Assessing the Reliability of Ultrasound Imaging to Examine Radial Nerve Excursion

Ultrasound imaging allows cost effective in vivo analysis for quantifying peripheral nerve excursion. This study used ultrasound imaging to quantify longitudinal radial nerve excursion during various active and passive wrist movements in healthy participants. Frame-by-frame cross-correlation software allowed calculation of nerve excursion from video sequences. The reliability of ultrasound measurement of longitudinal radial nerve excursion was moderate to high (intraclass correlation coefficient range = 0.63-0.86, standard error of measurement 0.19-0.48). Radial nerve excursion ranged from 0.41 to 4.03 mm induced by wrist flexion and 0.28 to 2.91 mm induced by wrist ulnar deviation. No significant difference was seen in radial nerve excursion during either wrist movement (p > 0.05). Wrist movements performed in forearm supination produced larger overall nerve excursion (1.41 ± 0.32 mm) compared with those performed in forearm pronation (1.06 ± 0.31 mm) (p < 0.01). Real-time ultrasound is a reliable, cost-effective, in vivo method for analysis of radial nerve excursion.