Dylan J. Leonard, BS
3rd-Year Medical Student
University of Massachusetts Chan Medical School
Worcester, Massachusetts, United States
Faren H. Williams, MD, MS
Physiatrist, Professor
UMass Chan Medical School
Worcester, Massachusetts, United States
77-year-old man presenting with slowly progressive right median motor and ulnar sensory neuropathy possibly related to radiation plexitis.
Case Description:
The patient presented to physiatry with progressive numbness of the right ring/little fingers and decreased pincer grasp over months. He had already undergone ulnar nerve transposition without benefit.
Three electrodiagnostic studies (EDX) over several years revealed decreased right ulnar sensory and very low right median motor amplitudes without significant median sensory changes nor ulnar motor changes at the elbow. During this time, he had a carpal tunnel release, ulnar nerve transposition (later revised), transfer of the anterior interosseus neve (AIN) to the motor branch of the ulnar nerve, and median neuroplasty without improvement. Updated EDX demonstrated no median motor response and profound pincer weakness with thenar atrophy.
Subsequent cervical spine MRI demonstrated degenerative changes with severe canal stenosis, but no cord signal changes at multiple levels. The patient then provided history of neck radiation therapy in 2005 for squamous cell carcinoma which, alongside his EDX, was concerning for radiation plexitis.
Discussions:
Three separate electrodiagnostic studies demonstrated that this patient had median motor neuropathy, not a carpal tunnel syndrome, and a decreased ulnar sensory response with no focal ulnar motor changes at the elbow. Despite these findings, he underwent four surgeries with no improvement in his median motor function or ulnar sensation.
After discovering that his condition may be related to radiation plexitis, he had two surgical consultations with only one recommending cervical surgery. He is now considering a tendon transfer to partially restore his motor function in the hand. This procedure would not address his sensory symptoms.
Conclusions:
This case demonstrates the importance of obtaining a detailed history and physical exam to appropriately interpret electrodiagnostic studies and advise the surgeon regarding efficacy of treatment.
