Electrical studies as a prognostic factor in the surgical treatment of carpal tunnel syndrome.

We attempted to determine if a prognostic value could be associated with preoperative electrodiagnostic testing in patients with carpal tunnel syndrome. Three groups of patients were included in the study of 151 workers whose symptoms were thought to be causally related to their jobs. A clinical diagnosis was made without electrical testing in 26 of the 151 patients. Normal electrical test values were present in 50 of the 125 patients tested, and abnormal values were noted in 75 patients. Pinch, power, and static grasp function were recorded monthly. Similar recovery patterns after operation were seen between the groups and within each group. Return to work time correlated well with measured functional recovery to preoperative levels, but some workers returned to their jobs before they had regained full function. Electrodiagnostic test results did not provide significant data for prediction of functional recovery or re-employment after carpal tunnel release.