What frozen shoulder is
Adhesive capsulitis, known almost universally as frozen shoulder, is a condition in which the capsule surrounding the shoulder joint becomes inflamed, thickened and then contracted. The joint physically loses its range as the capsule tightens around it.
The defining feature is loss of passive external rotation, meaning the movement is restricted even when someone else moves your arm and your own muscles are doing nothing. That is what separates it from a rotator cuff problem, where passive movement usually stays close to full while active movement hurts.
It affects roughly 2 to 5 per cent of the population, most commonly between 40 and 60, and more often women. Diabetes raises the risk substantially, with prevalence in people with diabetes reported at around 10 to 20 per cent, and those cases tend to be more stubborn.
What causes it
Primary frozen shoulder arrives without an obvious trigger, which is a large part of what makes it so frustrating. Secondary frozen shoulder follows a period of immobilisation: a fracture, surgery, or several weeks of protecting a sore shoulder by not moving it.
The underlying process involves inflammatory change in the capsule followed by fibrosis, with the rotator interval and the coracohumeral ligament tightening particularly. That specific pattern explains why external rotation is usually lost first and recovers last.
What raises the risk
- Diabetes, both type 1 and type 2, which is the strongest known association
- Thyroid disease, particularly hypothyroidism
- A period of shoulder immobilisation after injury or surgery
- Age between 40 and 60
- A previous frozen shoulder on the other side, which happens in around one in five people
- Dupuytren's contracture, which shares a fibrotic tendency
The single most useful clinical test is passive external rotation with the elbow at the side. If someone else rotating your arm outward is blocked well short of normal and produces pain at the end point, that is capsular restriction. If passive rotation is close to full and the pain comes on when you lift the arm yourself, the problem is far more likely to be the rotator cuff. Getting this distinction right changes the whole plan, because a cuff protocol applied to a frozen shoulder in the freezing phase makes it considerably more painful.
What the evidence says
The condition is self-limiting in most cases, and the timeline is long. Published series report an average of around 30 months to resolution, with a meaningful minority left with some residual restriction that rarely limits daily function.
Intra-articular corticosteroid injection has the best evidence of anything available for the painful freezing phase, producing significant pain relief and improved range at six weeks, with the advantage narrowing over the following months. Combining an injection with physiotherapy outperforms either alone.
Hydrodilatation, where fluid is injected under pressure to distend the capsule, has reasonable evidence in the frozen phase and is a reasonable next step when an injection alone has not restored range.
Physiotherapy intensity should follow the phase. Trials comparing intensive stretching with gentler pain-guided mobilisation in the painful phase favour the gentler approach on both pain and eventual range. In the frozen and thawing phases, that reverses and sustained end-range stretching becomes the main driver of progress.
Recovery timeline
Freezing, roughly 2 to 9 months: pain dominates, is often worse at night, and range is progressively lost. Frozen, roughly 4 to 12 months: pain settles considerably while stiffness is at its worst. Thawing, roughly 5 to 24 months: range gradually returns.
These phases overlap and the ranges are wide, which is honest rather than evasive. What can be said with more confidence is the direction: the pain phase ends well before the stiffness does, and almost everyone gets the majority of their function back.
| Stage | ✓ Do this | ✗ Avoid this |
|---|---|---|
| Freezing (painful) | Gentle pain-free range work, pendulum exercises, heat, sleep positioning. Discuss a steroid injection with your GP early. | Aggressive end-range stretching, or working through sharp pain |
| Frozen (stiff) | Sustained end-range stretching, joint mobilisation, hands-on capsular work. Longer holds, more often. | Backing off because it feels tight; tightness without sharp pain is the target here |
| Thawing | Progressive strengthening through the regained range, return to overhead loading. | Stopping the range work the moment daily tasks feel easy |
| Throughout | Keep the other shoulder and the whole body moving. Check HbA1c if you have not recently. | Complete rest of the arm, which accelerates the stiffness |
How we treat it at Kingsway
What treatment looks like here
The first session establishes which phase you are in, because that determines whether we are aiming to settle pain or to win range back.
- Passive and active range measurement in all directions, recorded so progress is objective
- Joint mobilisation graded to the phase, from gentle oscillation to sustained end-range glides
- Soft tissue release for the secondary tightness that develops through the neck, upper trapezius and pec minor
- Acupuncture or dry needling for pain relief in the freezing phase, particularly for night pain
- Therapeutic ultrasound over the anterior capsule where pain limits hands-on work
- A home stretching programme with specific hold times, adjusted at every review
This is a long condition, and treatment is spread out to match. Weekly sessions during a bad freezing phase, then every two to three weeks through the frozen and thawing phases, is a common pattern. Because it typically runs over a year, the ten or twenty session package usually works out considerably cheaper than paying per visit.
When to get it checked
Get a shoulder assessed if it has been stiffening progressively over weeks, if you cannot reach behind your back or across your body, or if night pain is disturbing your sleep. Early identification matters here, because the freezing phase is the window where an injection makes the biggest difference.
See a doctor or go to A&E if
- Shoulder stiffness following a fall or an obvious injury, which needs imaging to exclude a fracture or dislocation
- A visible change in the shape of the shoulder or an inability to lift the arm at all
- Fever, redness or heat over the joint
- Unexplained weight loss or a history of cancer alongside new shoulder pain
- Pain that is constant, severe and entirely unaffected by position or activity
Common questions
How long will this take?
Published averages sit at around 30 months from first symptom to resolution, with wide variation. Many people are functionally comfortable well before full range returns.
Diabetes tends to lengthen the course. Getting an injection early in the painful phase and staying consistent with range work through the stiff phase are the two things most under your control.
Should I push through the pain when stretching?
It depends on the phase. In the painful freezing phase, working into sharp pain tends to increase inflammation and slow progress, so stretching stays within a comfortable range.
In the frozen and thawing phases, a strong stretching sensation held at end range is the treatment, and progress is slow without it.
Is surgery ever needed?
Occasionally. Manipulation under anaesthetic or arthroscopic capsular release are considered when someone has been through the freezing phase, has a well-established stiff shoulder, and has not responded to several months of proper conservative treatment plus injection.
Both need committed physiotherapy afterwards to hold the range gained.
Will it happen to the other shoulder?
It happens on the other side in around one in five people, usually within five years. It rarely recurs in the same shoulder once it has fully resolved.
If you are diabetic, keeping glycaemic control tight is the most useful preventive step available.