I found a few things on the Internet about something called snapping scapular syndrome. Most of what I found was on your site. What else can you tell me about this problem?
The snapping scapula syndrome is characterized by a loud pop or crack when the arm is raised up overhead. The medical term for this sound is crepitus. The sound is made by some soft tissue rubbing between the scapula and the thoracic wall. The tissue caught between these two structures could be a bursa, tendon, or muscle. The person with this problem may or may not experience pain with the movement.
A little understanding of the upper quadrant anatomy might help understand what's going on with this condition. Then we can talk about what causes it. The scapula (shoulder blade) is an amazing anatomical structure. It is suspended over the ribs between the spine and the arm by only two ligaments. There isn't a real joint between the scapula and the trunk.
Three layers of muscle and bursae (plural for bursa) support this structure. The bursae are small fluid-filled sacs designed to reduce friction between muscle or tendon and bone. These layers (superficial, intermediate, and deep) form a smooth surface for the scapula to move, glide, and rotate over. Because there is movement but no actual joint, this connection is considered a pseudojoint.
The scapula gives the glenohumeral joint (shoulder) a stable base from which to operate (move). The scapula itself slides, glides, and rotates in a 2:1 ratio with the shoulder. This means that for every two degrees of shoulder motion (flexion or abduction), the scapula moves one degree over the thoracic wall.
Scapulothoracic movement requires proper length-tension ratios between the scapular bone and all of the muscles around it. Any change in the glenohumeral-to-scapulothoracic ratio can result in altered or compromised shoulder motion. One particular problem called the snapping scapula syndrome is an example of what can happen when any one of these layers is disrupted for any reason.
There isn't one reason why someone develops snapping scapula syndrome. Studies show that sometimes there's a change in the shape or curvature of the scapula. After years of movement, the repetitive motion eventually causes a wear pattern that results in the snapping scapula syndrome. When a bursa is involved, the snapping problem could start as an isolated injury or it could be the result of repetitive (abnormal) motions of the scapulothoracic joint.
A less common cause is the development of a benign tumor called an osteochondroma. Bone spurs, scapular or rib fractures, nerve injuries with muscle wasting and weakness, or other types of tumors have also been linked with the snapping syndrome. And any surgery to the upper quadrant (e.g., breast implants or other breast cosmetic procedures, removal of a rib pressing on a nerve) can result in muscular changes that contribute to the development of the scapular snapping syndrome.
Anyone who has this problem should see an orthopedic specialist for a formal diagnosis and determination of the underlying cause. If there are no tumors requiring medical treatment, then conservative care with pain relievers and exercise may be advised. Sometimes, when the bursa are inflamed, steroid injections can be helpful.
Meredith A. Lazar, MD, et al. Snapping Scapula Syndrome. In Journal of Bone and Joint Surgery. September 2009. Vol. 91. No. 9. Pp. 2251-2262.
*Disclaimer:* The information contained herein is compiled from a variety of sources. It may not be complete or timely. It does not cover all diseases, physical conditions, ailments or treatments. The information should NOT be used in place of visit with your healthcare provider, nor should you disregard the advice of your health care provider because of any information you read in this topic.