Because of the unusual and somewhat vulnerable design of the human shoulder, there are a variety of shoulder injuries that are unfortunately fairly common. One of those injuries is dislocation. Dislocation occurs when the ball at the top of the bone in the upper arm pops out of the socket. It can happen if the shoulder is twisted or pulled very hard.
Another common shoulder injury is called a separation. A shoulder separation occurs when the ligaments between the collarbone and the shoulder blade are torn. The cause of this injury is usually a blow to the shoulder or a fall onto an outstretched hand.
Two other common shoulder problems include tendinitis and bursitis. These conditions can occur alone or simultaneously. In tendinitis of the shoulder, the tendons become red, and swollen from being pinched by another part of the shoulder. This inflammation can be extremely uncomfortable.
Bursitis occurs when the bursa, the small fluid-filled sacs that cushion the shoulder joint, become inflamed. Bursitis can be caused by disease, such as rheumatoid arthritis. Bursitis is also sometimes caused by athletic activities that overuse the shoulder or by jobs that involve reaching overhead on a regular basis.
Yet another fairly common shoulder injury is called a rotator cuff tear. Rotator cuff tendons can become inflamed because of overuse, and sometimes they can be injured from a fall on an outstretched hand or due to some athletic activities. Jobs involving repetitive overhead motion can also damage the rotator cuff. Aging causes tendons to wear down, which can also lead to a tear. Some tears are not painful, while others can be very painful.
Finally, one or more of the bones in the shoulder can suffer a fracture, which is a crack through part or all of a bone. In the shoulder, a fracture usually involves the collarbone or upper arm bone. Fractures are often caused by a fall or blow to the shoulder.