The Effect of Immobilization on Collagen Turnover in Connective Tissue: A Biochemical-Biomechanical Correlation

TLDR

The study proposes that the observed stiffness loss after immobilization is caused by changes in ligament substance rather than tissue atrophy. Nine weeks of knee immobilization reduced mechanical properties and stiffness of the lateral collateral ligament, while collagen mass in the medial collateral ligament and patellar tendon remained unchanged but their turnover increased.

Abstract

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.