Tendons and ligaments
High injury potential
The tendons connect muscles to bones and transmit the forces to the skeletal system. They consist of collagenous connective tissue fibres that are slightly sinuous when not under tension and thus enable a damping of the transmission of forces to the bone.
The tendon sheaths are tubes filled with lubricating fluid through which the tendons glide. They are found wherever tendons run at angle or pass over bony prominences. This reduces the friction between the tendons and the surrounding tissues when they move.
Joints are held securely by ligaments. Ligaments are connective tissue connections between two bones that help stabilise the joint. In general, they are relatively inelastic, which means they become lax or rupture completely if they are overstretched.
Ligament injuries of the knee joint are common sports injuries. The cruciate ligaments are usually overstretched or ruptured by direct or indirect trauma, for example, when rotation movement of the knee joint is abruptly stopped.
Ligamentous injuries of the ankle joint are also often seen during sporting activities. Ruptures of the lateral ligaments and capsular injuries in the ankle joint occur most often when the ankle is bent on landing.