Left Upper Trunk Plexopathy in a Division 1 College Football Player: A Case Report

Case Diagnosis: A 22-year-old male Division 1 football player experiencing left upper extremity weakness found to have a left upper trunk plexopathy.

Case Description or Program Description: Initial injury was obtained when an opponent forced the patient’s neck to the left. He had immediate pain shooting down his left arm and into his forearm. Injury was not reported and he continued to play. Over the course of the next 5 weeks, he had repeated injuries to the left neck with similar symptoms. He was evaluated by medical staff and a cervical MRI revealed diffuse mild discogenic change and facet arthropathy. MRI brachial plexus revealed abnormal signal within the C5 root and the proximal superior trunk most likely represent low-grade posttraumatic injury. He was then referred to physiatry for nerve conduction studies/electromyography (NCS/EMG) testing. Physical exam pertinent positives were: trace response on left biceps reflex testing, 4+ muscle strength testing in shoulder abductors, elbow flexors, and 5- in elbow extension. NCS revealed an increased peak latency of the left lateral antebrachial cutaneous as well as a 50% reduction in amplitude when compared to the right. The left superficial radial nerve also saw a reduction in amplitude of 33% compared to the right. EMG revealed 1+ insertional activity in the biceps, anterior deltoid, and posterior deltoid. In addition, 1+ fibrillation potentials and positive sharp waves (PSW) were seen in the anterior deltoid. 2 + PSWs and reduced full interference pattern were seen in the left supraspinatus.

Setting: Outpatient PM&R clinic

Assessment/Results: NCS/EMG revealed electrodiagnostic evidence of a left upper trunk plexopathy with axonal loss. Patient reported that his left shoulder and proximal arm strength were improving. Recovery prognosis was good, and patient was cleared to return to non-contact activity but avoid exercises that would apply pressure or stretching to neck. 3-6 month follow up recommended to evaluate for signs of re-innervation.

Discussion (relevance): This is a classic example of repeated neurologic injury in an athlete advancing from demyelination to axonal damage.

Conclusions: Progress is being made in identification and treatment of concussion in athletics, but all neurologic injuries should be reported and acted upon promptly to avoid continued insult and long-term deficits in athletes.