Fibroblast responses to variation in soft tissue mobilization pressure

UNLABELLED: Augmented soft tissue mobilization therapy (ASTM), a newly developed massage therapy, has been successfully used in the treatment of chronic tendinitis patients. We theorized that the ASTM technique promotes healing through a controlled application of microtrauma. PURPOSE: The purpose of this study was to determine morphologic changes in the rat Achilles tendon after enzyme-induced injury with collagenase and subsequent pressure variations in ASTM therapy. METHODS: Thirty male white rats were randomly assigned to one of five groups with six animals per group: tendinitis (A), tendinitis plus light ASTM (B), tendinitis plus medium ASTM (C), tendinitis plus extreme ASTM (D), and control with surgery only (E). ASTM was performed for 3 min, for a total of six treatment sessions. The Achilles tendons of each group were harvested 1 wk after the last ASTM treatment. Fibroblast numbers were assessed by light microscopy. An electron microscope was used to observe enlargement of fibroblasts. RESULTS: Statistical analysis of the number of fibroblasts present indicated a significant difference (P<0.00) between group D and all other groups. CONCLUSION: The morphological evidence indicated that the application of heavy pressure promoted the healing process to a greater degree than light or moderate pressure.