Sprain

A sprain is a soft tissue injury of the ligaments within a joint, often caused by a sudden movement abruptly forcing the joint to exceed its functional range of motion. Ligaments are tough, inelastic fibers made of collagen that connect two or more bones to form a joint and are important for joint stability and proprioception, which is the body's sense of limb position and movement. Sprains may be mild (first degree), moderate (second degree), or severe (third degree), with the latter two classes involving some degree of tearing of the ligament. Sprains can occur at any joint but most commonly occur in the ankle, knee, or wrist. An equivalent injury to a muscle or tendon is known as a strain. The majority of sprains are mild, causing minor swelling and bruising that can be resolved with conservative treatment, typically summarized as RICE: rest, ice, compression, elevation. However, severe sprains involve complete tears, ruptures, or avulsion fractures, often leading to joint instability, severe pain, and decreased functional ability. These sprains require surgical fixation, prolonged immobilization, and physical therapy. Pain Swelling Bruising or hematoma caused by broken blood vessels within the injured ligament Joint instability Difficulty with bearing weight Decreased functional ability or range of motion of the injured joint Ligament rupture may cause a cracking or popping sound at the time of injury Knowing the signs and symptoms of a sprain can be helpful in differentiating the injury from a strain or simple fracture. Strains typically present with pain, cramping, muscle spasm, and muscle weakness, and fractures typically present with bone tenderness, especially when bearing weight. Acute sprains typically occur when the joint is abruptly forced beyond its functional range of motion, often in the setting of trauma or sports injuries. The most common cause of sprains in general is repetitive movements (overuse). Ligaments are collagen fibers that connect bones together, providing passive stabilization to a joint.