Deformation of the median nerve at different finger postures and wrist angles

Ping Yeap Loh; Wen Liang Yeoh; Hiroki Nakashima; Satoshi Muraki

doi:10.7717/peerj.5406

Deformation of the median nerve at different finger postures and wrist angles

PeerJ. 2018 Aug 9:6:e5406. doi: 10.7717/peerj.5406. eCollection 2018.

Authors

Ping Yeap Loh¹, Wen Liang Yeoh², Hiroki Nakashima¹, Satoshi Muraki¹

Affiliations

¹ Department of Human Science, Faculty of Design, Kyushu University, Fukuoka, Japan.
² Department of Human Science, Graduate School of Design, Kyushu University, Fukuoka, Japan.

Abstract

Background: The objective of this study was to evaluate the changes of the median nerve cross-sectional area (MNCSA) and diameters of the median nerve at different finger postures and wrist angles.

Methods: Twenty-five healthy male participants were recruited in this study. The median nerve at wrist crease was examined at six finger postures, and repeated with the wrist in 30° flexion, neutral (0°), and 30° extension. The six finger postures are relaxed, straight finger, hook, full fist, tabletop, and straight fist.

Results: The main effects of both finger postures and wrist angles are significant (p < 0.05) on changes of the MNCSA. Different finger tendon gliding postures cause a change in the MNCSA. Furthermore, wrist flexion and extension cause higher deformation of the MNCSA at different finger postures.

Discussion: The median nerve parameters such as MNCSA and diameter were altered by a change in wrist angle and finger posture. The results may help to understand the direct biomechanical stresses on the median nerve by different wrist-finger activities.

Keywords: Carpal tunnel; Median nerve cross-sectional area; Median nerve diameters; Tendon gliding exercise.

Grants and funding

This work is supported by JSPS KAKENHI Grant Numbers JP16J01964 and JP18K17969. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.