IngentaConnect A Study of the Effect of a Wrist Splint on Extrinsic Plexor and A...

Authors: Perez-Balke, Graciela; Buchholz, Bryan

Source: Human Factors and Ergonomics Society Annual Meeting Proceedings, Posters , pp. 958-958(1)

Publisher: Human Factors and Ergonomics Society

Abstract:

wrist splints have recently gained popularity as a control for work stressors associated with musculoskeletal disorders such as carpal tunnel syndrome. Awkward postures, force, and repetition have been identified as work stressors. The goal of this study was to determine the effect of the use of a rigid wrist splint on force, via surface electromyography (EMG) during a repetitive pick and place task. Extrinsic flexor EMG (EF) and anterior deltoid EMG (AD) increased 37.4% (± 21.8) and 12.5% (±18.5), respectively, with the use of the splint (p< 0.01). In addition, peak power grip strength (PGS), measured with a dynamometer, decreased an average of 18.4%, with the use of the splint. Women experienced a 3.5− fold greater percent decrease in PGS as compared with men. There were no significant gender differences for percent change in mean EF. conversely, percent change in AD was twice as high for males as compared with females. In addition, percent change was five times greater for five male subjects who improved their PGS with the splint as compared with the fifteen subjects whose PGS decreased with the use of the wrist splint. In conclusion, although the splint limited motion of the wrist, EF and AD significantly increased during a pick and place task. In addition, subjects whose PGS increased with the use of the splint experienced the greatest percent increases in anterior deltoid muscle activity. This research suggests that although splints limit posture they may increase the muscle activity of the upper extremities during repetitive tasks that require non-neutral postures.

A Study of the Effect of a Wrist Splint on Extrinsic Plexor and Anterior Deltoid Electromyography During a Pick and Place Task