Rare Case of Musculocutaneous Neuropathy in a Professional Baseball Pitcher

Abstract

Introduction: Musculocutaneous nerve injury is a rare condition.

Case report: We present a case of musculocutaneous neuropathy in a previously healthy 24-year-old professional baseball pitcher who began experiencing right arm weakness and forearm paresthesia a week after switching from a starter to a relief pitcher. Ultrasound confirmed entrapment of the coracobrachialis. Magnetic resonance imaging showed a hyperintense T2 fluid signal within the nerve, and electromyography demonstrated prolonged latency of motor and sensory function, along with evidence of active axonal injury. He experienced minimal symptom relief with a course of oral steroids and physical therapy. Subsequent steroid injection around the musculocutaneous nerve at the level of the coracobrachialis resulted in significant symptom improvement.

Conclusion: This case illustrates the importance of clinicians maintaining a high suspicion for rare peripheral neuropathies in elite athletes and remaining knowledgeable about appropriate diagnostic work-up and treatment.

Keywords: Musculocutaneous nerve; coracobrachialis; musculocutaneous neuropathy; throwing athlete.