P-NE022. Ulnar neuropathy in the hand: A clinical & electrodiagnostic study in 20 patients

Abstract

Introduction . Ulnar neuropathy at the wrist is less frequent than at the elbow and could be difficult to localize clinically. Electrodiagnosis can help to localize the site of the lesion along the nerve and differentiate it from other conditions like motor neuron disease. We conducted a retrospective study in patients with ulnar neuropathy in the hand between 2013 and 2020. The objective was to study the electrodiagnostic features and correlate them with clinical impression and probable aetiology. Twenty patients were diagnosed with ulnar neuropathy in the hand- due to various causes over an 8 -year period. Two patients had bilateral symptoms. The clinical reference for electrodiagnosis varied from multifocal motor neuropathy, anterior horn cell lesion to “ulnar neuropathy studies to identify site of involvement”. Seven patients had history of trauma; eleven of acute or repetitive pressure and two had a ganglion in the Guyon’s canal. Results . Using the classification devised by Wu et al. there were two patients with type I (sensory -motor at wrist) one with type II (sensory branch) seven with type III (proximal deep motor branch) and nine with type IV (distal deep motor branch) involvement. One patient with trauma had multifocal involvement of the ulnar nerve branches in the palm. History of pressure was not always forth coming and direct questions needed to be asked. Patients with ganglion cysts had history of insidious onset and chronic denervation on needle electromyography, while those with history of acute pressure related weakness presented with sudden onset symptoms and electrodiagnostic evidence of focal slowing in the motor fibres with or without acute denervation depending on the severity and duration of the pressure. Traumatic neuropathies showed electromyographic evidence of acute axonal loss and reinnervation when partial. Conclusion . Electrodiagnosis helped to localize and predict the probable cause of the ulnar neuropathy in the hand.