Comparison of the strength endurance parameters for the Baltimore Therapeutic Equipment (BTE) Simulator II and the Jamar Handgrip Dynamometer

Abstract

BACKGROUND: The purpose of this study was to provide evidence regarding the Baltimore Therapeutic Equipment (BTE) Work Simulator II’s recommended grip endurance protocol. The grip endurance protocol of the BTE Simulator II has never been validated, though it has been used often for the rehabilitation of work-related injuries and other occupational dysfunctions. Without validation, the grip endurance protocol may or may not be providing skilled clinicians with appropriate evaluation results. This study evaluated a protocol comparing the BTE Simulator II to the Jamar Dynamometer to determine how the BTE compares to the Jamar device.

OBJECTIVE: To establish whether the recommended grip endurance protocol for the BTE Simulator II is comparable to the parameters established for the Jamar handgrip dynamometer.

METHODS: Data were gathered from 140 participants ages 18 to 40 at the time of the study. Participants completed protocols established for the BTE Simulator II and compared to a performance of a grip strength endurance protocol for the Jamar Handgrip Dynamometer. After establishing baseline strength levels for the participants, they were timed to see how long they could sustain a 30% maximum voluntary contraction (MVC) on each device. Sample t-tests were calculated to compare the results of the BTE Simulator II to the previously validated Jamar device.

RESULTS: A dependent sample t-test found no statistically significant difference between the times a participant sustained 30% of their maximum voluntary contraction (MVC) on the BTE Simulator II with attachment #162 versus the Jamar Dynamometer when comparing the differences of the means. This provides possible evidence of validity for the BTE endurance protocol. The independent sample t-test found no statistically significant difference between the grip endurance of the males versus the females, however, the means indicate men sustained 30% of their MVC longer than their female counterparts on the BTE.

CONCLUSIONS: The findings indicate that the 30% MVC may be a reliable baseline for grip strength endurance testing following the BTE Simulator II protocol. This suggests that the BTE Simulator II’s endurance protocol may be a useful tool to document client progression during rehabilitation after sustaining an upper extremity dysfunction. Further research is needed to validate this protocol using different populations.