Electrophysiologic Features of Radial Neuropathy in Childhood and Adolescence

Publication date: Available online 31 January 2018
Source:Pediatric Neurology
Author(s): Ioannis Karakis, Sofia Georghiou, H. Royden Jones, Basil T. Darras, Peter B. Kang
Objective: To analyze clinical and electrophysiologic patterns of nerve injury in pediatric radial neuropathy (PRN). Methods: Retrospective analysis on 19 children and adolescents with PRN. Results: The mean subject age was 12 years (range 1 month to 19 years), 56% were female, and 53% had traumatic etiologies. Weakness in the finger and wrist extensors was the prevailing complaint (82%). Predominant localization was at the posterior interosseous nerve (PIN) (37%), followed by the radial nerve below the spiral groove (32%), the radial nerve at the spiral groove (26%) and the radial nerve above the spiral groove (5%). Extensor indicis proprius (EIP) compound muscle action potential (CMAP) amplitude was reduced in 86% of cases when tested, with a median axon loss estimate (MAXE) of 78%. The radial sensory nerve action potential (SNAP) amplitude was reduced in 53% of all cases, and in 83% of cases affecting the main radial trunk with a MAXE of 100%. For cases affecting the main radial trunk, there was a high correlation of EIP MAXE and radial SNAP MAXE (r=0.72, p=0.02). Neurogenic changes were seen in the EIP, extensor digitorum communis, extensor carpi radialis and brachioradialis in 88%, 94%, 60% and 44% of cases respectively. Pathophysiology was demyelinating in 10%, axonal in 58% and mixed in 32%. Conclusions: In contrast to adults where localization at the spiral groove predominates, pediatric cases are commonly localized at the PIN or the distal main radial trunk. Significance: PRN is frequently of traumatic etiology and axonal pathophysiology.



http://ift.tt/2Esc7Qb