Frozen Shoulder

Adhesive Capsulitis

Definition

  • Idiopathic inflammatory condition characterized by progressive shoulder pain & stiffness that spontaneously resolves
  • Restriction of GHJ movement in all planes

Epidemiology

  • 40-60 years
  • Women 2:1
  • Non-dominant limb more affected
  • Bilateral in 10-40%
  • 2% of population
  • 11% of diabetic population
  • Sedentary workers ↑

Aetiology

  • Poorly understood
  • Autoimmune theory proposed but not proven

Predisposing factors

  • Immobility
  • Trauma (often trivial)
  • Cervical disc disease
  • Diabetes Mellitus
    • 10-20% compared with 2% of general population
    • Bilaterality ↑ (40%)
    • > 10 years of IDDM ↑ risk
  • Thyroid disorders
    • Hyperthyroidism
    • Resolves with treatment of disease
  • Myocardial infarction
  • Intrathoracic disorders
    • TB
    • Carcinoma
    • Emphysema
  • Intracranial Pathology
    • Hemiplegia
    • Cerebral Haemorrhage
    • Cerebral tumours
  • Personality disorder

Not associated with

  • Osteoarthritis
  • Cuff Pathology

Classification

Lunberg

  • Primary
  • Secondary

Apley

Three phases each lasting 4-8 months

  1. Freezing
    • Increasing pain
  2. Frozen
    • Decreasing pain
    • Increasing stiffness
  3. Thawing
    • Decreasing stiffness

Pathogenesis & Pathology

Initial synovitis of unknown cause

  • Results in
    • Capsulitis
    • Intra-articular adhesions
    • Obliteration of inferior axillary fold
  • Subsequent development of
    • Subacromial adhesions
    • Rotator cuff contracture
    • Then spontaneous resolution
  • Contracted, thickened joint capsule drawn tightly around the humeral head with relative lack of synovial fluid
  • See cellular changes of inflammation with fibrosis & perivascular infiltration in subsynovial layer of capsule (Nevaiser) – similar appearance to Dupuytren’s disease
  • Poor correlation between the microscopic & gross capsular changes
  • Capsular folds & pouches obliterated by synovial adhesions
  • Coracohumeral ligament is shortened & prevents ER
  • Rotator cuff bellies contracted fixed & inelastic
  • Few adhesions in subacromial bursa
  • Spontaneous resolution the rule

Three classical stages (Apley)

Freezing Phase

  • Gradual diffuse onset shoulder pain
  • Lateral to arm at deltoid insertion
  • Worse at night & lying on that side
  • If reduce movement the pain reduced
  • Duration variable 2-9 months

Frozen Phase

  • Slowly progressive loss of shoulder movement with gradual subsidence of pain
  • Affects ADLs usually
  • Usually characteristic loss of ER & Abduction
  • 10% have negligible glenohumeral movement
  • Duration 4-12 months

Thawing Phase

  • Gradually regain shoulder movement
  • Slow ↑ in movement with loss of discomfort
  • 6-9 months to regain functional ROM

Clinical Features

History

  • Insidious onset
  • No history of trauma

Pain

  • Initially
    • At site of deltoid insertion
    • At extremes of motion
  • Becomes more
    • Diffuse
    • Severe
    • Constant
    • Interferes with sleep
  • Then begins to decrease
    • Rest pain disappears
    • Pain only on movement

Stiffness

  • Develops after onset of pain
  • Difficulty reaching
    • Overhead
    • Behind back
  • Activities modified
  • Then stiffness slowly resolves

Examination

  • Muscle atrophy
  • No point tenderness
  • Markedly ↓ ROM, especially
    • Abduction
    • Rotation
    • Pain on forced movement
    • Most sensitive indicator is pain on forced external rotation
  • Scapulothoracic movement substituted for glenohumeral movement

Investigations

Plain Radiography

  • Rule out other conditions
  • Usually normal but may see relative osteopaenia

Bone Scanning

  • May show diffuse ↑ uptake in shoulder

Arthrography

  • Reduced volume < 10mls (normal shoulder 20-30ml)
  • Obliterated axillary capsular recess
  • Irregular joint outline
  • Variable filling of the bicipital tendon sheath
  • 6-20% have normal arthrogram

Arthroscopy

  • Technically demanding due to small capsule
  • Synovitis often present with obliteration of the inferior recess
  • Nevaiser suggested four stagesStage I – Mild reddened synovitisStage II – Acute synovitis with adhesion of dependent foldsStage III – Maturation of adhesionsStage IV – Chronic adhesions

Differential Diagnosis

  • GHJ Osteoarthritis
  • Rotator cuff tear
  • Missed Post-GHJ Dislocation
  • RSD
  • AVN

Treatment

Nonoperative

Primary consideration is prevention

  • Early ROM after trauma or surgery
  • Educate care-givers
  • Supportive care primary goal

Reassurance as first treatment

HCLA 2nd line

Avoid physiotherapy as makes it more painful & doesn’t ↑ ROM

Supportive

  • Careful explanation of
    • Nature of disease
    • Natural history
    • Reassurance

Freezing Phase

Directed towards pain relief

  • Simple Analgesics / NSAID
  • Sedatives
  • Sling
  • Ice
  • TENS

Physiotherapy & exercises of no benefit

  • Can make pain worse
  • Can be used to maintain strength of cuff & periscapular muscles?

Frozen Phase

  • Encourage hand use to avoid RSD
  • ? Consider Hydrostatic Distension at this stage if desperate

Thawing Phase

  • Gentle ROM & strengthening
  • ? MUA or Distension

Operative Treatment

MUA & steroid injection

  • Controversial
  • Technique (Nevaiser)
    • At least after 6/12 » late Frozen or early Thawing
    • GA
    • Shoulder MUA to regain ROM “out – up – in”
      • External rotation first
      • Then abduction
      • Then internal rotation in abduction
    • Then HCLA
    • Sensation of tearing is the axillary fold tearing on A/S
    • Shoulder abduction 90° for 2/52
    • Postoperative physiotherapy
  • Results
    • Uncertain if alters natural history
    • Reports vary from
      • Shorter rehabilitation time
      • Decreased period of stiffness
      • No ↓ in course of disease
      • No benefit with significant complications
  • Contra-Indications of MUA
    • Osteopaenia
    • Previous fracture or surgery
    • PVD
    • History instability
  • Complications of MUA
    • Humeral fractures & dislocations
    • Cuff tears
    • Increased inflammation & scarring
    • Radial nerve palsy

Hydrostatic Distension

  • Uncertain at what stage to use : ? Frozen or Thawing
  • Technique
    • Needle into GHJ under LA
    • Joint forcefully distended by injection
      • 5ml LA
      • 1ml Steroid
      • Up to 40ml Saline
    • Distension until capsule ruptures
      • Sudden drop in resistance
    • Immediate postoperative physiotherapy
  • Results
    • Immediate resolution of pain
    • Normal functional ROM by 4/52

Other

  • Arthroscopy*
  • Open Capsulotomy
    • Don’t release axillary pouch

*Capsule rent with MUA usually along anterior capsule & inferiorly through most of IGHL

Some surgeons now suggest controlled division of the capsule arthroscopically – ie MUA without the risk of fractures & dislocations

Problem is arthroscopic access in frozen shoulder

Prognosis

  • Traditionally thought to be benign & self-limiting
  • Resolves after 12-36/12
    • Average 18 months (Chris Blenkin says 2-5 years is average)
    • Maximum 10 years
  • Most have no significant symptoms or functional restriction
  • But not as benign as previously thought
    • 20% have mild pain
    • 30-60% have ↓ ROM
      • Usually external rotation (limitation of ER to less than 60% of opposite)
    • Treat aggressively to avoid Osteoarthritis