Frozen shoulder frozen shoulder

Evolutionary phases

Adhesive capsulitis classically evolves in three distinct phases, the duration and intensity of which vary from one patient to another:

Risk factors and associated conditions

• Type 1 and Type 2 Diabetes: Most strongly associated risk factor — prevalence of 10–20% % in the diabetic population vs 2–5% % in the general population; risk proportional to duration of diabetes and glycemic control level (HbA1c); diabetic forms often bilateral, more severe, and less responsive to conventional treatments; mechanism involves advanced glycation of joint capsule proteins (AGEs)
• Hypothyroïdie : association bien documentée — prévalence de la capsulite estimée à 10 % chez les patients hypothyroïdiens ; le dépistage thyroïdien (TSH) est recommandé devant toute capsulite sans facteur déclenchant évident
• Prolonged shoulder immobilization: post-fracture of the humerus or clavicle, post-shoulder or breast surgery (axillary dissection), immobilization for pain — kinesophobia and avoidance of movement contribute to the development of capsular retraction
• Pathologies of the ipsilateral shoulder: rotator cuff tendinopathy or tear, subacromial bursitis, glenohumeral osteoarthritis — can precipitate secondary adhesive capsulitis through reflex immobilization.
• Cardiovascular disease, dyslipidemia, metabolic syndrome: epidemiological associations observed in several studies, possibly mediated by common systemic inflammatory mechanisms
• Dupuytren's disease and palmar fibromatosis: sharing the same fibroblast proliferation mechanisms; the coexistence of the two conditions is frequent and indicates an individual susceptibility to fibrosis
• Female sex and age 40–60 years: peak incidence in perimenopause; possible role of hormonal fluctuations in susceptibility to joint fibrosis
• History of contralateral capsulitis: 5 to 34 % risk of developing contralateral shoulder capsulitis in the following years

Symptoms

The clinical presentation of adhesive capsulitis is relatively characteristic, although the presentation may vary depending on the stage of the condition:

• Diffuse shoulder pain with insidious onset: deep, poorly localized pain, radiating to the deltoid and sometimes to the arm; typically aggravated at night (frequent nocturnal awakenings, difficulty sleeping on the affected side) and by movements at the end of range of motion; predominates in phase 1.
• Progressive limitation of mobility in all directions: cardinal sign of capsulitis; the limitation characteristically affects passive external rotation (earliest and most constant sign), abduction, anterior elevation, and internal rotation behind the back; the limitation is both active and passive, which distinguishes it from a rotator cuff tear (active limitation but preserved passive mobility)
• Major functional impact on daily life activities: difficulty dressing (putting on a jacket, fastening a bra), doing hair, performing personal hygiene, driving, reaching for objects overhead or behind the back.
• Absence of a triggering trauma in idiopathic forms: primary capsulitis begins without an identifiable cause, which distinguishes it from secondary capsulitis (post-traumatic, post-surgical).
• Spontaneously resolving but prolonged evolution: the majority of patients recover in 1 to 3 years, but 20 to 50 % retain residual limitation, especially in external rotation; this spontaneous resolution does not exempt from treatment to accelerate recovery and reduce pain

Diagnosis

The diagnosis of adhesive capsulitis is primarily clinical. Further investigations mainly serve to rule out differential diagnoses and to confirm capsular retraction in atypical cases:

• Clinical examination: painful limitation of passive and active mobility in all directions, predominantly external rotation; passive external rotation test (elbow at 0° abduction) - characteristic limitation; absence of subacromial impingement signs (no purely positive Neer or Hawkins signs); no significant muscle strength deficit (unlike massive rotator cuff tears)
• Standard shoulder X-ray (neutral rotation AP, Lamy lateral view): normal in idiopathic capsulitis or showing at most localized osteoporosis of the humeral head; essential for ruling out glenohumeral osteoarthritis, calcification (calcific tendinitis), fracture, or bone tumor.
• Shoulder ultrasound: thickening of the inferior joint capsule and coracohumeral ligament (thickness > 4 mm); possible joint effusion in inflammatory phase; rules out a full-thickness rotator cuff tear, isolated subacromial bursitis; operator-dependent examination but accessible and non-irradiating.
• Shoulder MRI (with gadolinium injection if available): reveals capsular fibrosis and thickening, synovial contrast enhancement in the inflammatory phase, disappearance of the axillary recess and subcoracoid recess - specific signs of capsulitis; indicated in cases of diagnostic doubt or to rule out associated pathology (rotator cuff tear, humeral head lesion, tumor).
• Arthrograhy or MR arthrography: demonstration of a reduction in joint volume (< 10–15 mL as opposed to 25–30 mL normally) and disappearance of the recesses — historical gold standard examination, now largely replaced by MRI in routine practice
• Oriented biological workup: fasting blood glucose and HbA1c (screening for unknown diabetes), TSH (hypothyroidism), inflammatory markers (CRP, ESR) — to look for a secondary etiology or a contributing comorbidity

Differential diagnoses

• Rotator cuff tendinopathy or tear: limited active range of motion but preserved passive range of motion (unlike adhesive capsulitis); weakness in abduction or external rotation; ultrasound or MRI confirms tear
• Calcific tendinopathy of the shoulder: severe acute pain, sometimes disabling; calcification visible on standard X-ray; mobility often only slightly limited outside of acute episodes
• Glenohumeral osteoarthritis: progressive but visible limitation on X-ray (joint space narrowing, osteophytes, subchondral sclerosis); primarily affects older patients or after trauma.
• Septic or microcrystalline arthritis (chondrocalcinosis): sudden onset, marked local inflammatory signs, possible fever for septic arthritis; diagnostic and therapeutic emergency; joint aspiration essential
• Bone tumor of the proximal humerus or metastasis: intense nocturnal pain, weight loss, general deterioration; X-ray and MRI allow for diagnostic orientation.

Treatment

• Physiotherapy and kinesiotherapy: cornerstone of treatment at all phases; gentle and progressive capsular stretching (passive mobilization, self-stretching), strengthening of periarticular muscles during the recovery phase; in the painful acute phase, aggressive physiotherapy is counterproductive and worsens inflammation - stretching should be performed without significant pain; recommended duration: 3 to 6 months minimum
• Oral nonsteroidal anti-inflammatory drugs (NSAIDs): useful in phase 1 for pain management; limited effectiveness on the progression of stiffness; to be prescribed at the minimum effective dose and for the shortest possible duration due to gastrointestinal and cardiovascular side effects
• Intra-articular corticosteroid injection: most effective short-term treatment (4 to 12 weeks) for pain reduction and functional improvement, particularly in phase 1 and early phase 2; ultrasound guidance recommended for accuracy and safety; 1 to 3 injections spaced 4 to 8 weeks apart; long-term benefit comparable to physical therapy alone but accelerated recovery time; caution in diabetic patients (transient post-injection hyperglycemia)
• Hydrodilatation (joint distension): intra-articular injection of a large volume of saline (20–40 mL) ± corticosteroid under ultrasound or fluoroscopic guidance, causing mechanical distension of the contracted capsule; effective in accelerating recovery of mobility in phase 2; can be combined with physiotherapy immediately after the procedure
• Manipulation Under Anesthesia (MUA): Forced mobilization of the shoulder under general anesthesia or interscalene block to break down capsular adhesions; reserved for refractory capsulitis after 6 months of well-conducted conservative treatment; risk of humeral fracture, rotator cuff tear, or brachial plexus injury — requires careful patient selection
• Arthroscopic capsulotomy: surgical division of retracted capsular structures (coracohumeral ligament, anterior and inferior capsule) under arthroscopy; reference treatment for refractory forms after failure of conservative treatment ≥ 6 months; short hospitalization, recovery guided by intensive postoperative physiotherapy; success rate > 90 % in published series
• Comorbidity management: optimizing glycemic control in diabetic patients (HbA1c reduction) - a proven prognostic factor for recovery speed; hypothyroidism treatment; smoking cessation

Consult at Clinique Omicron

Clinique Omicron physicians assess shoulder pain and stiffness, order appropriate imaging, and refer to physiotherapists and specialists in musculoskeletal medicine or orthopedics based on severity and stage of progression. Early management—starting with the first signs of limited external rotation—is key to optimal functional recovery. Consultations are available at our Quebec branches as well as via telemedicine throughout the province. To book an appointment, visit cliniqueomicron.ca.

The content of this page is provided for informational purposes only and does not substitute for the advice of a qualified healthcare professional. The differential diagnosis of shoulder pain requires a comprehensive clinical examination and appropriate investigations by a physician or a musculoskeletal medicine specialist.