Simply defined, arthritis is inflammation of one or more of your joints. In 2011, more than 50 million people in the U.S.A. reported that they had been diagnosed with some form of arthritis. In an arthritis shoulder, inflammation causes pain and stiffness.

Although there is no cure for arthritis of the shoulder, there are many treatment options available. Using these, most people with arthritis are able to manage pain and stay active.

Anatomy of the shoulder

Anatomy of the shoulder


The shoulder is a ball-and-socket type joint made up of three bones:

  1. Humerus (upper arm)
  2. Scapula (shoulder blade)
  3. Clavicle (collarbone)

The head of the humerus fits into a socket (called the “Glenoid”) in the shoulder blade. A group of muscles and tendons keeps the shoulder centred in the shoulder socket. These muscles are called the rotator cuff. They cover the head of humerus and attach it to your scapula. There is a lubricating sac called a bursa between the rotator cuff and the bone on top of your shoulder (acromion). This bursa allows the rotator cuff tendons to move freely when you move your arm in all directions.

The biceps muscle (in front of your upper arm) helps you bend your elbow and rotate your forearm. It also stabilizes the shoulder. The biceps muscle has two tendons that attach it to bones in the shoulder.

The Glenoid (socket) is lined with soft cartilage structure called the labrum. This tissue helps to stabilize the head of the humerus into the shoulder socket.

To provide you with effective treatment, your physician will need to determine which joint is affected and what type of arthritis you have.

Types of Shoulder Arthritis:

  1. Osteoarthritis (also known as “wear-and-tear” arthritis):
  2. Osteoarthritis is a condition that destroys the smooth outer covering (joint cartilage) of bone. As the cartilage wears away, it becomes thinned and rough, and the protective space between the bones decreases. The bones of the joint rub against each other (“bone-on-bone”), causing grinding sounds, stiffness and pain.

    Osteoarthritis usually affects people over 50 years of age and is more common in the acromion-clavicular joint than in the gleno-humeral shoulder joint.

    Damaged shoulder cartilage

    (Left) An illustration of damaged cartilage in the glenohumeral joint.

    (Right) This x-ray of the shoulder shows osteoarthritis and decreased joint space (arrow).

  3. Rheumatoid Arthritis
  4. Rheumatoid Arthritis

    Rheumatoid arthritis (RA) is a chronic disease that attacks multiple joints throughout the body. Rheumatoid arthritis is an autoimmune disease. This means that the immune system attacks its own tissues. In RA, the defences that protect the body from infection instead damage normal tissue (such as cartilage and ligaments) and soften bone.It is symmetrical, meaning that it usually affects the same joint on both sides of the body.

    The joints of your body are covered with a lining (synovium) that lubricates the joint and makes it easier to move. Rheumatoid arthritis causes the lining to swell, which causes pain and stiffness in the joint.

    Rheumatoid arthritis is equally common in both joints of the shoulder.

  5. Post-Traumatic Arthritis
  6. A form of osteoarthritis that develops after an injury (such as a fracture or dislocation of the shoulder)

  7. Rotator Cuff Tear Arthropathy
  8. Arthritis can also develop after a large, long-standing rotator cuff tendon tear. The torn rotator cuff can no longer hold the head of the humerus in the glenoid socket, and the humerus can move upward and rub against the acromion. This can damage the surfaces of the bones, causing arthritis to develop.The combination of a large rotator cuff tear and advanced arthritis can lead to severe pain and weakness, and the patient may not be able to lift the arm away from the side.

    Shoulder anatomy
  9. Avascular Necrosis
  10. Avascular necrosis (AVN) of the shoulder is a painful condition that occurs when the blood supply to the head of the humerus is disrupted. Because bone cells die without a blood supply, AVN can ultimately lead to destruction of the shoulder joint and arthritis.

    Causes of AVN include high dose steroid use, heavy alcohol consumption, sickle cell disease, and traumatic injury, such as fractures of the shoulder. In some cases, no cause can be identified; this is referred to as idiopathic AVN.


  • Pain
    • The most common symptom of arthritis of the shoulder. 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 worsen 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.
    • Night pain is common and sleeping may be difficult.
  • 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.

Medical History and Physical Examination

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
Shoulder X-Rays


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).

To confirm the diagnosis, your doctor may inject a local anaesthetic into the joint. If it temporarily relieves the pain, the diagnosis of arthritis is supported.


Nonsurgical Treatment

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 exercises 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 Omega fish oils, glucosamine and chondroitin sulfate may help relieve pain.

Surgical Treatment

Your doctor may consider surgery if your pain causes disability and is not relieved with nonsurgical options.

  1. Arthroscopy. Cases of mild glenohumeral arthritis may be treated with arthroscopy. 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.
  2. 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 prosthesis.
  3. Surgical Treatment

    (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:

  • Hemiarthroplasty: 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.
  • Resection arthroplasty: The most common surgical procedure used to treat arthritis of the acromion-clavicular joint is a resection arthroplasty. Your surgeon may choose to do this arthroscopically.In this procedure, a small amount of bone from the end of the collarbone is removed, leaving a space that gradually fills in with scar tissue.

Recovery: 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:

  1. Infection
  2. Excessive bleeding
  3. Blood Clots
  4. Damage to blood vessels or nerves

Your surgeon will discuss the possible complications with you before your operation.

Reverse Total Shoulder Replacement

Every year, thousands of conventional total shoulder replacements are successfully done in the United States for patients with shoulder arthritis. This type of surgery, however, is not as beneficial for patients with large rotator cuff tears who have developed a complex type of shoulder arthritis called "Rotator cuff tear arthropathy." For these patients, conventional total shoulder replacement may result in pain and limited motion, and reverse total shoulder replacement may be an option.

Description: A conventional shoulder replacement device mimics the normal anatomy of the shoulder: a plastic "cup" is fitted into the shoulder socket (glenoid), and a metal "ball" is attached to the top of the upper arm bone (humerus). In a reverse total shoulder replacement, the socket and metal ball are switched. The metal ball is fixed to the socket 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 to move the arm. In a healthy shoulder, the rotator cuff muscles help position and power the arm during range of motion. A conventional replacement device also uses the rotator cuff muscles to function properly. In a patient with a large rotator cuff tear and cuff tear arthropathy, these muscles no longer function. The reverse total shoulder replacement relies on the deltoid muscle, instead of the rotator cuff, to power and position the arm.

Reverse total shoulder replacement

(Left) Rotator cuff arthropathy.

(Right) The reverse total shoulder replacement allows other muscles — such as the deltoid — to do the work of the damaged rotator cuff tendons.

Candidates for Surgery

Reverse total shoulder replacement may be recommended if you have:

  • A completely torn rotator cuff that cannot be repaired
  • Cuff tear arthropathy
  • A previous shoulder replacement that was unsuccessful
  • Severe shoulder pain and difficulty lifting your arm away from your side or over your head
  • Tried other treatments, such as rest, medications, cortisone injections, and physical therapy, that have not relieved shoulder pain
Components of a reverse total shoulder replacement

The components of a reverse total shoulder replacement include the metal ball that is screwed into the shoulder socket, and the plastic cup that is secured into the upper arm bone.

Surgical Procedure

This procedure to replace your shoulder joint with an artificial device usually takes about 2 hours. Your surgeon will make an incision either on the front or the top of your shoulder. He or she will remove the damaged bone and then position the new components to restore function to your shoulder.

Surgical Complications

Surgical complications

Reverse total shoulder replacement is a highly technical procedure. Your surgeon will evaluate your particular situation carefully and discuss the risks of surgery with you.

Risks for any surgery include bleeding and infection. Complications specific to a total joint replacement include wear, loosening, or dislocation of the components. If any of these occur, the new shoulder joint may need to be revised, or re-operated on.

A typical follow-up x-ray of a reverse total shoulder replacement.

Long-Term Outcomes

After rehabilitation, you will most likely be able to lift your arm to just above shoulder height and bend your elbow to reach the top of your head or into a cupboard. Reverse total shoulder replacement provides outstanding pain relief and patient satisfaction is typically very high.

Early studies of the results of this surgery have been very promising, but currently no long-term studies exist. This is an area for future research.

Shoulder Replacement: Things you should now

The following information will help you prepare for your shoulder replacement surgery. It is important that you understand and follow the rehabilitation guidelines to give yourself the best chance of recovery from surgery. If you have any concerns or questions at any time, please discuss these with me or your therapist.

Things You Should Know:

  • You will need to visit the hospital for a pre-admission consultation with a nursing sister. She will identify and address any underlying medical problems and assist with the administrative process.
  • Some medications may need to be stopped before surgery. (Non-steroidal anti-inflammatory medications, such as aspirin, ibuprofen, and naproxen sodium and most arthritis medications). If you take blood thinners, either your primary care doctor or cardiologist will advise you about stopping these medications before surgery
  • You will require a general anaesthetic ± regional block.
  • The operation normally takes between 90-120 minutes.
  • You will have an incision at the front of your shoulder
  • The usual hospital stay is 3 or 4 nights
  • Home Planning: Making simple changes in your home before surgery can make your recovery period easier. For the first several weeks after your surgery, it will be hard to reach high shelves and cupboards. Before your surgery, be sure to go through your home and place any items you may need afterwards on low shelves. When you come home from the hospital, you will need help for a few weeks with some daily tasks like dressing, bathing, cooking, and laundry. If you will not have any support at home immediately after surgery, you may need a short stay in a rehabilitation facility until you become more independent.
  • The dressings are waterproof, so you can shower (out of the sling) resting your operated arm on your abdomen or by your side
  • Apply an ice-pack regularly to your operated shoulder in the first few days after surgery to reduce pain and swelling
  • Take regular pain relief in the first few days, then as required
  • You will need to wear a sling for 6 weeks
  • During this time, you can come out of the sling three times a day to do your physiotherapy exercises.
  • After 6 weeks – you can come out of the sling and you are allowed to perform usual gentle activities of daily living
  • Driving is allowed once you come out of your sling
  • Dr’s Visits: 2 weeks, 6 weeks, 3 months & 6 months, 1 year, 2 years, 5 years, 10 years
  • Rehabilitation Guidelines:
    • 0-6 weeks: Sling full-time, NO active use of the operated arm
    • 6-12 weeks: Active use of arm for gentle activities of daily living (NO lifting more than 2kg, no sudden pulling or pushing motions)
    • 3-6 months: Normal use of arm (but NO heavy lifting, i.e. >5kg, or sudden lifting or pulling motions)
    • 6 months: Resume full activities including progressive return to sporting activities. If you have access to a heated pool or Hydrotherapy centre, then I strongly recommend that you take advantage of this form of therapy to aid with your rehabilitation.

The Future:

  1. Research is being conducted on shoulder arthritis and its treatment. In many cases, it is not known why some people develop arthritis and others do not. Research is being done to uncover some of the causes of arthritis of the shoulder.
  2. Joint lubricants, which are currently being used for treatment of knee arthritis, are being studied in the shoulder.
  3. New medications to treat rheumatoid arthritis are being investigated.
  4. Much research is being done on shoulder joint replacement surgery, including the development of different joint prosthesis designs.
  5. The use of biologic materials to resurface an arthritic shoulder is also being studied. Biologic materials are tissue grafts that promote growth of new tissue in the body and foster healing.