title: Median nerve behavior at different wrist positions among older males.
abstract: The effect of wrist flexion-extension on the median nerve appearance, namely the cross-sectional area (MNCSA) and the longitudinal (D1) and vertical (D2) diameters, was investigated among older adults (N = 34). Ultrasound examination was conducted to examine the median nerve at different wrist angles (neutral; and 15°, 30°, and 45° extension and flexion), in both the dominant and nondominant hand. Median nerve behavior were significantly associated with wrist angle changes. The MNCSA at wrist flexion and extension were significantly smaller (P < .001) compared with the neutral position in both the dominant and nondominant hand. The D1 and D2 were significantly reduced at flexion (P < .001) and extension (P < .001), respectively, in both the dominant and nondominant hand. Our results suggest that a larger flexion-extension angle causes higher compression stress on the median nerve, leading to increased deformation of the MNCSA, D1, and D2 among older adults.
authors.affiliation: Department of Human Science, Graduate School of Design, Kyushu University , Minami-ku, Fukuoka , Japan.
authors.forename: Ping Yeap
authors.initials: PY
authors.lastname: Loh
authors.affiliation: Department of Human Science, Graduate School of Design, Kyushu University , Minami-ku, Fukuoka , Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Nakashima
authors.affiliation: Department of Human Science, Faculty of Design, Kyushu University , Minami-ku, Fukuoka , Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Muraki
keywords: Aging; Carpal tunnel; Median nerve behavior; Median nerve cross-sectional area; Median nerve diameter