Frozen shoulder: why the joint locks up, and how physiotherapy restores movement

Despite its name, frozen shoulder has nothing to do with cold weather. The term describes a joint capsule that has thickened and tightened around itself, gradually locking the shoulder into a smaller and smaller range of motion.

It is also far slower to resolve than most shoulder problems. However, with the right physiotherapy approach at the right stage, that timeline can be shortened considerably.

In this guide, you'll find:

• The most common causes of frozen shoulder
• What's actually happening inside the joint capsule, with a deeper-dive option
• How we diagnose the root cause at Physio Flora
• Our physiotherapy treatment options for frozen shoulder
• Three physiotherapist-approved exercises to start today
• Answers to the questions our patients ask most

What is frozen shoulder?

Frozen shoulder, also called adhesive capsulitis, is a progressive loss of movement in the shoulder joint. Unlike a rotator cuff strain, it restricts both active and passive movement equally. This means even a physiotherapist moving your arm for you cannot fully replicate its normal range.

The condition typically develops in three overlapping phases. The freezing phase brings increasing pain and a gradual loss of motion. The frozen phase brings less pain but significant stiffness. The thawing phase brings a slow, often uneven, return of movement.

Left untreated, this full cycle can take one to three years. Therefore, most patients seek treatment specifically to shorten that timeline and manage pain along the way.

Deep dive

Go deeper: the tissue science

This section goes deeper into the physiology for readers who want it. Skip ahead to "Common causes of frozen shoulder" if you'd rather get straight to the practical guidance.

The shoulder joint is surrounded by a capsule, a sleeve of connective tissue that normally sits loose enough to allow a huge range of motion. In frozen shoulder, this capsule becomes inflamed and then fibrotic, meaning it thickens with disorganised collagen and loses its natural elasticity.

Adhesions can also form between layers of the capsule itself, particularly in a pouch at the bottom called the axillary recess. Because this recess needs to unfold for the arm to lift overhead, adhesions here explain much of the classic loss of external rotation and abduction seen in this condition.

Healing does not follow the muscle or tendon timeline most people expect. The inflammatory freezing phase can last two to nine months. The frozen phase, where the capsule is maximally thickened and stiff, typically runs another four to twelve months. The thawing phase, as the capsule gradually remodels and loosens, can take a further six months to two years.

This is markedly longer than muscle or ligament healing, because capsular tissue remodels slowly and inconsistently. Diabetic patients, in particular, tend to move through these phases more slowly, due to how elevated blood sugar affects collagen cross-linking within the capsule.

Common causes of frozen shoulder

Several patterns show up again and again in the clinic:

Prolonged immobilisation. A shoulder kept still after surgery, a fracture, or a rotator cuff injury has a much higher chance of developing secondary capsular stiffness.

Diabetes. People with diabetes are up to five times more likely to develop frozen shoulder, and it often affects both shoulders over time.

Thyroid disorders. Both an underactive and an overactive thyroid are linked to a higher risk of capsular thickening.

Age and sex. The condition most often appears between ages 40 and 60, and it affects women more frequently than men.

No identifiable cause. In many cases, frozen shoulder develops without any preceding injury, which can be frustrating for patients looking for an explanation.

Because the underlying driver varies so much between patients, treatment needs to account for each person's specific risk profile and current phase.

How we diagnose the root cause at Physio Flora

Diagnosis starts with distinguishing frozen shoulder from rotator cuff impingement, since the two are often confused but treated very differently. The key test is comparing active and passive range of motion. In frozen shoulder, both are restricted by a similar amount, whereas rotator cuff problems usually preserve more passive movement.

We also assess which phase you are in, since this changes the entire treatment plan. A joint that is still acutely inflamed needs a very different approach to one that is simply stiff and ready for aggressive mobilisation.

External rotation is typically the most restricted movement, followed by abduction and then internal rotation. This specific pattern, known as a capsular pattern, is one of the clearest diagnostic markers we look for during assessment.

Physiotherapy treatment options for frozen shoulder

Treatment is matched to your current phase, then progressed as the capsule loosens.

Manual therapy and Mulligan mobilisation. Mobilisation with movement techniques help restore glide within the joint and are particularly effective for addressing the positional restrictions that build up in the capsule.

Dry needling. Targets the protective guarding that develops in the deltoid, rotator cuff, and upper trapezius as the shoulder compensates for lost range.

Phase-specific stretching programme. Gentle, pain-guided mobility work during the freezing phase, progressing to sustained end-range stretching once the joint reaches the frozen and thawing phases.

Progressive strengthening. Once range of motion improves, rotator cuff and scapular strengthening rebuilds control through the newly regained movement.

Sports performance coaching. For golfers, tennis and padel players, we retrain overhead and rotational mechanics so the shoulder returns to sport with proper movement patterns rather than compensations picked up during the stiff phase.

Most patients notice a meaningful change in daily function within four to six weeks, although full range of motion typically takes several months to fully restore.

Three physiotherapist-approved exercises to start today

These are safe starting points for most stages of frozen shoulder. However, a phase-specific assessment ensures you are neither under-loading a joint ready for progress nor aggravating one still acutely inflamed.

Pendulum swings. Lean forward, letting your affected arm hang freely, then gently swing it in small circles using your body's momentum rather than your shoulder muscles. This is well tolerated even during the painful freezing phase.

Stick-assisted external rotation. Hold a broomstick horizontally with both hands, elbows bent at your sides, and use your unaffected arm to gently rotate the stick outward. Stop at the first point of resistance, not pain.

Wall crawl. Face a wall and walk your fingers upward as far as comfortable, then slowly walk them back down. Repeat, aiming for a small improvement in height each week.

If an exercise sharply increases pain rather than producing mild stretch discomfort, stop and book an assessment rather than pushing through it.

Answers to the questions our patients ask most

How long does frozen shoulder actually last?

Untreated, the full cycle often runs one to three years. However, structured physiotherapy at the correct phase frequently shortens this considerably and improves comfort throughout.

Can frozen shoulder come back in the other shoulder?

Yes. Around 1 in 6 people who develop frozen shoulder in one shoulder will later develop it in the other, particularly if diabetes or a thyroid condition is present.

Do I need a cortisone injection?

Not always. Injections can reduce inflammation and pain during the freezing phase, which may make physiotherapy more effective. However, they do not address the capsular stiffness itself, so movement work remains essential.

Will it go away on its own without treatment?

Often, yes, eventually. However, "eventually" can mean years of restricted movement and lost function, which is why most patients choose to actively treat it instead.

Frozen shoulder can feel indefinite while you are in it, but it is not permanent.

At Physio Flora, we combine thorough clinical assessment with evidence-based treatment and a genuine understanding of an active lifestyle, wherever it's lived. No referral needed. Consultations available in English, Dutch, German and Spanish. Same-week appointments available.

Your shoulder was built to move freely. Let's get it back there, one phase at a time.

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Physio Flora · English, Dutch, German and Spanish-speaking physiotherapy on the Costa del Sol · Specialising in manual therapy and Mulligan mobilisation for joint stiffness and capsular conditions