Rare Case of Musculocutaneous Neuropathy in a Professional Baseball Pitcher

Musculocutaneous nerve injury is a rare condition.

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.

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.