Length change patterns of the medial ligaments of the knee

The medial structures of the knee such as the superficial medial collateral ligament (sMCL), deep medial collateral ligament (dMCL) and posteromedial capsule (PMC) are the most frequently injured tissues and a lot of research has been conducted. However, the length change patterns of these tissues have not been fully reported, such as isometry. Isometry has an important role when positioning grafts to reconstruct ruptured ligaments, in order to reproduce normal knee motion. The purpose of this study was to investigate the length change patterns of sMCL, dMCL and PMC. 10 cadaveric knees were tested to measure the patterns using linear variable displacement transducers between 0° and 100° (in 10° increments) of flexion. The result shows the desirable length patterns which depend on their anterior or posterior orientation as the knee flexes.