Many forms of arthritis and related conditions that affect the joints, muscles and/or bones can cause problems like pain, stiffness and swelling in the shoulders. Here are some diseases that can affect the shoulders.

  • Osteoarthritis. The most common form of arthritis, osteoarthritis is a chronic condition characterized by the breakdown of the cartilage that cushions the ends of the bones where they meet to form joints. This breakdown causes the bones to rub against each other, causing stiffness, pain and loss of movement in the joint. Bony projections, or spurs, can develop around the joint. In the shoulder, osteoarthritis often occurs after an injury.

Learn more about osteoarthritis.

Experts answer your questions about osteoarthritis.

  • Rheumatoid arthritis. Rheumatoid arthritis is a chronic inflammatory disease of the joints that occurs when the body’s immune system – which normally protects us from infection – mistakenly attacks the synovium, the thin membrane that lines the joints. The result can be joint damage, pain, swelling, inflammation, loss of function and disability. The joint involvement of rheumatoid arthritis is symmetrical. That means if one shoulder is affected the other likely will be too.

Learn more about rheumatoid arthritis.

  • Juvenile arthritis. Juvenile arthritis is the term used to describe arthritis when it begins before age 16. There are several different types of juvenile arthritis that can cause pain, swelling and potentially destruction of the shoulders.

Learn more about juvenile arthritis.

  • Gout. Gout is a form of arthritis that occurs when excess uric acid, a bodily waste product circulating in the bloodstream, is deposited as needle-shaped monosodium urate crystals in tissues of the body, including the joints. For many people, the first symptom of gout is excruciating pain and swelling in the big toe – often following a trauma, such as an illness or injury. Subsequent attacks may occur off and on in other joints, typically the feet, ankles, hands, wrists, elbows and knees. Shoulder involvement is less common, but can occur.

Learn more about gout.

  • Calcium pyrophosphate dihydrate crystal deposition disease (pseudogout). Like gout, pseudogout occurs when crystals form within the joints. With pseudogout, however, the crystals are formed from a salt called calcium pyrophosphate dihydrate. Although pseudogout occurs mostly in older people, it can affect younger people, particularly if they have other health problems. And like gout, pseudogout can cause intense pain and swelling, which often comes during the night. Pseudogout most commonly affects the knee, wrist and shoulder joints.

Learn more about pseudogout.

  • Reactive arthritis. Reactive arthritis is a chronic form of arthritis that often occurs following an infection of the genital, urinary or gastrointestinal system. Features of reactive arthritis include inflammation and swelling of the joints, eyes and structures within the gastrointestinal or genitourinary tracts, such as intestines, kidneys or bladder. Although the ankles, knees and joints of the feet often are the first joints affected by reactive arthritis, it also can affect the shoulder.

The National Institute of Arthritis and Musculoskeletal and Skin Diseases answers your questions about reactive arthritis.

  • Lupus. Lupus is a chronic autoimmune disease, meaning the body's immune system creates antibodies that attack healthy tissues, including the joints, skin, heart, lungs, and kidneys. The joints farthest from the body, such as those of the hands and feet, are most commonly affected by lupus; however, muscle inflammation that often accompanies lupus usually affects the shoulders as well as the muscles of the neck, pelvis, thighs and upper arms.