Clinical Features of Rotatory Cuff Injury
Rotator cuff tears present with a characteristic triad of shoulder pain (especially at night and radiating down the upper arm), weakness in specific movements (particularly abduction and external rotation), and limited range of motion.
Primary Clinical Presentation
The clinical features depend on whether the tear is acute traumatic or degenerative:
Pain Characteristics
- Night pain is particularly typical of full-thickness tears 1, 2
- Pain radiates down the upper arm 3
- Pain worsens with overhead activities and repetitive movements 1
- In acute traumatic tears, pain occurs immediately following injury (fall, shoulder dislocation, or contact sports) 1, 2
Weakness and Functional Limitation
- Supraspinatus weakness (difficulty initiating arm abduction) 4
- Weakness in external rotation (infraspinatus/teres minor involvement) 4, 3
- Limited active elevation with preserved passive range of motion 2
- Positive "shrug sign" in acute macrotrauma cases (patient shrugs shoulder to compensate for inability to actively elevate arm) 2
Physical Examination Findings
The most predictive clinical triad consists of: 4
- Supraspinatus weakness
- Weakness in external rotation
- Positive impingement signs
When all three are positive, or when two are positive in patients ≥60 years old, there is a 98% probability of rotator cuff tear 4. The combined absence of these features effectively excludes the diagnosis.
Additional Examination Findings
- Deltoid and rotator cuff muscle atrophy (in chronic tears) 3
- Tenderness over the rotator cuff insertion 3
- Limited passive range of motion 3
- Positive relocation test (suggests subtle anterior instability in young overhead athletes) 2
Age-Related Presentation Patterns
Younger Patients (<40 years)
- Tears typically result from acute trauma (falls, shoulder dislocations, contact sports) 1
- In overhead athletes: pain with decreased throwing velocity, often with subtle anterior instability 2
- May have superior-posterior labral injury (internal impingement pattern) 2
Older Patients (>40 years)
- Degenerative tears from chronic tendon wear 1
- Often have chronic shoulder pain associated with overhead activities 2
- 54% of asymptomatic patients ≥60 years have rotator cuff tears 1
- Middle-aged patients with primary impingement syndrome 2
Important Clinical Caveats
Many rotator cuff tears are asymptomatic: 16.9% of people without shoulder symptoms have rotator cuff tears on imaging 5. This increases dramatically with age—31% prevalence in the seventh decade of life 1.
Dominant arm involvement: Tears are more common in the dominant arm, particularly in those with repetitive overhead work or heavy labor 1, 5.
Risk factors to elicit in history 5:
- History of trauma (strongest risk factor)
- Dominant arm affected
- Age >40 years
- Repetitive overhead activities (painters, carpenters, baseball pitchers, tennis players)
Clinical Examination Protocol
A structured 15-minute examination should include 6:
- Range of motion testing with goniometer
- Strength testing with dynamometer (abduction and external rotation strength)
- Specific impingement tests
- Assessment for supraspinatus and external rotation weakness
Clinical examination alone is 100% sensitive but only 73.8% specific for rotator cuff tears 7, meaning it effectively rules out tears when negative but requires imaging confirmation when positive due to overlap with other shoulder pathologies.