Arthritis can also develop in the acromioclavicular or AC joint of the shoulder. It can be due to rheumatoid arthritis, osteoarthritis or post-traumatic arthritis. The condition is quite common with advancing age but rheumatoid arthritis can cause the condition at any age.
Rheumatoid arthritis
Rheumatoid arthritis is described as an autoimmune condition where the body initiates an immune response to the synovial tissue of the joint. This condition can affect any joint in the body at various ages. The AC joint can be affected by this arthritis.
Osteoarthritis
Osteoarthritis is known to cause soreness of the joint especially among the elderly. The characteristics of this type of arthritis include diminished joint space or constriction, development of extra bone or osteophytes and increased bony density below the cartilage.
Individuals who perform overhead work such as in construction or weightlifting face a higher risk for develop osteoarthritis of the AC joint.
Post-traumatic arthritis
When it comes to post-traumatic arthritis, it is considered as a sub-type of osteoarthritis that develops after sustaining a dislocation, fracture or joint separation. In chronic cases of AC joint separations, it can progress to post-traumatic arthritis.
What are the indicative symptoms?
The signs and symptoms of AC joint arthritis do not always associate well with the X-ray results. The osteophytes or bony growths can be evident at the clavicular region of the joint that might be linked with the symptoms.
The pain is usually linked to activities that involve overhead movement as well as moving the arm towards the middle of the body or adduction.
Diagnosing AC joint arthritis
The doctor will conduct a full examination of the shoulder to check if there is swelling or tenderness at the AC joint. In most cases, the cross-arm test is performed in which the individual is instructed to touch the other shoulder with the affected arm. The test is done to check if it triggers pain. The findings might also be present in various conditions that affect the AC joint and the shoulder.
MRIs and X-rays might be required for further assessment of the joint. An X-ray can reveal any arthritic changes but these may or may not correlate with the actual degree of pain experienced by the individual. As for the MRI results, it shows edema or swelling that might be linked with the symptoms.
Treatment
The conservative treatment options for arthritis of the AC joint include rest, non-steroidal anti-inflammatory drugs (NSAIDs) and activity modification. In some cases, a steroid can be injected into the joint.
Surgery is usually the last resort if the conservative measures were not effective in alleviating the symptoms. Surgery is utilized to provide space in the clavicular region of the joint to increase the total joint space to minimize the symptoms. In addition, the bony growths are also removed.