Pronation of the foot with many overuse injuries in running including medial tibial stress syndrome, or shin splints, and knee pain Hintermann states, “Individuals with injuries typically have pronation movement that is about two to four degrees greater than that of those with no injuries.” He adds however, that between 40% and 50% of runners who overpronate do not have overuse injuries. This suggests that although pronation may have an effect on certain injuries, it is not the only factor influencing their development. The design principles of foot orthoses are founded on knowledge of the functional anatomy of the foot. Pronation of the foot
Ulnar collateral ligament injury of the elbow injury. During the cocking phase of pitching, the shoulder is horizontally abducted, externally rotated and the elbow is flexed. There is slight stress on the UCL in this position but it increases when the shoulder is further externally rotated. The greater the stress the more the UCL is stretched causing strain. During the overhead throwing motion, valgus stress on the medial elbow occurs during arm cocking and acceleration. The initiation of valgus stress occurs at the conclusion of the arm-cocking phase. In the transitional moment from arm cocking to arm acceleration, the shoulder vigorously rotates internally, the forearm is in