Acromioclavicular Arthritis Causes, Symptoms & Treatment

The acromioclavicular (AC) joint is a joint in the shoulder that forms where the clavicle bone meets the highest part of the scapula (shoulder blade) called the acromion. The AC joint allows you to raise your arm over your head and move your arm across your body. Arthritis is a general term given to joint disease that leads to inflammation, pain, and stiffness. When arthritis affects the AC joint, this is called acromioclavicular arthritis. Weightlifters often get a related condition called “weightlifter’s shoulder.” The weightlifter’s shoulder is osteolysis (breakdown of bone) of the distal (the end farthest from the neck) portion of the collarbone.

The AC joint degeneration often manifests as stiffness and pain during upper body movement, particularly at the shoulder tip. As a result, shoulder tip arthritis can significantly impact daily function and athletic performance.

Acromioclavicular arthritis develops over time, with repetitive movements that place stress on the AC joint. A flexible tissue, called cartilage, covers and protects the end of the clavicle and the acromion, allowing these two bones to interact and move without rubbing up against each other. When the cartilage is inflamed, it can degenerate, leaving the clavicle and acromion susceptible to grinding against each other. This can lead to the development of tiny fractures in the distal (farthest from the head) end of the collarbone. When these fractures occur, this is called distal clavicular osteolysis or “weightlifter’s shoulder.”
Collarbone joint pain from this condition is a common complaint among active individuals, especially those engaged in repetitive overhead or cross-body arm movements.

AC arthritis can also occur years after an injury to the AC joint such as a AC separation.

AC arthritis is common in these sports:

Bodybuilding
Football
Rugby
Soccer
Weightlifting

You may have AC arthritis if you are experiencing one or more of the following symptoms:

• Pain on the top of the shoulder that may radiate to the neck
• Increased pain after working out
• Limited or reduced range of motion of your arm when reaching across your chest

If you’re experiencing symptoms of AC joint stiffness, collarbone joint pain, or acromioclavicular arthritis, make an appointment with an orthopedic specialist. Getting an accurate diagnosis is essential to getting the treatment you need. During your appointment, your doctor will examine your shoulder and look for signs of arthritis and/or osteolysis, like:

• Pain or tenderness when pressing on the AC joint
• Pain with reaching across the chest

Non-operative treatment

AC joint degeneration and weightlifter’s shoulder are initially treated using conservative, non-operative treatments. If you have been diagnosed with acromioclavicular arthritis or with weightlifter’s shoulder, non-operative treatments that may be prescribed to you by your doctor may include:

• Avoiding activities that cause pain
• Regular icing to decrease inflammation
• Anti-inflammatory medications to reduce inflammation
• Corticosteroid injection to reduce inflammation and pain (administered to you by your orthopedic specialist)
• Physical therapy to increase range of motion

Try these exercises to help address your condition:

Below is a PDF of the Exercise Program

AC Arthritis

If non-surgical treatments do not relieve your symptoms, your doctor may recommend surgery. Acromioclavicular arthritis and weightlifter’s shoulder are treated surgically by removing the damaged portion of the clavicle and/or the cartilage of the AC joint.

The goal of surgery for shoulder tip arthritis and weightlifter’s shoulder is to relieve pain by removing the damaged end of the clavicle. This procedure is called the Mumford procedure or AC joint arthroplasty. The removal of this piece of the clavicle relieves pain without resulting in loss of range of motion or strength. This can be done arthroscopically or through a small incision.

Recovery time for acromioclavicular arthritis will depend on the severity of the arthritis as well as the treatments applied. If the disease is minimal, non-operative treatments can alleviate pain within a matter of weeks. Full rehabilitation following surgery can take up to three months.

You should only return to normal activities when directed by your doctor. Typically, you will need to be pain-free and regain full range of motion and strength before being cleared to play. If you don’t need surgical treatment, modifications in weight lifting routines can help prevent the recurrence of this condition.