Frozen shoulder, properly called adhesive capsulitis, is one of the few musculoskeletal conditions with a genuinely predictable course. The capsule surrounding the shoulder joint becomes inflamed, thickens, and progressively tightens, restricting movement in a characteristic pattern.
It is also one of the most commonly mistreated, because the right approach in one stage is actively counterproductive in another.
How to recognise it
The hallmark is loss of passive external rotation. If someone else gently rotates your relaxed arm outward and it stops early, and hurts, that points strongly to the capsule rather than a tendon.
Other typical features:
- Pain on the outer upper arm, often worse at night and when lying on that side
- Difficulty reaching behind your back, into a sleeve, or up to a high shelf
- Onset without any clear injury
- Most common between ages 40 and 60
It is markedly more common in people with diabetes or thyroid disorders, and can follow a period of shoulder immobilisation after injury or surgery.
The three stages
| Stage | Duration | What dominates |
|---|---|---|
| 1. Freezing | 2–9 months | Pain. Movement shrinking steadily. Night pain at its worst |
| 2. Frozen | 4–12 months | Stiffness. Pain settles, but range stays restricted |
| 3. Thawing | 5–24 months | Movement gradually returns |
Total recovery commonly runs one to three years. That is a hard thing to hear, and it is why an honest conversation early matters more than optimistic promises.
Why the stage changes the treatment
This is the single most useful thing to understand about the condition.
During the freezing stage, the capsule is inflamed and highly irritable. Aggressive stretching genuinely makes it worse, it provokes more inflammation and more guarding. The priorities here are pain control, sleep, and gentle movement within a comfortable range. Pendulum exercises and light range-of-motion work are appropriate; forcing end-range is not.
If a stretch leaves the shoulder aching for more than a couple of hours afterwards, it was too much for the stage you are in.
During the frozen stage, inflammation has largely calmed and stiffness is the limiting factor. Now sustained, progressive stretching is exactly right, and gentle end-range work is what restores capsular length.
During thawing, the emphasis shifts to strengthening and returning to full functional use, since months of restriction leave the rotator cuff and scapular muscles deconditioned.
What the evidence supports
- Physiotherapy matched to stage: the mainstay, and effective for restoring range
- Corticosteroid injection: most useful in the painful freezing stage, where it can meaningfully reduce pain and allow rehabilitation to progress
- Hydrodilatation: distending the capsule with fluid; helpful for some in the frozen stage
- Surgery: reserved for the minority who remain significantly restricted after a long course of conservative treatment
Manipulation under anaesthetic and surgical release are effective but are genuinely last resorts, given that most cases resolve without them.
What you can do daily
Little and often beats one long session. Four to five short bouts a day of gentle range work, pendulums, table slides, wall walks, assisted external rotation with a stick, outperforms a single aggressive stretch.
Warmth before exercise helps. A hot shower or heat pack for ten minutes makes the capsule more compliant and the session more comfortable.
When to get assessed
Early. The most common regret we hear is waiting six months in the hope it would resolve on its own, because the freezing stage is where pain control and appropriate loading make the biggest difference to how the whole course feels.
Get it looked at promptly if you cannot lift your arm at all after an injury, if there is significant weakness rather than just stiffness, or if you have had a fall, those suggest a different problem, such as a rotator cuff tear, that is managed quite differently.