Causes of Shoulder Impingement Syndrome
Shoulder impingement is often caused by repetitive motions, particularly overhead activity. Activities which have a higher risk of producing shoulder impingement include: Sports, such as swimming, baseball, volleyball, tennis, weight lifting, tennis, surfing, and water polo Painting (particularly high walls or ceilings). Stocking high shelves repeatedly Factors which may contribute to shoulder impingement: Narrow space between tendons and bones: Structural abnormalities, arthritis, and bone spurs can result in a narrower space in which the rotator cuff and bursa can move, making them more likely to get pinched. Inflammation: Overuse or repetitive irritation can lead to inflammation and swelling. This inflammation alone can be painful, but becomes exacerbated when it leads to impingement. Bone and joint abnormalities: Structural abnormalities can result in a narrower space between the tendons and the bones. Some people are born with a curved acromion, which narrows the space, but others develop arthritis and bone spurs, which can also narrow the space. When there is less room for the rotator cuff and bursa to move, they are more likely to get pinched. Shoulder instability: The shoulder is the most mobile joint in the body, but that mobility comes with a price—instability. Underlying shoulder instability is a common cause of impingement in young athletes.