Grasping Naturally Versus Grasping With a Reacher in People Without Disabilities: Motor Control and Muscle Activation Differences
By Maitra, Kinsuk K.; Philips, Katherine; Rice, Martin S.; American Journal of Occupational Therapy, Vol. 64, No. 1, pp. 95-104Publication Date: January/February 2010
Study investigated motor control and muscle activation when reaching for and grasping objects with a reacher compared with the unaided hand. In a repeated measures counterbalanced design, 41 participants aged 18 to 55 years, without disabilities and with no previous experience using a reacher, were randomly assigned to a sequence of 4 conditions: reaching and grasping (A) a golf ball, (B) a baseball, (C) a small Rubik’s Cube, and (D) a large Rubik’s Cube. A total of 12 trials were carried out, each using the reacher and the natural grasp. Movements of the wrist and fingers were recorded using a three-dimensional Qualisys camera system for assessing reach and grasp. Muscle activations from finger and arm flexors and extensors were recorded by surface electromyography. Results revealed participants exhibiting a smaller grasp aperture, longer reaching time, and more muscle activity when using the reacher. The authors conclude that, as efficient motor control requiring both time and practice is needed to use a reacher successfully, therapy clients presented with reachers without sufficient time to develop motor skills unique to reacher use may be more likely to abandon this assistive device or fail to benefit from its function.
Published by: American Occupational Therapy Association, Inc. (AOTA) (Website:http://www.aota.org)
