The metatarsal-phalangeal-joint is what causes turf toe.

These are the most common ligaments involved in ankle sprains. 

A herniated disc could threaten the career of a offenive lineman in football.

The hamstring muscle is responsible for allowing your leg to move at your knee joint.

The collarbone is also knows as the clavicle and attaches your sternum to your shoulder blade. It also protects the muscles and blood supply in the area.