Abstract
Adaptive remodeling of soft fibrous tissues under cyclic tensile forces was investigated. Patellar tendons of rat’s knee were harvested and mounted on apparatuses for mechanical stimuli. They were transplanted into the subcutaneous tissues and experienced mechanical stimuli of cyclic tensile forces (1N, 1Hz). Then the tendons were retrieved and their mechanical properties were evaluated with a tensile tester. Four experimental groups were examined in which loading conditions were (1) three times a day (2700 cycles a day) throughout 4 weeks, (2) twice a week (1800 cycles a week) throughout 4 weeks, (3) load-free throughout 4 weeks, or (4) control. Comparing to control group, the tendons in load-free conditions were very weak and shown statistically significant decrease in maximum load, strength and tangent modulus. Contrarily, the tendons in frequent loadings (three times a day) nearly maintained their mechanical properties. Thus the present study clearly elucidated the fact that cyclic tensile forces have significant effects on the mechanical properties of transplanted fibrous tissues.
