Collagen gel contraction as a measure of fibroblast function in carpal tunnel syndrome.

Noninflammatory subsynovial connective tissue (SSCT) fibrosis with nerve compression is a prominent feature of carpal tunnel syndrome (CTS). Studies have shown that SSCT matrix synthesis and material property changes in CTS are associated with increased activity of transforming growth factor (TGF)-β1. The aim of this study were to (1) investigate the ability of SSCT fibroblasts from CTS patients and unaffected individuals to contract a collagen gel ring and (2) determine how the addition of TGF-β1 affects this ability. SSCT fibroblasts from three normal cadavers and three age-matched female patients who had undergone surgery for CTS were used. Results showed patient cell-seeded gels had a significantly higher contraction rate (p < 0.001) than control cells, and fully contracted gel rings possessed a significantly higher tensile strength (p = 0.003) and stiffness (p < 0.001). Furthermore, TGF-β1 significantly intensified contraction rate (p < 0.001), tensile strength (p < 0.001), and stiffness (p < 0.001). In conclusion, SSCT cells from normal donors and CTS patients contract collagen gel rings differently, and this ability is affected by TGF-β1 treatment. This cell-seeded collagen gel model may be useful for developing new methods of stopping or eliminating the effect of TGF-β1 on the SSCT fibroblasts and surrounding matrix, which might aid in the identification of medical treatment for CTS.