Also known as “wear-and-tear” arthritis, osteoarthritis is a condition that destroys the smooth outer covering (articular cartilage) of bone. As the cartilage wears away, it becomes frayed and rough, and the protective space between the bones decreases. During movement, the bones of the joint rub against each other, causing pain.
Osteoarthritis usually affects people over 50 years of age and is more common in the acromioclavicular joint than in the glenohumeral shoulder joint.
Pain. The most common symptom of arthritis of the shoulder is pain, which is aggravated by activity and progressively worsens.
If the glenohumeral shoulder joint is affected, the pain is centered in the back of the shoulder and may intensify with changes in the weather. Patients complain of an ache deep in the joint.
The pain of arthritis in the acromioclavicular (AC) joint is focused on the top of the shoulder. This pain can sometimes radiate or travel to the side of the neck.
Someone with rheumatoid arthritis may have pain throughout the shoulder if both the glenohumeral and AC joints are affected.
-Limited range of motion. Limited motion is another common symptom. It may become more difficult to lift your arm to comb your hair or reach up to a shelf. You may hear a grinding, clicking, or snapping sound (crepitus) as you move your shoulder.
As the disease progresses, any movement of the shoulder causes pain. Night pain is common and sleeping may be difficult.
After discussing your symptoms and medical history, your doctor will examine your shoulder.
During the physical examination, your doctor will look for:
- Weakness (atrophy) in the muscles
- Tenderness to touch
- Extent of passive (assisted) and active (self-directed) range of motion
- Any signs of injury to the muscles, tendons, and ligaments surrounding the joint
- Signs of previous injuries
- Involvement of other joints (an indication of rheumatoid arthritis)
- Crepitus (a grating sensation inside the joint) with movement
- Pain when pressure is placed on the joint
-X-rays are imaging tests that create detailed pictures of dense structures, like bone. They can help distinguish among various forms of arthritis.
-X-rays of an arthritic shoulder will show a narrowing of the joint space, changes in the bone, and the formation of bone spurs (osteophytes).
As with other arthritic conditions, initial treatment of arthritis of the shoulder is nonsurgical. Your doctor may recommend the following treatment options:
- Rest or change in activities to avoid provoking pain. You may need to change the way you move your arm to do things.
- Physical therapy may improve the range of motion in your shoulder.
- Nonsteroidal anti-inflammatory medications (NSAIDs), such as aspirin or ibuprofen, may reduce inflammation and pain. These medications can irritate the stomach lining and cause internal bleeding. They should be taken with food. Consult with your doctor before taking over-the-counter NSAIDs if you have a history of ulcers or are taking blood thinning medication.
- Corticosteroid injections in the shoulder can dramatically reduce the inflammation and pain. However, the effect is often temporary.
- Moist heat
- Ice your shoulder for 20 to 30 minutes two or three times a day to reduce inflammation and ease pain.
- If you have rheumatoid arthritis, your doctor may prescribe a disease-modifying drug, such as methotrexate.
- Dietary supplements, such as glucosamine and chondroitin sulfate may help relieve pain. (Note: There is little scientific evidence to support the use of glucosamine and chondroitin sulfate to treat arthritis. In addition, the U.S. Food and Drug Administration does not test dietary supplements. These compounds may cause negative interactions with other medications. Always consult your doctor before taking dietary supplements.
Your doctor may consider surgery if your pain causes disability and is not relieved with nonsurgical options.
-Arthroscopy. Cases of mild glenohumeral arthritis may be treated with arthroscopy, During arthroscopy, the surgeon inserts a small camera, called an arthroscope, into the shoulder joint. The camera displays pictures on a television screen, and the surgeon uses these images to guide miniature surgical instruments. Because the arthroscope and surgical instruments are thin, the surgeon can use very small incisions (cuts), rather than the larger incision needed for standard, open surgery. During the procedure, your surgeon can debride (clean out) the inside of the joint. Although the procedure provides pain relief, it will not eliminate the arthritis from the joint. If the arthritis progresses, further surgery may be needed in the future.
-Shoulder joint replacement (arthroplasty). Advanced arthritis of the glenohumeral joint can be treated with shoulder replacement surgery, in which the damaged parts of the shoulder are removed and replaced with artificial components, called a prosthesis.
(Left) A conventional total shoulder replacement (arthroplasty) mimics the normal anatomy of the shoulder. (Right) In a reverse total shoulder replacement, the plastic cup inserts on the humerus, and the metal ball screws into the shoulder socket.
Replacement surgery options include:
- Just the head of the humerus is replaced by an artificial component.
- Total shoulder arthroplasty. Both the head of the humerus and the glenoid are replaced. A plastic “cup” is fitted into the glenoid, and a metal “ball” is attached to the top of the humerus.
- Reverse total shoulder arthroplasty. In a reverse total shoulder replacement, the socket and metal ball are opposite a conventional total shoulder arthroplasty. The metal ball is fixed to the glenoid and the plastic cup is fixed to the upper end of the humerus. A reverse total shoulder replacement works better for people with cuff tear arthropathy because it relies on different muscles — not the rotator cuff — to move the arm.
- An alternative joint reconstruction is humeral head resurfacing. In this procedure a small amount of the affected bone is removed from the humeral articulating surface (head) and replaced by a smooth metal cap. This is a particularly good treatment for active young patients as it typically provides good relief and is easy to revise if the condition deteriorates in the future.
Surgical treatment of arthritis of the shoulder is generally very effective in reducing pain and restoring motion. Recovery time and rehabilitation plans depend upon the type of surgery performed.
Complications. As with all surgeries, there are some risks and possible complications. Potential problems after shoulder surgery include infection, excessive bleeding, blood clots, and damage to blood vessels or nerves.
Your surgeon will discuss the possible complications with you before your operation.