The effect of immobilization on collagen turnover in connective tissue: a biochemical-biomechanical correlation.

Immobilization of the knee joint for 9 weeks results in a reduction of the mechanical properties in the lateral collateral ligament. Specifically, ligament stiffness is reduced in this tissue. No statistical change in collagen mass was detected for the medial collateral ligament (MCL) or patellar tendon. An increase in collagen turnover (synthesis and degradation) was, however, found in the immobilized medial collateral ligament and patellar tendon. It is thus proposed that stiffness reduction is due to a change in the ligament substance itself, rather than a result of tissue atrophy.