P230 Ulnar epineural discontinuity and electrophysiological changes in a young girl following ulnar fracture

Abstract

Objectives Electrophysiologic evaluation of traumatic peripheral nerve lesions can be complicated, especially in children where the given diagnosis can have dire consequences especially if not accurate. Method electrophysiological and sonographic consecutive examinations during a timelapse of 2 years (4 examinations). Results A 10 year old girl developed a severe ulnar neuropathy following a fracture of both forearm bones. Electrophysiology resembled complete denervation without any motoric or sensory answers. EMG revealed spontaneous activity in the interosseous dorsalis 1 muscle in the affected arm. Sonography visualized the nerve with an epineural defect but in continuity. We followed the girl in a timespace over 2 years with a total of 4 examinations. As the epineural defect diminished the electrophysiologic changes recovered. At the 4 examination the sonographic appearance was normalized except a slight neuroma at the lesion site. Discussion Decision making following traumatic nerve lesions relies heavily on electrodiagnostic testing. In this case we have shown that an epineural defect can “mimick” nerve discontinuity electrophysiologic. Sonography revealed the nerve in continuity and the nerve function slowly regained following the recovery of the epineurium. Conclusions Epineural defects can have an electrophysiological appearance resembling complete denervation in the recovery period. If sonography shows nerve continuity a conservative approach could be recommended. Significance Sonography can help along with electrophysiology in differentiating between severed nerves and nerve changes electrophysiologically resembling complete denervation. The case could argue that sonography should be performed in all traumatic nerve lesions.