Frozen shoulder

Definition

Frozen shoulder, also known as adhesive capsulitis, is a condition characterized by stiffness and pain in your shoulder joint. As the condition worsens, your shoulder’s range of motion becomes markedly reduced. Frozen shoulder usually affects one shoulder at a time, although some people may eventually develop frozen shoulder in the opposite shoulder.

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

Symptoms

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

  • Painful stage. During this stage, pain occurs with any movement of your shoulder and your shoulder’s range of motion starts to become limited.
  • Frozen stage. Pain may begin to diminish during this stage. However, your shoulder becomes stiffer and your range of motion decreases notably. Avoid extreme movements that cause pain during this stage. But, you can and should continue normal use of your shoulder.
  • Thawing stage. During the thawing stage, the range of motion in your shoulder begins to improve.

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

 

Causes

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 capsule and connective tissue 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.

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 decrease. As a result, pain and subsequent loss of movement may occur. In some cases, mobility may decrease so much 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.

Risk factors

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

  • Age. People 40 and older are more likely to experience frozen shoulder.
  • Diabetes. For unknown reasons, frozen shoulder is more common in people with diabetes.
  • Immobility. People who have experienced prolonged immobility of their shoulder — perhaps due to trauma, overuse injuries or surgery — are at higher risk of developing frozen shoulder.
  • Systemic diseases. People with a systemic disease, such as an overactive thyroid (hyperthyroidism), underactive thyroid (hypothyroidism), cardiovascular disease or Parkinson’s disease, may experience frozen shoulder.

When to seek medical advice

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

Tests and diagnosis

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.

Treatments and drugs

Most frozen shoulder treatment involves controlling shoulder pain and preserving as much range of motion in the shoulder as possible to permit you to perform everyday tasks.

Your doctor may recommend that 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 moving your shoulder through range of motion exercises won’t completely alleviate the symptoms of frozen shoulder. However, it may help restore enough shoulder motion to enable you to resume your everyday activities.

Your doctor may also recommend these treatments:

  • Nonsteroidal anti-inflammatory drugs (NSAIDs). These medications may help relieve pain and inflammation associated with frozen shoulder. Acetaminophen (Tylenol, others) also may be effective for pain relief.
  • Heat or cold. Applying heat or cold to your shoulder can help relieve pain.
  • Corticosteroids. Injecting these anti-inflammatory hormones into your shoulder joint may help decrease pain and shorten symptom duration during the initial painful phase. Repeated corticosteroid injections aren’t recommended.
  • Surgery. In a small number of cases, especially if your symptoms don’t improve despite other measures, surgery may be an option to remove scar tissue and adhesions from inside your shoulder joint. Doctors usually perform this surgery with a lighted, tubular instrument inserted through an incision in your joint (arthroscopically).
  • Shoulder manipulation. In a few people, if severe stiffness persists, gently manipulating the shoulder during a general anesthetic may help to improve motion.
  • Electrical stimulation. Transcutaneous electrical nerve stimulation (TENS) is a treatment that can be used to help control your pain. In this procedure, a tiny electrical current is delivered to key points on a nerve pathway. The current, delivered through electrodes taped to your skin, isn’t painful or harmful. It’s not known exactly how TENS works, but it’s thought that it might stimulate the release of pain-inhibiting molecules (endorphins) or block pain fibers that carry pain impulses.

Lifestyle and home remedies

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.