Strains and Sprains

Although bones can sometimes be fractured with acute sports injuries, the most commonly injured structures are the muscles, tendons, and ligaments. Tendons attach muscles to bones, and ligaments attach one bone to another.
An acute twisting or overextension of a joint can lead to tears of muscles and tendons, called “strains,” and tears of ligaments result in “sprains.” These tears range from mild to severe. In mild injuries, just a few fibers are torn or stretched. Severe injuries, where there is a tear through the full thickness of the structure, are most often considered unstable injuries and frequently require surgical intervention. The intervertebral disc, a ligament between the vertebrae of the spine that works as a shock absorber, can also be torn, resulting in a disc bulge and/or herniation.
Ankle sprains most often involve tears of one or more of the ligaments along the outside of the ankle. Knee ligaments, including the larger external supportive ligaments and the smaller internal stabilizing ligaments, can also be torn. The cartilage on the back of the patella (knee-cap) can also become eroded from overuse, leading to a condition termed chondromalacia patella.