What it actually is
In a frozen shoulder — adhesive capsulitis — the capsule surrounding the shoulder joint becomes inflamed and then thickens and contracts. The joint physically loses room to move.
This is the distinguishing feature. With most shoulder problems you can move the arm further yourself, or someone can move it for you, even if it hurts. With a true frozen shoulder the restriction is in the joint itself, so the movement is not available in either direction. That is what a physiotherapist is testing for.
It is more common between roughly 40 and 60, more common in women, and notably more common in people with diabetes or thyroid disorders. It often arrives without any injury at all.
The three stages
- 1
Freezing — roughly 2 to 9 months
Pain dominates. It builds gradually, is often worse at night, and sleeping on that side becomes impossible. Movement is reducing, but pain is the main complaint. This is when most people first seek help.
- 2
Frozen — roughly 4 to 12 months
The pain settles noticeably, but stiffness is now the problem. Reaching behind your back, fastening clothing, or reaching a high shelf become difficult or impossible. Many people find this stage more disabling day to day, even though it hurts less.
- 3
Thawing — roughly 5 to 24 months
Movement gradually returns. This is usually slow and uneven — good weeks and flat weeks — but it is genuinely a recovery phase.
Why the stage changes the treatment
This is the part that most affects how people do, and it is where well-meant advice often goes wrong.
During the freezing stage the capsule is inflamed and irritable. Aggressive stretching here tends to increase pain and night symptoms without improving range, and it can make the whole episode harder. Treatment should focus on settling pain, protecting sleep, and keeping the movement you still have.
During the frozen stage the tissue is no longer acutely inflamed but is genuinely tight. This is when sustained, progressive stretching and hands-on mobilisation earn their place — and when working steadily matters.
During thawing, the job is to regain full range and rebuild strength in a shoulder that has not worked properly for the better part of a year.
The honest timeline
Frozen shoulder is self-limiting for most people — it does resolve. But the full cycle commonly runs one to three years, and a proportion of people are left with some lasting restriction.
That is why the goal of treatment is rarely "cure it faster" in the freezing stage. It is to keep you functioning, protect your sleep, preserve as much movement as possible, and then work hard at the point where hard work actually pays off.
Steroid injection in the painful early stage, arranged through your doctor, helps many people and can make physiotherapy more productive. It is worth discussing if pain is dominating.
What to expect from an assessment
A physiotherapist will check whether the restriction really is capsular, rule out other causes of a stiff painful shoulder, and work out your stage. From there you should get a plan matched to that stage, a realistic timeline, and something to do at home — because home consistency drives most of the outcome in this condition.
In short
- The restriction is in the joint capsule, not in the muscles.
- Treatment should match the stage — the same exercise can help or harm.
- Aggressive stretching during the painful stage usually backfires.
- The full cycle commonly takes one to three years.
See a doctor first if you have
- Shoulder stiffness following a significant injury or fall
- The shoulder looks visibly deformed, or you cannot move it at all after trauma
- Fever, or a hot and swollen joint
- Unexplained weight loss alongside shoulder pain
- Numbness, pins and needles, or weakness in the arm or hand
This article is general information, not a diagnosis. If any of these apply to you, please get medical advice before starting exercise or physiotherapy.
