Is needle examination always necessary in evaluation of carpal tunnel syndrome?

Abstract

To investigate whether needle evaluation added any important clinical information to normal nerve conduction studies in the evaluation of carpal tunnel syndromes. Retrospective review of electromyography (EMG) done with the referring diagnosis of possible carpal tunnel syndrome. Outpatients seen for EMG evaluation at one university hospital by a single electromyographer. Consecutive sample of possible carpal tunnel syndrome patients. None. We determined whether needle examination was abnormal when nerve conduction studies were normal. In patients in whom only carpal tunnel syndrome was suspected, normal nerve conduction studies predicted that EMG would be normal 89.8% of the time (p = .0494). Testing based on a larger sample size might increase the predictive value. There may be a subpopulation of patients referred for carpal tunnel syndrome who may be adequately evaluated by nerve conduction studies alone. Additional studies will help evaluate whether this is so.