title: Detection of submaximal effort with computer-assisted grip strength measurements.
abstract: The purpose of this study was to establish a simple observation to help in distinguishing patients who are giving their maximal effort during computer-assisted grip strength measurements from those who are not. Preliminary observations had suggested that maximal effort with this grip-strength device was characterized by greater force in the radial digits than the ulnar digits and a small variability in force between individual grasps. These observations were then prospectively analyzed in the following groups: (a) 178 assembly workers tested during a routine screening at a computer manufacturing company and during pre-placement physicals; (b) 196 workers with a hand injury or cumulative trauma disorder who were seeking consultation for medical treatment; (c) 55 workers with a hand injury or cumulative trauma disorder being measured to determine their return to work status or impairment rating; and (d) 58 asymptomatic volunteers. The volunteers were instructed to perform the maximal grip in the same fashion as the other groups and then to repeat the test exerting a submaximal effort they estimated to be 50% of their own maximal effort. The results of this study demonstrated that there is a highly significant association, P < 0.001, between the presence of a "total pattern" (radial over ulnar force being less than 1.0, unilateral grip variation greater than 15%, and difference between the left and right grip variation greater than 5%) and the presence of submaximal effort during grip-strength measurements.
authors.affiliation: Occupational Medicine Consultants, Ltd., Minneapolis, Minn., USA.
authors.forename: M D
authors.initials: MD
authors.lastname: Mitterhauser
authors.forename: V L
authors.initials: VL
authors.lastname: Muse
authors.forename: A L
authors.initials: AL
authors.lastname: Dellon
authors.forename: T C
authors.initials: TC
authors.lastname: Jetzer
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D003201:Computers; D004185:Disability Evaluation; D005260:Female; D006230:Hand Injuries / Q000503:physiopathology*; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D008297:Male; D011446:Prospective Studies