Frozen shoulder

Frozen shoulder, also known as adhesive capsulitis, is a condition characterized by stiffness and pain in your shoulder joint. In one stage of the disorder — the freezing stage — your shoulder's range of motion is notably reduced. Frozen shoulder usually affects one shoulder at a time, although some people may eventually develop it in the opposite shoulder.

With treatments recommended by their doctors and through self-care efforts, most people eventually regain nearly full shoulder range of motion and strength as signs and symptoms improve.

Frozen shoulder typically develops slowly, and in three stages. Each of these stages can last a number of months:

For some people, the pain worsens at night, sometimes disrupting normal sleep patterns.

Doctors don't know the precise cause of frozen shoulder. It can occur after an injury to your shoulder or prolonged immobilization of your shoulder, such as after surgery or an arm fracture. People who have diabetes have a greater risk of frozen shoulder. For this reason, frozen shoulder may have an autoimmune component, meaning your immune system may begin to attack the healthy parts of your body — in this case, the supporting structures of your shoulder. People with other health conditions, including heart disease, lung disease and hyperthyroidism, also may have an increased risk of developing frozen shoulder.

Your shoulder is a ball-and-socket joint. The round end of your upper arm bone (humerus) fits into a shallow groove on your shoulder blade (scapula), much like a golf ball rests on a tee. Tough connective tissue, called the shoulder capsule, surrounds the joint and plays an important role in movement.

When frozen shoulder occurs, the shoulder capsule becomes inflamed and stiff. The inflammation may cause bands of tissue (adhesions) to develop between your joint's surfaces. Synovial fluid, which helps to keep your joint lubricated and moving smoothly, may also decrease. As a result, pain and subsequent loss of movement may occur. In some cases, mobility may decrease so much so that performing everyday activities — such as combing your hair, brushing your teeth or reaching for your wallet in your back pocket — is difficult or even impossible.

Although the exact cause is unknown, certain factors may increase your risk of getting frozen shoulder. These factors include:

If you experience significant pain combined with stiffness and restricted range of motion in your shoulder, you should see your doctor to determine if you have frozen shoulder.

The primary means of diagnosing frozen shoulder is a physical examination. During the exam, your doctor may test your active movement (movement without assistance) by asking you to raise and lower your arm to the front, sides and back of your body. Your doctor may also test your passive movement (movement with assistance) by manually moving your arm and shoulder to determine your range of motion. As well, he or she may press on parts of your shoulder to see what might cause pain. Loss of both active and passive movement and a pattern of generalized (diffuse) shoulder tightness and pain are strong indicators of frozen shoulder.

Obtaining an X-ray image of your shoulder joint allows your doctor to assess the bones of your shoulder. A magnetic resonance imaging (MRI) scan of the shoulder isn't necessary to diagnose frozen shoulder, but your doctor may suggest an MRI scan to exclude other structural shoulder problems.

Most treatments for frozen shoulder involve moving and stretching the shoulder muscles — just the opposite of what most people do when their shoulder begins to hurt and stiffen.

Your doctor may recommend you see a physical therapist. He or she can show you how to maintain as much mobility in your shoulder as possible, without stressing your shoulder to the point of causing a lot of pain. Continue to use the involved shoulder and extremity in as many daily life activities as possible within the limits of your pain and range of motion constraints.

Gently and gradually stretching your shoulder muscles may not completely alleviate the symptoms of frozen shoulder. However, it may help restore enough flexibility to enable you to resume your everyday activities.

Your doctor may also recommend these treatments:

Newer treatment options include injecting fluid into the shoulder joint to expand the shoulder capsule and break up adhesions. Doctors still need to assess the long-term results of this treatment.

Maintaining as much range of motion as possible in your shoulder is important. Your physical therapist can show you how to move your shoulder joint through comfortable range of motion planes to avoid further stiffening.

Once pain has lessened, you may be able to tolerate more shoulder exercises. As you progress into the thawing phase, your physical therapist can advance your stretching and strengthening program to maximize your shoulder's range of motion and function.

Acupuncture has been used effectively in some people with frozen shoulder to provide pain relief. This medical treatment, originally developed in China, has been in use for more than 2,500 years.

It involves inserting extremely fine needles in your skin to stimulate specific points that allow the free flow of energy in your body. Depending on the problem being treated and the type of acupuncture, a practitioner may use a number of needles or just a few. Typically, the needles remain in place for 15 to 40 minutes. During that time they may be moved or manipulated. Because the needles are hair thin and flexible and are generally inserted superficially, most acupuncture treatments are relatively painless.