 patients)-The typical injury was a hip fracture including the posterior acetabulum. The commonest cause was a motor vehicle accident. Five patients had had total hip replacements and one a Chiari type pelvic osteotomy. Direct trauma (four patients)-These patients had suffered direct injuries to the thighs, but only one had a fractured femur. Miscellaneous (four patients)-One patient had endometriosis at the sciatic notch, compressing the sciatic and inferior gluteal nerves. Another developed compression at this site from a haematoma resulting from anti-coagulation treatment for a pulmonary embolus after a hip replacement. In only one patient (with bilateral sciatic neuropathies) were the lesions due to injections. One patient had a sciatic neuropathy as part of a mononeuritis multiplex syndrome of unknown aetiology.