Impingement syndrome occurs when either a tendon or a bursa is pinched between bones of the shoulder. That impingement of structures may be from bone spurs, calcification of ligaments or tendons, or a humerus (upper arm bone) that is pulled up in the socket. The most common place for impingement is under a bone called the acromion process in an area called the subacromial space.
CAUSES: This may be caused by degenerative spurring of surrounding bones, bursitis, tendonitis, rotator cuff problems, or simply inflammation of surrounding tissues leading to decreased space in the area under the acromion process. Certain activities such as repetitive motions or overhead activities may predispose people to impingement syndrome.
SIGNS/SYMPTOMS: Pain in the shoulder (especially with overhead activity or reaching behind the back), weakness and loss of range of motion are the most common signs and symptoms. When raising the arm overhead to the side, there is normally a painful arc between about 70 to 120 degrees.
DIAGNOSIS: The history of pain and physical exam can tell a lot about shoulder problems. X-rays may be needed to visualize any spurring or malposition of the bones of the shoulder. An MRI can show more details of the tissues in the subacromial space revealing concurrent bursitis, tendonitis, or tendon tears.
TREATMENT: Any kind of anti-inflammatory, whether it is natural or synthetic, can help. Avoid repetitive motions, particularly ones that cause pain. Chiropractic adjustments may be beneficial depending on the cause of the impingement. Rehabilitative exercises are important to prevent muscle atrophy. Special care should be taken to avoid aggravating activities. Low level laser therapy (LLLT) may afford relief by decreasing inflammation and pain. In severe cases, surgery may be an option after conservative care has failed for a certain period of time.
COMPLICATIONS: Undiagnosed impingement syndrome may lead to further irritation of impinged structures such as bursitis, tendonitis, or tearing of the rotator cuff.
PROGNOSIS: The outcome with conservative care is usually pretty good once the cause of the impingement is discovered and addressed. The need for surgical intervention is rare, but this obviously may prolong the recovery.