The most common cause leading to a shoulder replacement is osteoarthritis, or wear and tear arthritis. Osteoarthritis can occur without any injury to the shoulder, but it is uncommon. This is in large part because the shoulder is not a weight-bearing joint. Wear and tear arthritis is more common in the hip and knee. More commonly, osteoarthritis occurs many years after an injury to the shoulder. A shoulder dislocation can result in instability of the shoulder that leads to chronic instability. Repeated dislocations over many years damage the joint leading to arthritis. Some fractures of the shoulder can also lead to arthritis. The problem with aseptic necrosis described above can also lead to osteoarthritis.

Other types of arthritis affect the shoulder joint as well. Systemic diseases, such as rheumatoid arthritis, affect all the joints of the body. The result is much the same as osteoarthritis, making the shoulder painful and difficult to use due to the pain.