SCIATIC NEUROPATHY - CLINICAL AND PROGNOSTIC FEATURES IN 73 PATIENTS

We examined the clinical features of patients with sciatic neuropathy and the factors that influence prognosis. Of 92 consecutive patients r eferred for EMG evaluation of sciatic neuropathy, 73 fulfilled strict inclusion and exclusion criteria and had adequate clinical and electro physiologic information. The etiologies included hip arthroplasty (21. 9%), acute external compression (13.7%), infarction (9.6%), gunshot wo und (9.6%), hip fracture/dislocation (9.6%), femur fracture (4.1%), co ntusion (4.1%), and uncertain (16.4%). We used life table analysis to determine outcome and to identify prognostic factors in patients with acute or subacute onset. Moderate or better recovery (improvement to g rade 2 or by two of six clinical grades) occurred in most patients (30 % by 1 year, 50% by 2 years, 75% by 3 years). A subgroup experienced e xcellent improvement (by three of six grades, or to grade 2! less freq uently (33% by 2 and 3 years). Of the nine factors tested, two predict ed an earlier or better recovery: a recordable compound muscle action potential of the extensor digitorum brevis (p < 0.025), and an initial absence of paralysis of muscles controlling ankle plantar flexion and dorsiflexion (p < 0.05). Thus, good but incomplete recovery occurs ov er 2 to 3 years in most patients with sciatic neuropathy, particularly in those without severe motor axonal loss.