What are the stages of periarthritis (adhesive capsulitis) in an adult patient?

Stages of Adhesive Capsulitis (Frozen Shoulder)

Adhesive capsulitis progresses through three distinct clinical stages: the freezing (painful) stage, the frozen (adhesive) stage, and the thawing (resolution) stage, with each phase having characteristic pain patterns and range of motion limitations that guide stage-specific treatment approaches. 1, 2

Stage 1: Freezing (Painful) Phase

Clinical Characteristics:

• Progressive onset of severe shoulder pain that is often worse at night and interferes with sleep 3
• Gradual loss of both active and passive range of motion in all planes, with external rotation being the earliest and most significantly affected movement 4
• Pain precedes stiffness and is the dominant symptom 1, 2
• Duration: typically lasts 2-9 months 2
• Equal restriction of active and passive motion distinguishes this from rotator cuff pathology where active motion is more limited than passive 4

Key Diagnostic Features:

• External (lateral) rotation loss correlates most strongly with onset of shoulder pain 4
• Bone scintigraphy shows increased periarticular activity if performed 4, 3
• MRI reveals early capsular thickening, particularly in the rotator interval and axillary recess 4

Stage 2: Frozen (Adhesive) Phase

Clinical Characteristics:

• Pain begins to plateau or decrease while stiffness becomes the predominant feature 1, 2
• Severe restriction of abduction and all planes of motion, with external rotation remaining most limited 4
• Capsular contracture is established with thickening of the rotator interval and axillary recess 4
• Duration: typically 4-12 months 2
• Patients may develop compensatory scapulothoracic motion patterns 5

Functional Impact:

• Activities of daily living become significantly impaired 6
• Depression and sleep disturbances are common due to persistent disability 7, 3
• Can delay rehabilitation in patients with concurrent conditions like stroke 8, 7

Stage 3: Thawing (Resolution) Phase

Clinical Characteristics:

• Gradual spontaneous improvement in range of motion 1, 2
• Pain continues to diminish 2
• Duration: 12-42 months, though some patients never fully recover baseline motion 5, 2
• Recovery occurs in reverse order of loss, with external rotation typically the last to improve 4

Important Caveats:

• The condition is generally self-limiting with total disease duration of 2-3 years 2
• However, up to 40% of patients may have persistent pain and limited range of motion beyond this timeframe 2
• Early intervention in Stage 1 appears to provide better long-term outcomes than waiting until Stage 2 9

Stage-Specific Treatment Implications

Stage 1 (Freezing):

• Focus on pain control with NSAIDs, oral or intra-articular corticosteroids 1, 6
• Gentle range of motion exercises to prevent progression 1
• Early hydrodistension combined with physical therapy shows superior outcomes when initiated in Stage 1 versus Stage 2 9

Stage 2 (Frozen):

• Aggressive physical therapy becomes more important 1
• Consider manipulation under anesthesia, arthroscopic capsular release, or distension arthrography for refractory cases 5
• PRP injections show better long-term outcomes than corticosteroids at 24 weeks in this stage 6

Stage 3 (Thawing):

• Continue stretching and strengthening exercises 1
• Focus shifts to restoring full function and preventing recurrence 5

Critical Clinical Pearl: External rotation is the most sensitive early indicator and the last motion to recover, making it the key examination finding for both diagnosis and monitoring progression through stages 4.