The effect of anterior knee joint loading on hamstrings muscle stiffness

The biomechanical function of ligaments is well known. However, ligaments also play an important sensory role through their ability to communicate with muscles. This study aims to better understand the relationship between internal passive structures of the knee joint and the surrounding musculature. The effect that loading the knee joint as well as the effect that changing the moment on the knee joint has on hamstrings muscle stiffness is examined. The occurrence of a possible muscle spindle response is investigated. The timing of a muscle spindle reflex as a result of a muscle stretch is analyzed as a possible explanation for the change in hamstrings muscle stiffness. The results of this study demonstrate that anterior loading the knee joint leads to an increase in hamstrings muscle stiffness. An increase in hamstrings muscle stiffness is also shown to possibly be associated with a faster muscle spindle response. This study highlights the important sensory function of ligaments within the knee.