Medline Plus indicates that ligaments exist to connect bones to other bones, and they usually to keep their arrangement stable. Ligaments are found throughout the body, especially in areas with many joints, such as the hands and feet. EhealthMD advises that ligaments may tear during athletic activities or simply during the course of everyday life, and some damaged ligaments must be repaired surgically to restore full function to the affected joint.
The anterior cruciate ligament, found at the front of the human knee, is a ligament that athletes frequently injure. Often, it becomes injured when the knee becomes hyperextended or turns inward too far. EhealthMD explains that when this ligament becomes injured, repair often necessitates replacing the entire ligament.
According to Wikipedia, ligaments are composed of collagenous fibers. When they break, they do not normally heal without intervention. Doctors and researchers are beginning to use artificial materials to replace torn, stretched or disconnected ligaments.
Scientists do not understand the purpose of some ligaments. According to CBS News, despite knowing that it existed, the purpose of the anterolateral ligament was not understood until 2013. After reviewing 41 different knee joints, a group of Belgian surgeons determined that the anterolateral ligament plays an important role in stabilizing the knee.