Causes of Distal Clavicle Osteolysis and Treatment Options

Distal clavicle osteolysis is shoulder joint pain at the end of the collarbone that is the result of bone disintegration and damage. The most common symptom is a sharp or aching pain at the junction of the acromioclavicular joint (AC joint) and collarbone. While the pain is usually felt during activity, there may also be a persistent tenderness around the joint during non-activity. Inflammation and swelling are also common manifestations.

The diagnosis of distal clavicle osteolysis can be usually made by physical examination, although imaging tests may be used to confirm the diagnosis or rule out other causes of shoulder pain. The good news is that treatment is usually straightforward—ice, rest, taking an anti-inflammatory, and physical therapy. In some instances, surgery may be needed.

Causes

Distal clavicle osteolysis is considered an overuse injury caused by repeated microfractures that the body attempts to repair. However, with each microfracture, the remodeling of bone becomes more jagged and uneven, placing stress on the end of the clavicle and causing the deterioration of cartilage on the adjacent AC joint where the clavicle meets the shoulder blade.

Common Causes

Distal clavicle osteolysis is seen most commonly in weightlifters or other athletes who perform heavy bench presses for a long period of time. Besides weightlifters, anyone who repeatedly lifts objects overhead (tennis players, swimmers) and/or carries heavy objects (construction workers, military workers) can develop distal clavicle osteolysis.

Rarer Causes

Much less commonly, distal clavicle osteolysis arises from direct trauma to the collarbone, like from a fall or direct blow.

When to See a Healthcare Provider

If you experience pain around the AC joint from an acute trauma or you develop tenderness and swelling around the AC joint, especially if you are a weightlifter or have a history of repetitive movements of the shoulder, be sure to see your healthcare provider for a proper diagnosis and treatment plan. In many cases, AC joint disorders, like distal clavicle osteolysis, respond to conservative therapies like ice and an anti-inflammatory medication. However, if pain persists, be sure to see an orthopedist, as surgery may be required.

Diagnosis

Diagnosis of distal clavicle osteolysis entails a thorough physical examination, often by an orthopedic surgeon or a sports medicine doctor. Testing may also be necessary.

Physical Examination

Pain when reaching across the chest is a typical symptom of AC joint problems. Healthcare providers can confirm this by performing a cross-body adduction test. Any pain caused by pressing the arm laterally across the chest is considered a positive result.

The stability of the AC joint will also be assessed. This is done by holding the distal collarbone between the thumb and forefinger and then moving the collarbone in different directions (forward, backward, up, and down), while stabilizing the acromion (a bone projection on the shoulder blade) with the other hand.

The shoulder joint may also be evaluated, as people with distal clavicle osteolysis generally retain a full range of motion of their shoulder.

Labs and Tests

With a suspected AC joint problem, your healthcare provider may order an AC injection test, often performed under the guidance of an X-ray or ultrasound. If a person experiences temporary pain relief after the steroid is injected, the test confirms a diagnosis of AC joint pain.

Your healthcare provider may also order blood tests, especially if he suspects a potential infection or that an inflammatory process is going on.

While an infected AC joint is not common, it may be suspected in a person with a weak immune system who has a fever and a tender, hot joint. In this case, a complete blood count will likely be ordered to see if there is an elevated number of white blood cells (your infection-fighting cells). In addition, a sample of the joint fluid (collected through joint aspiration) will need to be examined under a microscope to look for bacteria.

Other blood tests may be ordered to rule out other inflammatory processes. For example, tests for rheumatoid factor and antibodies to citrullinated peptides/proteins (anti-CCP antibodies) can evaluate for rheumatoid arthritis; a uric acid level test can check for gout. Since primary hyperparathyroidism can cause bone resorption of the collarbone, your healthcare provider may check a parathyroid hormone level and calcium blood level as well.

Imaging

After a physical examination and necessary lab tests, X-rays of the shoulder are performed. On X-ray, distal clavicle osteolysis would show up as an area of poor bone density or abnormal bone mineralization. It would be similar in appearance to osteoporosis, a condition where more bone is absorbed by the body than created.

Alternately, a magnetic resonance imagining (MRI) scan may be ordered if a healthcare provider suspects other causes of shoulder pain, either in addition to or separate from the suspected distal clavicle osteolysis.

Differential Diagnoses

As mentioned above, there are several health conditions that may cause pain at the AC joint and/or bone resorption at the distal end of the collarbone. Besides primary hyperparathyroidism, infection, or an inflammatory process like gout or rheumatoid arthritis, your healthcare provider may also need to perform imaging tests, such as an X-ray or MRI of the cervical spine (neck). This is because neck problems, like arthritis, can refer pain to the collarbone.

Treatment

Distal clavicle osteolysis is initially treated conservatively with rest, restriction of movement, and ice application over the AC joint. Any activity associated with the injury should be stopped. If there is severe pain, the shoulder may need to be held in a fixed position with an orthopedic sling.

Medications

In addition to rest and ice, medications to reduce inflammation and relieve pain are also essential to the healing process. Often times, a healthcare provider will recommend a nonsteroidal anti-inflammatory (NSAID). A steroid injection into the AC joint may also be performed to temporarily ease pain.

Physical Therapy

When the shoulder is reasonably healed and the inflammation has ceased, physical therapy would be started to safely restore range of motion and strength to the affected shoulder. The recommended exercises and reps will vary depending on your specific case; follow your therapist's instructions.

Surgery

In some cases, surgery may be needed if more conservative measures fail to provide relief. The surgery would involve the removal of the end of the collarbone, a technique healthcare providers refer to as the Mumford procedure. It is a common surgery used to correct other conditions affecting the AC joint, including severe osteoarthritis. It can be performed either through a small incision or arthroscopically.

With time, most people who undergo surgery can resume normal activities, including weight training and sports activities, with no loss of function. Recovery usually takes around three months, although some can return to activity faster with a structured course of physical therapy and rehabilitation.

Prevention

Due to the fact that most athletes find it difficult to completely eliminate bench pressing from their weightlifting routine, modifications can be made to ease the stress on the joint and collarbone. A few examples of modifications include:

• Narrowing the hand spacing on the barbell (less than 1.5 times the bi-acromial width)
• Placing towels on the chest so that the descent phase of the bench press ends 4 to 6 cm above the front of the chest

If you have recovered from distal clavicle osteolysis and your healthcare provider has given you the "OK" to continue working out, be sure you are clear on exactly what exercises you can and cannot do in order to avoid any further trauma to the AC joint.

A Word From Verywell

Being diagnosed with distal clavicle osteolysis can be a disheartening experience, especially if you are an active weightlifter or athlete. The good news is that many people get better with proper rest, ice, and pain control. Worst case scenario, surgery is needed, which is nearly always successful.