Shoulder osteoarthritis (degenerative arthritis of the shoulder)
Your risk of developing osteoarthritis of the shoulder - with its pain and physical limitations - increases with age. But an injury such as a dislocated shoulder can lead to shoulder osteoarthritis even in young people. Here is information about the causes of and treatments for shoulder osteoarthritis. Read on to learn how an arthritic shoulder can affect your range of motion and ability to do everyday things, and discover ways to treat and manage osteoarthritis of the shoulder.
What is osteoarthritis?
Osteoarthritis - also known as degenerative joint disease - occurs when the cartilage that covers the tops of bones, known as articular cartilage, degenerates. Trauma (injury at a microscopic or more major level) to the joint triggers an immune reaction, which - in an ill-fated attempt to repair the damage - causes inflammation that leads to a breaking down of cartilage tissue, causing pain, swelling and deformity.
The firm rubbery cartilage is primarily made up of water and proteins. When the cartilage is damaged, attempts by the immune system to repair the damaged cartilage cause it to swell. The cartilage becomes thin, soft and cracked, exposing the bone beneath and leading to the formation of small cysts and new outgrowths of bone called osteophytes, which further disrupt the way the joint works and aggravate the problem. The joint space becomes narrowed, further altering the mechanics and adding to the stresses within the joint. Other tissues in the joint such as the surrounding membrane (the synovium) ligaments and tendons may also be affected. This degeneration is a gradual process that may go on over many years although occasionally it is more acute.
What is osteoarthritis of the shoulder?
The shoulder is made up of two joints, the acromioclavicular (AC) joint and the glenohumeral, also called scapulothoracic, joint. The AC joint is the point where the collarbone, or clavicle, meets the acromion, which is the tip of the shoulder bone. The glenohumeral joint is the point where the top of the arm bone, or humerus, meets the shoulder blade, or scapula. Osteoarthritis is more commonly found in the AC joint.
Who gets osteoarthritis of the shoulder?
Osteoarthritis most often occurs in people who are over 50 years old. In younger people osteoarthritis can result from an injury or trauma such as a fractured or dislocated shoulder. This is known as post-traumatic arthritis. Osteoarthritis may also have a hereditary component.
What are the symptoms of osteoarthritis of the shoulder?
As with most types of osteoarthritis, pain is a key symptom. A person with shoulder arthritis is likely to have pain while moving the shoulder as well as after moving the shoulder. The person can even have pain while sleeping.
Another symptom may be a limited range of motion. This limitation can be seen when you are trying to move your arm. It can also be evident if someone is moving your arm to assess range of motion. Moving the shoulder might also produce a clicking or creaking noise.