A sprain is an injury that damages a ligament. A ligament is a firm, fibrous band of tissue. It connects two bones across a joint. There are ligaments crossing all of the joints in the body.

Grade 1 and 2 sprains are less severe. The internal structure of the ligament is damaged, but the ligament remains intact. Grade 3 sprains are more severe. They include complete tears of the ligament. Grade 3 sprains are sometimes called torn or ruptured ligaments.

Sprain: Grade 2
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A sprain occurs when a force pushes the bones of a joint apart. If the force is intense enough, the ligament holding the joint together has to give.