Frozen Shoulder
Adhesive capsulitis causing progressive painful restriction of shoulder movement in all planes. Strongly associated with diabetes (~20% of diabetics affected). Self-limiting over 1–3 years.
Key Facts
Global restriction of shoulder movement: both active AND passive movement equally affected (especially external rotation) Three phases: freezing (painful, 2–9 months), frozen (stiff, 4–12 months), thawing (gradual recovery, 5–24 months) Diabetes mellitus: strongest risk factor (~20% of diabetics; bilateral in ~40%; often more severe and prolonged) Self-limiting: most resolve within 1–3 years; ~40% have residual mild limitation Treatment: analgesia + physiotherapy; intra-articular corticosteroid injection (most effective in freezing phase) Diagnosis: clinical — no specific blood test; X-ray/MRI usually normal (MRI may show capsular thickening) Age: 40–60 years; female > male; rare under 40 Other associations: thyroid disease, cardiac surgery, cervical disc disease, Dupuytren contracture
Overview
Key Facts
Frozen shoulder (adhesive capsulitis) is characterised by progressive pain and stiffness of the glenohumeral joint, with restriction of both active and passive range of movement in all planes.
Epidemiology
- Prevalence: ~2–5% of general population
- Age: 40–60 years
- Female > male
- Diabetes: ~20% affected (bilateral in ~40%)
Aetiology
- Idiopathic (most common)
- Diabetes mellitus (strongest risk factor)
- Thyroid disease
- Post-surgery/immobilisation
- Dupuytren disease
Pathophysiology
- Chronic inflammation and fibrosis of the glenohumeral joint capsule
- Capsular thickening and contracture → loss of joint volume
- Rotator interval and inferior capsule particularly affected
- Inflammatory cytokines (IL-1, IL-6, TNF-α) → fibrosis → adhesions
- External rotation restricted first (capsular pattern)
Clinical Presentation
Freezing Phase (2–9 months)
- Gradually increasing shoulder pain (often severe)
- Pain at rest and at night
- Increasing stiffness
- Progressive loss of movement
Frozen Phase (4–12 months)
- Stiffness dominant; pain may lessen somewhat
- Marked restriction of movement in all planes
- External rotation most limited
- Difficulty with ADLs (dressing, reaching behind back)
Thawing Phase (5–24 months)
- Gradual return of movement
- Pain resolves
- ~40% have mild residual limitation
Key Examination Findings
- Global restriction of both active AND passive ROM (hallmark)
- External rotation most restricted (capsular pattern)
- No weakness (unless disuse atrophy)
Red Flags
- Weakness (rotator cuff tear)
- Deformity (dislocation)
- Systemic features (infection, malignancy)
- Failure to improve by 18 months
Differential Diagnosis
| Diagnosis | Key Features | Investigation |
|---|---|---|
| Rotator cuff tear | Active ROM restricted, passive preserved; weakness | USS/MRI |
| Subacromial impingement | Painful arc 60–120°, passive ROM preserved | USS, Neer/Hawkins test |
| Glenohumeral OA | Older patients, crepitus, osteophytes on X-ray | X-ray |
| Cervical radiculopathy | Neck pain, dermatomal distribution, neurological signs | MRI spine |
| Calcific tendinopathy | Acute severe pain, calcification on X-ray | X-ray, USS |
Diagnosis / Investigation
Clinical Diagnosis (investigations mainly to exclude alternative diagnoses)
- X-ray: usually normal; excludes OA, calcific tendinopathy, tumour
- MRI: capsular thickening at rotator interval; often not required for diagnosis
- USS: excludes rotator cuff tear
Bloods
- HbA1c/fasting glucose: screen for diabetes
- TFTs: screen for thyroid disease
Management
Non-pharmacological
- Patient education: reassurance about self-limiting nature
- Physiotherapy: gentle stretching within pain limits; avoid aggressive mobilisation in freezing phase
- Home exercise programme: pendular exercises, wall climbing
Pharmacological
- Analgesia: paracetamol, NSAIDs (ibuprofen 400mg TDS, naproxen 500mg BD)
- Intra-articular corticosteroid injection: most effective in freezing phase; improves pain and ROM short-term
- Triamcinolone 40mg + lidocaine into glenohumeral joint
- Up to 3 injections
Surgical/Interventional
- Hydrodilatation: injection of saline + steroid to stretch capsule (distension arthrography)
- Manipulation under anaesthesia (MUA): for severe persistent stiffness
- Arthroscopic capsular release: for refractory cases (>12 months)
Referral Criteria
- Physiotherapy: first-line
- Orthopaedics/shoulder specialist: no improvement after 6 months conservative treatment
- Diabetology: optimise glycaemic control
Prognosis
- Self-limiting: ~90% resolve within 1–3 years
- ~40% have mild residual restriction (usually not functionally significant)
- Diabetic patients: often more severe, prolonged, and bilateral; may not fully resolve
- Recurrence: ~6–17%; extremely rare in same shoulder
- Corticosteroid injection: effective in ~60–70% for pain relief (freezing phase)
- MUA/surgery: reserved for refractory; ~85–90% good outcomes
Other Relevant Information
Three Phases Summary
| Phase | Duration | Features |
|---|---|---|
| Freezing | 2–9 months | Increasing pain → stiffness |
| Frozen | 4–12 months | Stiffness dominant, pain settles |
| Thawing | 5–24 months | Gradual return of movement |