Introduction
Shoulder injury where one or more of the tendons or muscles of the rotator cuff of the shoulder get torn.
- M/C tendon injury in adults
Anatomy
Rotator cuff (RC) muscles:
Rotator cuff tendons form confluence with the joint capsule and coracohumeral ligament, and insert on the humeral tuberosity.
- Subscapularis (SC) (largest and strongest RC muscle)
- Supraspinatus (SS)
- Infraspinatus (IS)
- Teres minor (TM)
Classification
- Partial-thickness tears (PTT): Can be bursal-sided or articular-sided tears
- Full-thickness tears (FTT): Over the course of time, PTT enlarge and propagate into FTT
Aetiology
Risk factors:
- Age (M/C risk factor)
- Smoking
- Family history
- Poor posture
- Other risk factors: Trauma, hypercholesterolemia, and occupations or activities requiring significant overhead activity
Causative factors:
- Younger patients: Overuse tendinopathy
- Older patients: Osteoarthritis
Pathophysiology
The rotator cuff is weakened by both extrinsic and intrinsic factors, leading to gradual failure of tendon with or without superimposed acute injury, which finally results in full-thickness tear.

Clinical features
Depending on when the patient presents, the tendon will be anywhere from tendinopathy to partial tear to complete tear.
Shoulder pain:
Pain can be acute and arise from a traumatic event, or it can be gradual and mild, but steadily increasing. Active individuals present when they can no longer do their sport, activity, or job without causing pain. Often they will try to adapt or alter their biomechanics to remain active. Only when they can no longer adapt will they present.
- Increasing pain and difficulty with:
- Overhead activity, activities of daily living
- Lifting/carrying heavy objects
- When lying on their side to sleep
- Radiation down into the area of deltoid muscle (occasionally)

Diagnosis
Clinical examination:
Plain radiograph:
- Grashey view: Activates deltoid muscle allowing proximal humeral migration in chronic, larger tears
- Scapular Y view: Assess acromial spurs associated with cuff tears that may need to be addressed at the time of surgery
- Axillary view: Demonstrate joint space narrowing as well as potential anterior or posterior humeral subluxation

MRI:
The presence or absence of muscle atrophy should be documented in full-thickness tears and graded according to the Goutallier classification. Concomitant pathology to other structures such as the long head of the biceps, labrum and early glenoid and humeral chondrosis should be assessed.

Management
Conservative management:
Physical therapy along with activity modifications, anti-inflammatory and analgesic medications form the pillars of nonoperative treatment.
- NSAIDs (first-line medication)
- Subacromial corticosteroid injections (short-term pain relief and to facilitate rehabilitation)
- Physical therapy and home exercise programs
Surgical management:
