Neurophysiology not required before surgery for typical carpal tunnel syndrome.

Sixty-eight patients with typical carpal tunnel syndrome underwent neurophysiological investigations preoperatively, but these were not assessed until the end of the study. Open carpal tunnel release was performed and the clinical diagnosis of carpal tunnel syndrome was considered as confirmed when there was a prompt resolution of the preoperative symptoms. Sixty-three of the 68 patients responded well to surgery, three had equivocal outcomes and two did not improve, and thus were considered not to have carpal tunnel syndrome. The neurophysiological tests were normal in these two patients, but were also normal in 14 of the 63 patients who improved with carpal tunnel surgery. Preoperative neurophysiology might therefore have led to up to 14 of the 63 cases of carpal tunnel syndrome being turned down for surgery. We conclude that neurophysiological studies contribute little to the diagnosis in typical cases of carpal tunnel syndrome, and are more often confounding than of assistance.