histologic findings in idiopathic carpal tunnel syndrome: report of 209 cases

Background- Carpal tunnel syndrome is a common disease with multifactorial etiology. The study of histologic findings of the disease can help us identify its etiologic factor(s). The purpose of this study was to determine whether there are any typical or consistent histologic changes in the transverse carpal ligament or flexor tenosynovium, which contribute to idiopathic carpal tunnel syndrome.Methods- Two hundred and nine consecutive operations for carpal tunnel syndrome between December 1995 and December 2000 were reviewed retrospectively. All patients had no history of systemic disease and no anatomic anomaly. Using hematoxylin-eosin and Congo red dyes, the sections were stained and reviewed histopathologically.Results- A total of 176 (84%) patients had benign fibrous tissue, 31 (15%) showed amyloid deposits and 2 (1%) showed mild vascular proliferation.Conclusion- In idiopathic carpal tunnel syndrome, the ligament and tenosynovium often showed normal histology and there were no typical changes. We believe that inflammation is not a part of the pathophysiologic process in idiopathic carpal tunnel syndrome.