Clinical Testing for Periarthritis
What is Periarthritis?
The term "periarthritis" is outdated and clinically inadequate—it encompasses multiple distinct shoulder pathologies that require specific diagnosis through targeted clinical tests and imaging. 1
The syndrome historically called "periarthritis humeroscapularis" (frozen shoulder/adhesive capsulitis) must be differentiated from other periarticular inflammatory conditions including rotator cuff tendonitis, biceps tendinitis, calcific tendonitis, and bursitis. 2, 1
Clinical Examination Tests
Essential Physical Examination Maneuvers
For suspected shoulder periarthritis, perform specific functional tests to differentiate pathologic features:
Range of motion assessment: Document both active and passive glenohumeral movement in all planes (forward flexion, abduction, internal/external rotation). True adhesive capsulitis shows restricted passive motion, while rotator cuff pathology shows preserved passive range. 3, 1
Rotator cuff testing: Assess each rotator cuff tendon individually with resisted movements. Empty can test (supraspinatus), external rotation against resistance (infraspinatus/teres minor), and lift-off test (subscapularis) identify specific tendon involvement. 2, 1
Impingement signs: Neer's sign (pain with forced forward flexion) and Hawkins-Kennedy test (pain with internal rotation at 90° flexion) suggest subacromial impingement or rotator cuff tendonitis. 1
Biceps tendon evaluation: Speed's test (resisted forward flexion with supinated forearm) and Yergason's test (resisted supination with elbow flexed) detect biceps tendinitis. 2, 1
Critical Examination Pitfall
Physical examination alone detects only 8.3-15% of periarticular pathology compared to imaging, making it inadequate as the sole diagnostic modality. 2 Tenderness on palpation was present in only 15% of cases where imaging confirmed periarthritis. 2
Laboratory Testing
Inflammatory Markers
ESR and CRP: Should be performed at baseline when inflammatory periarthritis is suspected. Normal or mildly elevated markers suggest non-inflammatory causes (adhesive capsulitis, degenerative disease), while significantly elevated markers indicate inflammatory arthritis or infection. 4, 5, 6
Autoantibodies: RF and ACPA testing should be performed if rheumatoid arthritis is suspected (multiple joint involvement, morning stiffness >30 minutes, symmetric distribution). Negative tests do not exclude RA progression. 4, 6, 7
When to Suspect Systemic Disease
If periarthritis occurs at multiple sites (wrist, elbow, hip, knee, ankle), consider generalized hydroxyapatite deposition disease or underlying rheumatoid arthritis. 8, 2 In these cases, obtain complete autoimmune panel including ANA, RF, anti-CCP, and inflammatory markers. 6
Imaging Studies
First-Line Imaging
Plain radiographs should be obtained in all patients with suspected periarthritis to identify calcific deposits, exclude fractures, and assess for erosive changes. 4, 5, 7
Calcific periarthritis: Radiographs show characteristic periarticular calcifications (calcium hydroxyapatite deposits) adjacent to joints, most commonly in the shoulder. 8, 9
Acute calcific periarthritis (ACP): Presents with acute monoarticular pain and juxtaarticular calcifications that may be mistaken for gout or infection. One-third have antecedent trauma history. 9
Advanced Imaging
Ultrasonography detects 14.2% of effusions and 21.7% of periarthritis compared to 8.3% and 15% by physical examination alone—making it superior for diagnosis. 2
High-resolution ultrasound with power Doppler: Increases detection to 34% and identifies specific pathology (rotator cuff tears, tendonitis, bursitis, effusions). 2
MRI indications: Reserved for persistent symptoms unresponsive to treatment, diagnostic uncertainty, or when surgical planning is needed. MRI is not routinely recommended for initial diagnosis. 4, 6
Imaging Pitfall
Periarticular calcifications in acute calcific periarthritis may be mistaken for gout, pseudogout, or infection—correlate with clinical presentation (acute onset, monoarticular, self-limited course). 9 Calcifications typically resolve or markedly decrease within 2-3 weeks radiographically. 9
Diagnostic Arthrocentesis
Perform arthrocentesis urgently if septic arthritis cannot be excluded clinically (warm, swollen joint with fever, acute onset). 4, 6, 7
Synovial fluid analysis: Send for cell count with differential, Gram stain, aerobic/anaerobic culture, and crystal analysis. 4
Withhold antimicrobials: If patient is medically stable, withhold antibiotics for at least 2 weeks prior to aspiration to increase organism recovery. 4
Management Approach
Conservative Treatment
For adhesive capsulitis/frozen shoulder, intra-articular corticosteroid injection provides rapid short-term pain relief (4 weeks), while platelet-rich plasma (PRP) injection shows superior long-term outcomes at 24 weeks. 3
Triamcinolone 40 mg intra-articular: Better VAS and DASH scores at 4 weeks compared to PRP. 3
PRP 2 mL intra-articular: Significantly better pain (VAS 14.33 vs 31.63) and disability (DASH 18.08 vs 31.76) scores at 24 weeks compared to corticosteroid. 3
Acute calcific periarthritis: Treatment is conservative with NSAIDs. Symptoms typically reduce within 4-7 days; calcifications resolve within 2-3 weeks. 9
When Conservative Treatment Fails
Refer to rheumatology if joint swelling persists, symptoms fail to improve despite initial management, or diagnostic uncertainty exists with complex presentations. 6 Consider manipulation under anesthesia or surgical management for refractory adhesive capsulitis. 3
Critical Diagnostic Algorithm
Obtain detailed history: Duration of symptoms, trauma history, morning stiffness duration, number of joints involved, systemic symptoms. 4, 6, 9
Perform targeted physical examination: Specific functional tests for rotator cuff, impingement, biceps tendon pathology. Document active and passive range of motion. 2, 1
Order plain radiographs: Identify calcifications, erosions, fractures. 4, 7, 9
Check inflammatory markers: ESR/CRP to distinguish inflammatory from non-inflammatory causes. 4, 5, 6
Perform ultrasound: If physical examination is negative but clinical suspicion remains high, or to characterize specific soft tissue pathology. 2
Aspirate if infection suspected: Send for cell count, Gram stain, culture, crystals. Do not delay if septic arthritis is possible. 4, 6, 7
Autoantibody testing: Only if multiple joints involved, morning stiffness >30 minutes, or symmetric distribution suggesting inflammatory arthritis. 4, 6, 7