Shoulder Rotator Cuff Examination
The rotator cuff examination tests each of the four muscles individually. Examiners expect you to know the specific tests for supraspinatus, infraspinatus, teres minor, and subscapularis. Lag signs indicate complete tears, while weakness with pain may indicate partial tears or tendinopathy.
Quick Reference One-Pager
Rotator Cuff Muscles
- Supraspinatus: Initiates abduction (0-30°)
- Infraspinatus: External rotation (main)
- Teres Minor: External rotation (assists)
- Subscapularis: Internal rotation
Key Tests
- Supraspinatus: Jobe's (Empty Can), Full Can
- Infraspinatus: External rotation lag, Hornblower's
- Subscapularis: Lift-off, Bear-hug, Belly-press
- Teres Minor: Hornblower's sign
Lag Signs (Complete Tears)
- External rotation lag sign (infraspinatus)
- Drop arm sign (supraspinatus)
- Internal rotation lag sign (subscapularis)
Additional Tests
- Drop arm test
- Rent test (palpable gap)
- Impingement signs (may coexist)
Rotator Cuff Anatomy
Key Anatomy
Rotator Cuff Muscles (SITS):
- Origin
- Supraspinous fossa
- Insertion
- Greater tuberosity (superior)
- Innervation
- Suprascapular (C5,6)
- Action
- Abduction initiation
- Origin
- Infraspinous fossa
- Insertion
- Greater tuberosity (middle)
- Innervation
- Suprascapular (C5,6)
- Action
- External rotation
- Origin
- Lateral scapula
- Insertion
- Greater tuberosity (inferior)
- Innervation
- Axillary (C5,6)
- Action
- External rotation
- Origin
- Subscapular fossa
- Insertion
- Lesser tuberosity
- Innervation
- Subscapular (C5,6)
- Action
- Internal rotation
Tear Patterns:
- Most tears begin in supraspinatus
- Progression: Supraspinatus → Infraspinatus → Subscapularis
- Massive tear: 2+ tendons or greater than 5cm
Supraspinatus Tests
Special test
Jobe's Test (Empty Can)
Supraspinatus integrity and strength
Technique
- 1Arms at 90° abduction in scapular plane (30° forward)
- 2Arms internally rotated (thumbs pointing DOWN - empty can position)
- 3Examiner applies downward pressure on both arms
- 4Patient resists
Positive Sign
Weakness and/or pain compared to opposite side
Indicates
Supraspinatus pathology (tear or tendinopathy)
Diagnostic Accuracy
Ability to detect true positives
Ability to exclude false positives
Special test
Full Can Test
Supraspinatus integrity (alternative to Jobe's)
Technique
- 1Arms at 90° abduction in scapular plane
- 2Arms externally rotated (thumbs pointing UP - full can position)
- 3Examiner applies downward pressure
Positive Sign
Weakness and/or pain
Indicates
Supraspinatus pathology (may be more comfortable than empty can)
Diagnostic Accuracy
Ability to detect true positives
Ability to exclude false positives
Special test
Drop Arm Test
Complete supraspinatus tear
Technique
- 1Examiner passively abducts arm to 90°
- 2Ask patient to slowly lower arm to side
Positive Sign
Arm drops suddenly (cannot control descent)
Indicates
Complete supraspinatus tear (unable to control eccentric contraction)
Diagnostic Accuracy
Ability to detect true positives
Ability to exclude false positives
Infraspinatus Tests
Special test
External Rotation Strength Test
Infraspinatus and teres minor strength
Technique
- 1Elbow at 90° flexion, tucked at side
- 2Patient externally rotates against resistance
Positive Sign
Weakness compared to opposite side
Indicates
Infraspinatus tear or pathology
Diagnostic Accuracy
Ability to detect true positives
Ability to exclude false positives
Special test
External Rotation Lag Sign
Complete infraspinatus tear
Technique
- 1Elbow at 90° flexion at side
- 2Examiner passively externally rotates arm to near maximum
- 3Patient asked to hold position
- 4Examiner releases arm
Positive Sign
Arm springs back into internal rotation (positive lag)
Indicates
Complete infraspinatus tear (cannot maintain external rotation)
Diagnostic Accuracy
Ability to detect true positives
Ability to exclude false positives
Special test
Hornblower's Sign
Teres minor function (and posterior cuff)
Technique
- 1Arm in 90° abduction, elbow flexed 90°
- 2Patient attempts to externally rotate (like blowing a horn)
- 3Compare strength and ability to maintain position
Positive Sign
Inability to externally rotate or maintain position
Indicates
Teres minor and/or infraspinatus tear
Diagnostic Accuracy
Ability to detect true positives
Ability to exclude false positives
Subscapularis Tests
Special test
Lift-Off Test (Gerber)
Subscapularis integrity
Technique
- 1Patient's hand placed behind back (dorsum on lumbar spine)
- 2Ask patient to lift hand away from back (internal rotation)
Positive Sign
Inability to lift hand away from back
Indicates
Subscapularis tear
Diagnostic Accuracy
Ability to detect true positives
Ability to exclude false positives
Special test
Internal Rotation Lag Sign
Complete subscapularis tear
Technique
- 1Examiner passively positions hand behind back, lifts away from back
- 2Patient asked to hold position
- 3Examiner releases arm
Positive Sign
Arm falls back to rest on back (positive lag)
Indicates
Complete subscapularis tear
Diagnostic Accuracy
Ability to detect true positives
Ability to exclude false positives
Special test
Bear-Hug Test
Upper subscapularis integrity
Technique
- 1Patient places palm on opposite shoulder (arm across chest)
- 2Elbow in front of body
- 3Examiner tries to lift patient's hand off shoulder (external rotation force)
- 4Patient resists
Positive Sign
Weakness (cannot resist external rotation force)
Indicates
Upper subscapularis tear
Diagnostic Accuracy
Ability to detect true positives
Ability to exclude false positives
Special test
Belly-Press Test (Napoleon)
Subscapularis function
Technique
- 1Patient presses palm firmly against belly
- 2Elbow should remain forward of body in same plane as trunk
- 3Observe if elbow moves backward
Positive Sign
Elbow falls back behind trunk plane (uses shoulder extension instead)
Indicates
Subscapularis weakness or tear
Diagnostic Accuracy
Ability to detect true positives
Ability to exclude false positives
Additional Tests
Special test
Rent Test
Palpable rotator cuff defect
Technique
- 1Arm at side, slightly extended and internally rotated
- 2Palpate anterior acromion
- 3Walk fingers anteriorly to palpate rotator cuff insertion on greater tuberosity
Positive Sign
Palpable gap or defect in the cuff (soft tissue void)
Indicates
Full-thickness rotator cuff tear
Diagnostic Accuracy
Ability to detect true positives
Ability to exclude false positives
Interpretation
Clinical Patterns
Pain with Weakness:
- Tendinopathy (intact cuff)
- Partial tear
- Pain inhibition of intact muscle
Weakness without Pain:
- Complete tear (lag sign positive)
- Neurological (suprascapular nerve)
Massive Rotator Cuff Tear Signs:
- Multiple positive tests
- Pseudoparalysis (cannot actively elevate arm)
- Positive drop arm
- Multiple lag signs
- Atrophy in supraspinatus and infraspinatus fossae
Lag Signs = Complete Tears:
- External rotation lag sign → Infraspinatus tear
- Drop arm test → Supraspinatus tear
- Internal rotation lag sign → Subscapularis tear
Lag signs have HIGH SPECIFICITY - if positive, the tear is almost certainly complete.
Summary Presentation
“58-year-old woman with 6-month history of shoulder pain and weakness lifting arm.”
Common Patterns Table
- tests
- Jobe's weak/painful, Drop arm +
- clinicalFeatures
- Most common pattern
- atrophy
- Supraspinatus fossa
- tests
- Above + ER lag sign +
- clinicalFeatures
- Posterosuperior tear
- atrophy
- Both fossae
- tests
- Multiple lag signs +
- clinicalFeatures
- Pseudoparalysis
- atrophy
- Generalized
- tests
- Lift-off -, IR lag +
- clinicalFeatures
- Less common, often traumatic
- atrophy
- Anterior (hard to see)
Examiner Tips
Do
- Test all four muscles systematically
- Use lag signs for complete tears
- Compare with opposite side
- Look for atrophy from behind
- Know the difference between pain and weakness
Don't
- Forget subscapularis (often missed)
- Miss the drop arm test
- Ignore Hornblower's sign for teres minor
- Rely on single test - use combinations
- Forget to examine for impingement (often coexists)