What is the recommended physical assessment and treatment approach for a patient with a partial right rotator cuff (RC) tear, considering their medical history and potential comorbidities such as diabetes or rheumatoid arthritis?

Physical Assessment for Partial Right Rotator Cuff Tear

Begin with range of motion testing using a goniometer, strength testing with a dynamometer, and specific provocative tests that isolate the involved tendon—this structured approach can typically be completed in 15 minutes and is sufficient for diagnosis without immediate imaging in most cases. 1

Essential History Components

• Pain characteristics: Document pain location (anterior, lateral, or posterior shoulder), timing (at rest, at night, or with activity), and severity using a 0-10 visual analog scale 2, 1
• Mechanism of injury: Determine if traumatic onset (which trends toward full-thickness tears) versus insidious onset (more common with partial tears) 3, 4
• Functional limitations: Assess specific activities that provoke symptoms, particularly overhead activities and reaching behind the back 1
• Comorbidities: Document diabetes and rheumatoid arthritis status, as these affect healing capacity and treatment decisions 5

Structured Physical Examination Protocol

Range of Motion Assessment

• Active and passive forward flexion: Measure with goniometer in degrees 1
• Active and passive abduction: Measure in the scapular plane 1
• External rotation: Test at 0° and 90° of abduction 1
• Internal rotation: Document vertebral level reached with thumb behind back 1

Strength Testing (Critical Differentiator)

• Supraspinatus strength (empty can test): Greater abduction strength (Constant Power Score) is specifically associated with partial-thickness tears rather than full-thickness tears 4
• External rotation strength: Test at side and at 90° abduction—weakness is highly predictive of rotator cuff pathology 6, 1
• Internal rotation strength: Test lift-off and belly-press maneuvers 1

Provocative Tests (High Predictive Value)

Three positive findings are highly predictive of rotator cuff tear: 6

• Supraspinatus weakness (empty can test positive)
• Weakness of external rotation
• Positive impingement signs (Neer or Hawkins-Kennedy test)

For patients over 60 years, only two positive tests are needed for high predictive value 6

Additional Special Tests

• Painful arc: Pain between 60-120° of abduction suggests subacromial pathology 1
• Drop arm test: Inability to slowly lower arm from full abduction 1
• External rotation lag sign: Indicates infraspinatus/teres minor involvement 1

Documentation Requirements

Document the following specific findings: 1

• Numeric range of motion measurements in degrees for all planes
• Strength grades (0-5 scale) or dynamometer measurements for each rotator cuff muscle
• Positive/negative results for each special test performed
• Pain scores (0-10) at rest, with activity, and at night
• Functional limitations quantified (e.g., cannot reach overhead, cannot reach behind back to specific vertebral level)

Imaging Considerations

MRI without contrast or ultrasound should be obtained to confirm diagnosis and assess prognostic factors 7, 3

The imaging is essential to evaluate:

• Tear size and location (bursal versus articular surface) 3
• Degree of tendon retraction 3
• Muscle atrophy severity 5, 3
• Fatty infiltration grade (critical prognostic factor) 5, 3

Critical Pitfalls to Avoid

• Do not rely solely on clinical examination to differentiate partial from full-thickness tears: Most clinical findings do not distinguish between partial and full-thickness tears, with the exception of preserved abduction strength favoring partial tears 4
• Do not assume pain severity correlates with tear size: Asymptomatic rotator cuff tears are common, especially in older populations 3
• Do not perform multiple corticosteroid injections during the diagnostic phase: This may compromise tendon integrity and affect subsequent repair if needed 5
• Assess for pseudoparalysis: Inability to actively elevate the arm despite passive range of motion suggests massive tear, not partial tear 5

Initial Management Based on Assessment

For symptomatic partial-thickness tears, initiate conservative management with exercise therapy and/or NSAIDs 7

• Physical therapy demonstrates favorable outcomes with decreased pain and improved strength, particularly with eccentric rehabilitation protocols 2
• A single corticosteroid injection with local anesthetic may provide short-term improvement in pain and function 7
• NSAIDs or COX-2 inhibitors used concurrently with acetaminophen provide more effective pain control 3

Reserve surgical consultation for: 5, 3

• Persistent significant pain despite 3-6 months of conservative management
• Progressive functional decline
• Acute traumatic tears in younger, active patients
• Evidence of tear progression on repeat imaging