Acromioclavicular (AC) Joint Arthritis

Also known as acromioclavicular (AC) joint arthrosis and osteoarthritis of the AC joint, AC joint arthritis is the gradual deterioration of the cartilage located at the acromion and the clavicle within the AC joint.

AC joint arthritis is unlike glenohumeral arthritis, or shoulder arthritis, which is the deterioration of the cartilage of the long arm bone, the humerus, located at the socket of the shoulder joint.

Those suffering from AC joint arthritis may experience pain and tenderness near the front of the shoulder and around the joint, discomfort while sleeping, pain during certain arm and shoulder movements that may span the shoulder area, chest and neck, and mild swelling. There may also be a reduction in range of motion.

Risk Factors
Most often diagnosed in those over the age of 40, the primary cause of AC joint arthritis is general use. Though some repetitive activities that place unusual and constant stress on the shoulder joint, or an earlier AC joint injury such as shoulder separation, puts some at greater risk than others for the disease. Also more susceptible to the disease include workers who must use their arms for extended periods of time or athletes involved in overhead lifting. Blunt force to the shoulder, in either contact sports or in an accident, also leave an individual susceptible.

Diagnosis and Treatment
Following a thorough examination and patient history review, an x-ray may be indicated in order to determine the extent of joint damage. A series of x-rays over time can help determine the rate of progression.

Treatment is determined based on the effect the arthritis has had on a patient's joint at the time of diagnosis, as well as the type of joint effected. It may involve conservative treatment - including cold compression, anti-inflammatory medications, refrain from inflammatory activity, cortisone injections, and rehabilitation and occupational therapy to improve range of motion.

In more advanced cases nonresponsive to conservative treatment, either a resection arthropolasty or a complete shoulder replacement may be indicated.