A Rare Etiology Of Shoulder Pain In A Collegiate Football Player

HISTORY: A 21-year-old collegiate football wide receiver sustained a right shoulder injury while being tackled during a game. During the tackle, he landed on the posterosuperior aspect of his right shoulder with his arm adducted across his body. He developed posterior shoulder pain and weakness with lifting his arm. He had no neck pain, radiation of pain down his arm, numbness or tingling. He had no prior history of brachial plexus or shoulder injuries. PHYSICAL EXAM: Initial exam in the athletic training room revealed tenderness of the posterior shoulder girdle, supraspinatus, and infraspinatus. Active range of motion was limited to 90 degrees of shoulder abduction and 90 degrees of shoulder forward flexion with associated pain. There was normal range of motion of external rotation and internal rotation. Strength testing revealed 3/5 shoulder abduction, forward flexion and external rotation. Neurovascular testing was intact. Repeat exam the following day revealed progressive loss of active range of motion to 30 degrees of shoulder abduction and 20 degrees of shoulder forward flexion. DIFFERENTIAL DIAGNOSIS: 1. Rotator cuff tear 2. Labral Tear 3. Brachial Plexus Injury 4. Peripheral Mononeuropathy 5. Cervical Radiculopathy TEST AND RESULTS: Right shoulder anteroposterior, scapular Y and axillary lateral radiographs: Os acromiale. No evidence of acute fracture or dislocation. MRI of right shoulder without contrast: Mild edema within the suprascapular and spinoglenoid notches. No evidence of discrete tears of the rotator cuff or labrum. EMG: No spontaneous activity on needle EMG and normal motor units on activation of the infraspinatus, supraspinatus and deltoid. Limited study given time since injury. FINAL/WORKING DIAGNOSIS: Suprascapular mononeuropathy secondary to direct trauma TREATMENT AND OUTCOMES: 1. Relative rest with non-steroidal anti-inflammatories 2. Range of motion and rotator cuff and scapular strengthening exercises 3. Methylprednisolone dose pack 4. Ultrasound-guided suprascapular notch corticosteroid injection. Patient reported immediate improvement of pain, but without complete resolution. 5. Fluoroscopy-guided spinoglenoid notch corticosteroid injection. 6. Returned to sport at 100% in 2 weeks post-injury with full and painless range of motion and strength.