Frozen Shoulder (Adhesive Capsulitis)

Learn about the three stages of frozen shoulder, who is at risk, and which treatments can relieve pain and speed up recovery.

What is it?

• The medical name is “adhesive capsulitis.” Your shoulder joint is wrapped in a thin sleeve of tissue called the joint capsule — think of it as a bag around the joint.
• In frozen shoulder, this bag becomes inflamed, thick, and tight. The shoulder becomes painful and stiff in every direction.
• It is most common between ages 40 and 60, which is why it is nicknamed “fifty-year shoulder” in Taiwan — but it is not limited to people in their fifties.
• The condition usually moves through three stages, and the whole course often lasts 1 to 3 years:
  • Freezing stage: about 2 to 9 months. Pain is the main problem, often worse at night and disturbing sleep.
  • Frozen stage: about 4 to 12 months. Pain slowly eases, but the shoulder becomes very stiff — combing your hair, fastening a bra, or reaching a high shelf becomes difficult.
  • Thawing stage: about 6 months to 2 years. Movement gradually returns.
• Most people improve substantially with time, but recent research shows it does not always resolve completely on its own — about 4 in 10 people still have some symptoms at 4 years. So active treatment is recommended rather than simply toughing it out.

Common symptoms

• A deep, aching shoulder pain that comes on gradually, usually without an injury.
• Marked night pain — sleeping on the affected side may wake you up.
• Stiffness in every direction of movement:
  • Trouble raising the arm overhead
  • Trouble reaching behind the back (fastening a bra, reaching a back pocket)
  • Rotating the arm outward (external rotation) is especially limited — for example, washing or combing your hair
• The shoulder is stiff even when someone else tries to move it for you. This is a key difference from tendon problems.
• Usually only one shoulder is affected, though a minority of people later develop it on the other side.

Why does it happen? (Risk factors)

The exact cause is not fully understood, but the risk is higher in these groups:

• Diabetes: the strongest known link. People with diabetes develop frozen shoulder much more often, and their course may last longer.
• Thyroid disease: both an overactive and an underactive thyroid are associated with frozen shoulder.
• Age and sex: most common between 40 and 60; women are affected slightly more often than men.
• Prolonged immobility: keeping the shoulder still for a long time after an injury or surgery (for example, breast or heart surgery).
• Other conditions: stroke, Parkinson’s disease, or a previous frozen shoulder (the other side is then at higher risk).

How is it diagnosed?

• The history and physical exam are key. Your doctor will ask you to move the arm in different directions, and will also move it for you (passive movement).
  • The hallmark of frozen shoulder is stiffness with both active and passive movement, in all directions, with external rotation most restricted.
  • If you cannot lift the arm yourself but someone else can lift it for you, the problem is more likely the rotator cuff (the group of tendons around the shoulder), not frozen shoulder.
• X-ray: usually normal in frozen shoulder. It is done mainly to rule out arthritis, calcific tendinitis, or other bone problems.
• Ultrasound or MRI: not needed for everyone. These are mainly used to rule out other diagnoses such as a rotator cuff tear.
• Your doctor may also order blood tests for blood sugar or thyroid function, since both conditions are closely linked to frozen shoulder.

Treatment and self-care

The general principle: control pain first in the early stage, then focus on restoring movement.

• Oral pain relievers: non-steroidal anti-inflammatory drugs (NSAIDs) can ease pain in the short term.
• Corticosteroid injection into the joint:
  • When given early (in the freezing stage), there is good evidence that it relieves pain and speeds up recovery.
  • It is often done under ultrasound guidance so the medicine reaches the joint accurately.
  • If you have diabetes, your blood sugar may rise temporarily for a few days after the injection — monitor it more closely during that time.
• Hydrodilatation (joint distension):
  • Sterile fluid (sometimes with a steroid) is injected into the joint to stretch the tightened capsule from the inside.
  • Studies comparing the different treatments rank this among the most effective non-surgical options for relieving pain and restoring movement — usually more effective than a steroid injection alone — and it is often followed by physiotherapy.
• Physiotherapy and home exercises:
  • The key rule: stretch and move within a tolerable level of pain — do not force through sharp pain.
  • In the painful stage, gentle pendulum swings are enough; in the frozen and thawing stages, gradually increase the stretching.
  • Common exercises: wall climbing with the fingers, towel stretch behind the back, doorway stretch.
• Hyaluronic acid injections: the evidence is mixed; not a first-line treatment, but worth discussing with your doctor.
• Procedures — reserved for stubborn cases only:
  • Usually considered when severe stiffness persists despite about 9 to 12 months of non-surgical treatment.
  • Manipulation under anesthesia: while you are asleep, the doctor moves the shoulder to stretch open the tight capsule.
  • Arthroscopic capsular release: keyhole surgery that cuts and releases the tightened capsule.
  • A large clinical trial found that, compared with promptly started structured physiotherapy, neither procedure gave clearly better overall results at one year — so there is no need to rush into surgery.

Self-care tips:

• Do not stop moving the shoulder entirely because of pain — complete rest makes stiffness worse.
• Do not force aggressive stretches either — severe pain can worsen the inflammation.
• Heat before exercise can help relax the tissue; brief icing may help during flares of sharp pain.
• Good control of blood sugar and thyroid disease supports recovery.

When to seek medical care — red flags

See a doctor promptly if any of the following applies, because the problem may not be a simple frozen shoulder:

• A history of cancer, with shoulder pain that keeps worsening or night pain that prevents sleep
• Fever or chills, or a shoulder that is red, hot, and swollen (infection must be ruled out)
• A deformed shoulder after an injury, or inability to move it at all (fracture or dislocation must be ruled out)
• Rapidly worsening arm weakness, or numbness and tingling in the arm or hand

Frequently asked questions

Q: Will it heal on its own? A: Most cases improve with time, but the natural course often takes 1 to 3 years, and it does not always resolve completely — research shows about 4 in 10 people still have some symptoms at 4 years. Early treatment — especially a steroid injection into the joint combined with exercise therapy — can shorten the painful period and speed recovery, so there is no need to simply tough it out.

Q: When I stretch, is more pain better? A: No. The right approach is to stretch to a point of firm tightness that you can tolerate — some aching is fine, but sharp pain is not. Forcing through severe pain can worsen the inflammation, make nights more painful, and actually slow your progress.

Q: I’m only 35 — why did I get “fifty-year shoulder”? A: The nickname is just a nickname. Frozen shoulder can occur under 40, especially in people with diabetes, thyroid disease, or a shoulder that was kept still for a long time after injury or surgery. When it appears at a younger age, doctors often check blood sugar and thyroid function.

Q: How is frozen shoulder different from a rotator cuff injury? A: Frozen shoulder is stiff in every direction — the arm is restricted whether you move it yourself or someone moves it for you, and external rotation is especially tight. Rotator cuff problems typically cause pain or weakness at certain angles, but the arm can usually be lifted when someone assists. The treatments differ, so an examination by a doctor is the most reliable way to tell them apart.