Extraspinal bone and soft-tissue tumors as a cause of sciatica. Clinical diagnosis and recommendations: analysis of 32 cases.

STUDY DESIGN Between 1982 and 1997, the authors treated 32 patients with sciatica who subsequently were found to have a tumor along the extraspinal course of the sciatic nerve. SUMMARY OF BACKGROUND DATA Extraspinal compression of the sciatic nerve by a tumor is a rare cause of sciatica. Signs and symptoms overlap those of the more common causes of sciatica (i.e., herniated disc and spinal stenosis). OBJECTIVE To characterize the unique clinical presentation of these patients and to formulate guidelines that may lead to early diagnosis. METHODS All pertinent clinical data and studies were reviewed retrospectively, and standard demographic data were collected for analysis. RESULTS These patients typically sought treatment for an insidious onset of sciatic pain that was constant, progressive, and unresponsive to change in position or bed rest. The mean time to final diagnosis was 11.9 months (median, 6 months). Seventeen patients were able to locate their pain to a specific point along the extraspinal course of the sciatic pain, and a mass was noted in 13 patients. Eighteen of these tumors were in the pelvis, 10 in the thigh, and 4 in the popliteal fossa and calf. CONCLUSIONS A high index of clinical suspicion is the key to early diagnosis of bone or soft-tissue tumors as a cause of sciatica; special attention should be given to pain pattern, physical examination of the entire course of the sciatic nerve, and selection of proper imaging studies. Routine anteroposterior plain radiography of the pelvis as part of the initial imaging screening process is recommended.