The objective of this observational cross-sectional study was to investigate the normal motion of the median nerve when stretched during a neurodynamic exercise. In recent years, ultrasonography has been increasingly accepted as an imaging technique for examining peripheral nerves in vivo, offering a reliable and noninvasive method for a precise evaluation of nerve movement. Transverse motion of the median nerve in the arm during a neurodynamic test was measured. A volunteer sample of 22 healthy subjects (11 women) participated in the study. Nerve displacement and deformation were assessed by dynamic ultrasonography. Excellent interobserver agreement was obtained, with kappa coefficient of .7–.8. Ultrasonography showed no lateral motion during wrist extension in 68% of nerves, while 73% moved dorsally, with statistically significant differences between sexes (ORlat = 6.3; 95% CI = 1.4–27.7 and ORdor = 8.3; 95% CI = 1.6–44.6). The cross-sectional area was significantly greater in men (3.6 mm2). Quantitative analysis revealed no other statistically significant differences. Our results provide evidence of substantial individual differences in median nerve transverse displacement in response to a neurodynamic exercise.
Jacinto Javier Martínez-Payá, José Ríos-Díaz, María Elena del Baño-Aledo, and Javier Meroño-Gallut are with the ECOFISTEM research group, Health Sciences Department, Facultad de Ciencias de la Salud, Universidad Católica San Antonio de Murcia, Spain. David García-Martínez and Ana de Groot-Ferrando are in private practice, Alicante, Comunidad Valenciana, Spain.
Address author correspondence to María Elena del Baño-Aledo at firstname.lastname@example.org.