Frozen shoulder is an insidious, painful stiffening of the glenohumeral joint passing through various well defined phases of clinical spectrum, resulting in severely compromised functional ability of the joint but with complete resolution in due course of time albeit with a residual deformity.
Terms Used Various authors have used differing terms to describe it, viz., adherent bursitis, adhesive capsulitis, obliterative arthritis, periarthritis, pericapsulitis, etc
it occurs in 2-5% of the general population, with an incidence rate of 2.4 per 1000 years. Women are affected more frequently, in the fourth or sixth decade of life with a peak incidence in the age range of 50-55 years. The non-dominant arm is more likely to be involved.
What Causes Frozen Shoulder?
A number of theories have put forth by researchers; some are outlined below.
- Familial association
- Neuropathic Mechanisms: Suprascapular nerve compression
- Secondary Cause: esp. diabetes mellitus, pulmonary TB, thyroid disease, rheumatoid arthritis, post MI patients, cardiac surgery, Parkinson’s disease
- Immobilization: Frozen shoulder occurs with increased frequency in post MI or stroke patient
It is characterized by pain exhibiting following characteristics:Insidious onset,non localized pain over the deltoid region Pain on movementRestriction of movementsNocturnal painPain on lying on the affected shoulder (characteristic)Near total loss of active as well as passive external rotation of the shoulderSelf limiting; lasts for 2-3 years residual disability is present in a small percentage of patients.
- Clinical: frozen shoulder is a clinical diagnosis
- Laboratory tests: for HLA, C-reactive protein, ESR
- Radiology: no to rule out conditions like osteoarthritis
- Arthrography: ? in the joint capsule volume from 20-30 ml to 5-10 ml can be demonstrated
- MRI: thickening of the capsule and synovium of more than 4mm at the level of the axillary fold is highly suggestive of frozen shoulder, MRI high sensitivity index for thickness of joint capsule but not for volume of the joint space
- Contrast Technetium-99m diphosphonate bone scan: shows ? uptake on affected side
When definite diagnosis is difficult, arthrography is probably the investigation of choice.
Modalities of treatment
Aim of treatment is to reduce pain and increase the shoulder mobility. In general, treatment of any painful shoulder condition involves the reduction of muscle spasms which can be achieved by the RICE treatment.
Analgesics for pain reliefNSAIDS for anti-inflammatory actionAnti-depressants: like diazepam or amytryptiline to counter sleep disturbances
effective in the early phase of the diseaseside effects of oral steroids have to be taken into account; can cause rebound increase of symptomseffectiveness does not last beyond 6 weeks
Intra-articular steroid injections
used during early phase (early use restricts the synovitis thus decreasing the duration of the condition) not indicated during the adhesive phase i.e. usually after 3-4 weeks also, used during manipulation under anaesthesia.15-60 mg of triamcinolone acetate/ 20mg methyl prednisolone acetate with 0.5-1ml of 1% lignocaineInjection site : 1 cm distal and 1 am lateral to the coracoid process on full extension of the humerus with the elbow in a relaxed positionSome advocate simultaneous intra-articular and bursa injections for pain relief
Suprascapular nerve blocks for pain relief stellate ganglion block
in refractory cases, i.e. cases not responding to conventional therapy for more than 3-6 monthsmanipulation under anaesthesia (MUA), most reliable to improve movement arthroscopic release of capsule
initiated in the first phase of the disease to restore movement or after surgery to maintain the range of movement achieved by surgery exercise indicated under observation of a physical therapist or prescription of a home program.gentle stretching and range movement exercises are recommended avoiding ‘too much, too early’ : 1 hour sessions, 3 days per week, for 4 week totaling 12 sessionsMaitland mobilization techniques, active & passive as well as auto-assisted range of motion exercises and aid of physical agents like dyna bandsCodman exercises ‘wall climbing’ or ‘reaching’ found to be effective results better with moderate exercise within normal limits of painvigorous and forceful exercise contraindicated
Clear evidence of efficacy of different modalities of treatments is lacking. Hence, the management of frozen shoulder has been a subject of considerable debate, especially the rationale of intra-articular injections and/ or physiotherapy and the effectiveness of one over the other if indicated separately.
A lot of the studies have found corticosteroid injections to be slightly more effective, especially in the early stage of the disease, in alleviating pain. This advantage, however, is lost at the end of three to four weeks. Coritcosteroids, thereafter, do not alter the course of disease. The evidence in favour of physiotherapy as an effective mode of treatment is too flimsy as well.
Lack of correlation between subjective and objective findings on the restriction of movements in frozen shoulder is well documented in literature.
It needs to be investigated whether this supposed improvement in the range of movement perceived by the patient is responsible for the ‘spontaneous resolution definition’ of the condition. For a normal individual, active elevation of 150°, external rotation of 50° and internal rotation up to the 8th thoracic vertebra is sufficient for day to day activities. These functional needs further reduce during the 5th and 6th decade of life; therefore the perceived resolution of frozen shoulder.The resolution of the condition may therefore represent excellent adaptation of the individual to the decreased range of movements
Points of Further interest
- research into etiology of the condition
- research into designing of effective physiotherapy techniques
- newer drugs with potential for control of effective symptoms
- investigation into the ‘spontaneous resolution theory’