II. Epidemiology
- Rarely occurs under age 40 years
- Exception: Athletes or with significant injury such as Shoulder Dislocation or MVA
III. Pathophysiology
- Typically results from continued deterioration or degeneration
- Rotator Cuff Tear typically occurs with minor Trauma in Older Patients
- Partial or complete rupture
- Full thickness tears account for 5-40% of Rotator Cuff Tears
- Rotator Cuff Rupture associated with Shoulder Dislocation
- Occurs in 50% of dislocations over age 50 years
IV. Mechanism
- Fall on Outstretched Hand
- Lifting heavy object
- Shoulder Dislocation
- Motor Vehicle Accident (or other high mechanism injury)
V. Symptoms
VI. Signs
- Partial rupture appears similar as chronic Tendonitis
- Shoulder Range of Motion may be completely intact
-
Shoulder Weakness
- Abduction weakness more common (Supraspinatus tear)
- Active abduction
- Painful arc over 50 degrees
- Passive abduction
- Results in painful catch at 50 to 100 degrees
- Forward flexion weakness indicates subscapularis tear
- Tenderness over Rotator Cuff Tear site
- Defect palpated through deltoid in complete cuff tear
- Atrophy of cuff Muscles
-
Drop Arm Test positive
- Test Specificity: 98%
- Test Sensitivity: 10%
- Consider Local Lidocaine injection diagnostically
- Persistent difficult abduction suggests cuff tear
- Acute hemarthrosis and prominent Ecchymosis down arm
- Indicative of long standing cuff tear and Arthropathy
- Chronic Sub-deltoid swelling indicates large cuff tear
- Synovial Fluid escaped from glenohumeral joint
VII. Diagnosis
VIII. Imaging
-
Shoulder XRay
- Calcifications at Humerus tuberosity
- Degenerative Arthritis
- Acromioclavicular joints
- Glenohumeral joints
- Subacromial space narrowed on Shoulder PA View (high riding humeral head)
- Intact rotator cuff depresses the humeral head
- Complete Rotator Cuff Tear allows the humeral head to rise toward the acromion
- Cortical irregularity at supraspinatus insertion at greater tuberosity
- Present in 75% of Rotator Cuff Tears (esp. age >40 years old)
- No cortical irregularity at supraspinatus suggests no tear (misses 4% of tears)
- Jacobson (2004) Radiology 230:234-42 [PubMed]
-
Shoulder MRI
- Replaces arthrography
- Identifies smaller partial thickness tears as well as other pathology (e.g. labral tears)
- Best for younger patients (under age 40 years old)
-
Shoulder Ultrasound
- Safe and noninvasive
- Accurate in full thickness, large and moderate tears (esp. in patients over age 40 old)
-
Shoulder Arthrography (MRI is preferred)
- Differentiates full from incomplete Rotator Cuff Tear
- Invasive test
- Perform only if considering surgery
IX. Differential Diagnosis
X. Management: Referral Indications for Orthopedic Surgery (earlier is better)
- Young active patient with full thickness tear (best outcome with earlier intervention)
- Competitive athletes
- Severe functional deficit
XI. Management: Algorithm
- Initial Evaluation: Painful cuff range of motion
- Start with RICE-M for first 3 days
- Switch to moist heat after 2-3 days
- Apply for 1 hour
- Apply 2-3 times per day
- Relative Rest
- Avoid complete rest especially in older patients
- Risk of Frozen Shoulder
- Gentle Shoulder Range of Motion Exercises
- Prevents Frozen Shoulder
- NSAIDs
- Avoid overhead Shoulder activities or overuse
- Consider Shoulder XRay if Fracture suspected
- Re-evaluation in 2 weeks: Lack of improvement
- Early orthopedic referral if criteria above met
- Change NSAIDs
- Continue Shoulder Range of Motion Exercises
- Start Shoulder Strengthening Exercises
- Re-evaluation in 2 weeks: Lack of improvement
- Sub-acromial space Corticosteroid Injection
- Risk of weakening tendons
- Physical Therapy with Phonophoresis
- Sub-acromial space Corticosteroid Injection
- Re-evaluation in 2 weeks: Lack of improvement
- Shoulder MRI
- Orthopedics Consultation
XII. Complications
- Partial Thickness Rotator Cuff Tears
- Chronic Shoulder Impingement
- Calcific Tendonitis
- Rotator Cuff Tear progression
- Rotator cuff atrophy
- Full thickness tear progression (esp. older patients)
- Full Thickness Rotator Cuff Tears
- Suprascapular Neuropathy
XIII. References
- Greene in Wirth (2001) Musculoskeletal Care, p.141-3
- Krishman in DeLee (2003) Sports Medicine, p. 1065-92
- Monica (2016) Am Fam Physician 94(2): 119-27 [PubMed]