The injured upper extremity and the JAMAR five-handle position grip test

Niebuhr and Marion (Am J Phys Med Rehab 1990;69:96-101) recently presented a study that utilized healthy subjects who were able to control the amount of force exerted during submaximal grip strength efforts. Stokes (J Occup Med 1983;25:683-684) proposed that a true weakness of grip can be distinguished in the injured upper extremity from a feigned effort that yields a flat horizontal type of curve. The purpose of this study was to evaluate the five- handle position JAMAR grip test in an injured population and compare the curves produced with a group of healthy subjects. We found that the patients with well-documented pathology produced a curve that was similar in shape to the healthy group; however, the curve on the injured extremity was reduced in force output.