The shoulder is the joint most commonly affected by arthritis after the hip and the knee. While shoulder osteoarthritis is the most common form of arthritis, there are several forms of shoulder arthritis that can occur, resulting in pain, stiffness, and loss of motion that disrupts daily activities.
What is shoulder arthritis?
The shoulder has two joints, one of which is the glenohumeral joint, or the large ball-and-socket joint. Cartilage covers the socket (the glenoid) and the ball (the humeral head) in the shoulder joint. Shoulder arthritis is when the cartilage is damaged and breaks down.
The stages of shoulder arthritis
Shoulder arthritis develops in stages:
- The cartilage gets soft.
- The cartilage develops cracks in the surface.
- The cartilage deteriorates and flakes, or “fibrillates.”
- The cartilage wears away and exposes the bone.
The cartilage, however, doesn't wear away all over the surface of the joint. Instead, certain areas wear out differently than others, causing the surface to become irregular. Eventually, this leads to bone-on-bone traction in the joint.
5 types of shoulder arthritis
There are five types for arthritis that can occur in the shoulder joint, including:
Osteoarthritis: The “wear-and-tear” form of arthritis, osteoarthritis in the shoulder is where the ball and socket of the shoulder wear out and the normal cartilage covering deteriorates due to aging. As a result, the patient develops pain that’s from literal bone-to-bone contact with the shoulder.
Rheumatoid arthritis (RA): A chronic autoimmune disease, RA attacks multiple joints throughout the body, causing the lining of the joint to swell, which produces pain and stiffness.
Posttraumatic arthritis: This form of osteoarthritis develops from an injury, such as a fracture or dislocation in the shoulder.
Rotator cuff tear arthropathy: When large rotator cuff tears are left untreated, rotator cuff tear arthropathy can develop and cause shoulder arthritis. Treatment can be difficult, according to the Hospital for Special Surgery, because there is damage to the soft tissue as well as the joint surface.
Avascular necrosis: Also known as osteonecrosis, in this condition, the blood supply to the bone forming the ball of the shoulder is stopped due to disease, traumatic injuries, or other causes, resulting in the collapse and death of the bone segment. This loss in bone support causes the cartilage to become damaged, which can lead to shoulder arthritis.
What does shoulder arthritis feel like?
According to Dr. Vladimir Alexander, Founding Partner of Alexander Orthopaedics, “Shoulder arthritis feels like pain in the ball and socket, catching and/or grinding upon movement. Pain is usually in the back of the shoulder or in the armpit area towards the back of the armpit.”
Shoulder arthritis symptoms
Shoulder arthritis symptoms include:
- Pain in the shoulder joint: A major sign of arthritis, pain in the front, side or back of the shoulder can occur while the arm is in use or not, and at any time. The pain is often worse after exercising, or lifting and carrying heavy objects.
- Stiffness and loss of range of motion: As the arthritis in the shoulder progresses, you may experience stiffness and reduced range of motion in the shoulder. Your daily activities can be limited as your motion decreases and you experience pain.
- Cracking (crepitus), grinding or catching: Since the surface of the shoulder is irregular, you may feel the shoulder lock up or slide in certain positions.
What causes shoulder arthritis?
While the cause of shoulder arthritis depends on the type, it is generally caused by either a specific incident or factor, such as a previous injury, shoulder dislocation, infection, or rotator cuff tears, or it does not have a specific cause and instead is related to age, genes, or sex.
While shoulder arthritis commonly occurs in people over 50, younger people can also develop shoulder arthritis after trauma or injury to the shoulder. An article published in American Family Physician states that certain occupations, such as heavy construction or overhead sports, are also risk factors. Arthritis can be hereditary, meaning it runs in families as well.
How is shoulder arthritis diagnosed?
Your doctor will first conduct a physical examination, evaluating the following:
- Tenderness and stiffness
- Weakness in the muscles
- Range of motion
- Any signs of current injury to the tendons or muscles, as well as previous injury
- Involvement of other joints (relevant for rheumatoid arthritis)
After the physical exam, your doctor may order an X-ray to see if there are any changes in the bone, formation of bone spurs, or narrowing of the joint space. A CT scan or MRI can show more detail in the shoulder tissue if needed.
What is treatment for shoulder arthritis?
According to Dr. Alexander, “Shoulder arthritis is treated with anti-inflammatory medicine, activity modification, physical therapy, and cortisone shots. If all of that doesn't work, then a shoulder replacement may be done.”
Ice and heat
Applying moist heat helps with pain. Icing your shoulder for 20-30 minutes per day can also ease pain and reduce inflammation.
Anti-inflammatory medications like naproxen, ibuprofen and aspirin can help reduce inflammation and ease pain in the shoulder. These medications should be taken with food as they can irritate the stomach lining.
Avoiding activities that put stress on the arm and shoulder, such as certain sports or exercises, can help reduce pain.
Physical therapy can help improve the range of motion in the shoulder. However, Dr. Alexander states that it’s important to consult with an experienced, certified physical therapist before engaging in any type of physical therapy exercises: “In terms of exercises, really someone with shoulder arthritis should see a certified, licensed physical therapist because just to go online doesn’t really work very well — they should be guided by a therapist to know what to do.”
While corticosteroid shots can help reduce inflammation and pain, the effect is often temporary.
In a shoulder arthroscopy, the orthopedic surgeon can clean out (“debride”) the inside of the joint. Arthroscopic shoulder repair is often recommended in lower grades of arthritis and can help with pain relief for shoulder arthritis. However, it will not eliminate arthritis from the joint and is not considered a permanent solution.
Total shoulder replacement
Shoulder arthroplasty, or total shoulder replacement, can treat shoulder arthritis that does not respond to other treatments. There are two types of shoulder replacements:
- Standard total shoulder replacement: In this procedure, parts of the ball and socket are replaced with artificial parts.
- Reverse total shoulder replacement: In this procedure, the ball and socket sides of the joint switch places. According to Dr. Alexander, “A reverse replacement of the shoulder is for somebody who has an arthritic shoulder and a damaged rotator cuff.”
Shoulder arthritis treatment and recovery
Shoulder arthritis can cause significant pain, stiffness, and discomfort in the shoulder, disrupting your daily life and activities. You don’t have to live in pain. At Alexander Orthopaedics, our expert orthopedic surgeons and physical therapists will work with you to create a customized treatment plan so that you can treat your shoulder arthritis and get back to doing what you love.