The aim of our study was to examine both age and gender-related alterations in collagen expression of the transverse carpal ligament (TCL) in patients with idiopathic carpal tunnel syndrome (CTS).
Resected TCLs were collected from 10 patients undergoing open carpal tunnel decompression. These were randomly divided equally into two groups of five patients, with equal numbers of men (average age 49.6) and women (average age 57.4). Histological staining [Hematoxylin & eosin and Picrosirius red (PSR)] and Western blot analysis were performed on the resected tissue.
Data from the histological analysis showed a 73% increase in fibroblast cell densities in the TCL specimens from the CTS patients. The PSR staining-polarization microscopic and immunoblot analysis data shows that men have significantly increased collagen I and decreased collagen III (P ˂ 0.05) compared to women. An age-related decline was observed in the expression of collagen I in both sexes, and the ratio of collagens III to I was significantly increased (P ˂ 0.05) in women compared to men. The major component of the TCL in both sexes was found to be Collagen type VI. Levels of collagens II, V and X were also elevated to lesser extents.
Our data enhances the understanding of collagen alterations in the transverse carpal ligament in CTS. Collagens I and III are significantly elevated, especially in males, while other collagen isoforms, II, V, VI, and X, are also up-regulated. Moreover, there appears to be a general decrease in the up-regulation of collagen levels as a function of advancing age.