Physical damage to the knee. The knee is the largest joint in the body and subjected to enormous loads during many sports activities. However, it is a relatively unstable joint making it especially vulnerable to injury. Between one-quarter and one-third of all sports injuries involve the knee. The knee is a very complex structure and injuries often affect more than one component making diagnosis notoriously difficult. Many knee injuries are due to overuse (e.g. chondromalacia patellae), but misalignments of muscles and bone in the lower leg also increases the risk of knee injury (see unhappy triad).
Subjects: Sports and Exercise Medicine.