Repetitive stress shoulder injuries are common for baseball players, especially pitchers. The throwing motion puts considerable strain on the soft tissues stabilizing the joint. Pain and clicking sensations are two signs of damage to the joint area. Some injuries may be treated with rest and rehabilitation, while more severe injuries may require surgical repairs and rehabilitation.
Static and Dynamic Stabilizers
The head of the humerus bone fits loosely into the shoulder socket, affording tremendous range of motion and allowing pitchers to throw the ball hard. But the shoulder relies on relatively weak soft tissue to stabilize the joint. The static stabilizers are the labrum, the cartilage ring that surrounds the socket and the shoulder capsule ligaments. The dynamic stabilizers are the muscles surrounding the joint, especially the rotator cuff muscles. The static and dynamic stabilizers work together during the act of throwing.
Labrum Tear
The repeated strain of throwing may cause the labrum to tear away from the shoulder socket. This SLAP -- Superior Labrum Anterior to Posterior -- lesion is a common pitching injury. Symptoms often include the shoulder catching, locking, popping or grinding; a sense of instability in the shoulder joint; decreased range of motion and strength; and pain with overhead activities, according to Dr. Walt Lowe of Houston's Memorial Hermann Sports Medicine Institute. The biceps tendon attaches to the labrum, so tears in this area also can be associated with biceps tendon problems.
Capsule Ligament Tear
This injury often is caused by the subluxation or dislocation of the shoulder, a common injury in football and other contact sports. But the repetitive stress caused by pitching can create instability gradually as well.
Rotator Cuff Tears
Four muscles combine to form a cuff over the upper arm bone. The baseball throwing motion can cause these muscles to tear. "More acute injuries involve an experience of moderate to severe acute pain, a snapping or popping sensation and immediate weakness of the arm," Lowe says.
Little League Shoulder
Bone fractures also can cause shoulder pain, especially in younger players whose growth plates are still open. Fractures may form in the growth plate at the upper end of the humerus. This injury commonly is referred to as "Little League Shoulder."
References
- Sports Injury Info; What is a Labral Tear?
- Dr. Walt Lowe; Knee, Shoulder and Elbow Injury Symptoms
- Sports Injury Bulletin; Shoulder injuries in throwing athletes
- SportsMD; SLAP Tear Superior Labrum Anterior Posterior; Christopher Dodson, May 2011
- Naples Orthopedic Surgery; Pitching arm vulnerable to shoulder instability
- Hughston Clinc; Baseball Players and their Shoulder Injuries
