An analysis of the flexor synovium in idiopathic carpal tunnel syndrome: report of 625 cases.

This study was undertaken to determine the presence or absence of tenosynovitis in persons with idiopathic carpal tunnel syndrome. Eight hundred thirty-five consecutive operations for carpal tunnel syndrome were retrospectively reviewed, and 625 cases of idiopathic carpal tunnel syndrome were identified. Of these 96% (601) had a synovial tissue histologic diagnosis of benign fibrous tissue without inflammation, 4% (23) showed chronic inflammation, and 0.2% (1) revealed evidence of acute inflammation. We believe that tenosynovitis is not a part of the pathophysiologic process in chronic idiopathic carpal tunnel syndrome. Further histologic analysis of the flexor synovium for pathologic changes other than inflammation is needed.