Neurogenic Thoracic Outlet Syndrome Presenting as Chronic Elbow Pain After Obstacle Course

Abstract

HISTORY: A 20-year-old female US Naval Academy freshman sustained a left elbow injury after repetitive shoulder abduction movements while completing a required obstacle course. She denied specific trauma, including a fall. There was no numbness, tingling, or radiation of pain. Five days later, she reported her left elbow pain to her physician. Originally diagnosed with an elbow contusion versus epicondylosis, the patient’s progressive left elbow pain lasted for more than 6 months when she developed ulnar dysesthesias in her hand. PHYSICAL EXAMINATION: Examination revealed diffuse elbow tenderness with swelling. Normal neurovascular examination was demonstrated. Elbow strength and range of motion were normal. Neck and shoulder exams demonstrated no abnormalities. Swelling resolved in one week. Exam remained unchanged for several months before she developed ulnar distribution pain. Then, an Allen test reproduced and worsened her elbow pain and neurologic symptoms. DIFFERENTIAL DIAGNOSIS: 1. Elbow Contusion 2. Chronic Regional Pain Syndrome 3. Intraarticular Body, Elbow Fracture 4. Brachial Plexopathy 5. Thoracic Outlet Syndrome TEST AND RESULTS: Left elbow anterior-posterior, lateral radiographs: — no acute osseous abnormality Left elbow MRI: — likely resolving bony contusion of radial head without evidence of fracture CT Left Elbow: —normal evaluation of the left elbow EMG left upper extremity: —normal electrodiagnostic study Left brachial plexus MRI: —normal left brachial plexus Chest MRI, with contrast: —findings consistent with thoracic outlet syndrome localized to costoclavicular space Left upper extremity venogram: —no evidence of venous occlusion or compression FINAL/WORKING DIAGNOSIS: Neurogenic Thoracic Outlet Syndrome TREATMENT AND OUTCOMES: 1. Relative rest, ice, compression and NSAIDs for 4 weeks without improvement. 2. Activity modification and trial of acupuncture demonstrated minimal improvement in presenting elbow pain. 3. Left scalene block with complete relief of symptoms, indicating neurogenic thoracic outlet syndrome. 4. Partial left first rib resection with resolution of chronic left elbow pain and ulnar nerve dysesthesias. 5. Range of motion, shoulder, and neck strengthening exercises started gradually 6 weeks post-surgery.