HISTORY: 15-year-old female national-level volleyball player with no PMH who presented for nagging right shoulder pain and subjective right arm weakness for 1.5 years. The patient did not endorse a specific inciting injury. The pain was located at the anterolateral aspect of the deltoid with radiation down the arm without numbness or tingling, made worse with volleyball activity and made better with rest. Due to her continued pain and right shoulder weakness, she was held from participating in volleyball matches. MRI arthrogram was negative for pathology, so she was referred for EMG.
PHYSICAL EXAMINATION: General Appearance: Young Caucasian female in no acute distress
Musculoskeletal: 4 out of 5 strength at right shoulder external rotation. 5 strength in bilateral upper extremities otherwise. No atrophy of the bilateral shoulder muscles. Normal bilateral scapulothoracic movement. Full range of motion at the bilateral upper extremities. Bilateral shoulders non-tender to palpation over the anterior, lateral, or posterior aspects. Neck non-tender to palpation. No pain noted with cervical neck flexion, extension, or rotation.
DIFFERENTIAL DIAGNOSIS: 1) Labral Tear 2) Rotator Cuff Tendinopathy 3) Suprascapular nerve palsy at the spinoglenoid notch
TEST AND RESULTS: Bilateral upper extremity EMG: On nerve conduction studies, no response obtained from the right infraspinatus, response normal at the supraspinatus when stimulating at Erb’s point. On needle EMG, 4+ fibrillations and no recruitment seen at the right infraspinatus; normal supraspinatus. Electrodiagnostic evidence suggestive of a right suprascapular nerve neuropathy selectively affecting the infraspinatus. Findings compatible with suprascapular nerve palsy proximal to or at the spinoglenoid notch.
FINAL WORKING DIAGNOSIS: Suprascapular neuropathy selectively affecting the infraspinatus due to repetitive overhead activity.
TREATMENT AND OUTCOMES: The patient was prescribed a 4-week course of physical therapy for range of motion exercises and shoulder rotator cuff muscle strengthening. She was advised to initiate a return-to-play graduated exercise program after completion of PT based on strength and tolerance to pain. The patient's pain significantly improved with PT and rest. She was able to return to competitive play within 8 weeks.