What happens to ligaments that are immobilized for several weeks?

Ligaments that are immobilized for several weeks typically experience a decrease in tensile strength. This is due to a combination of factors related to the lack of mechanical loading, which is crucial for maintaining the structural integrity of the ligament. When a ligament is immobilized, the absence of stress and strain disrupts the normal physiological processes that promote the synthesis of collagen, the main protein that provides ligaments with their strength and flexibility. Consequently, the collagen fibers may become disorganized or undergo alterations that lead to reduced tensile strength.

In addition, immobilization can result in changes to the cellular environment within the ligament, including increased fibroblast apoptosis and decreased production of the extracellular matrix. This diminishes the structural quality of the ligament over time, making it weaker and more susceptible to injury once mobility is restored. Understanding this physiological response is critical for athletic trainers and therapists, as it highlights the importance of gradual reintroduction of movement and loading to rehabilitate ligaments effectively after periods of immobilization.