INTRODUCTION: Tests that measure the maximum grip strength (GS Max) and hand dexterity as the Nine Hole Peg Test (9-HPT) and the Jebsen & Taylor Hand Function Test (JTHFT) are commonly used to assess hand function (HF). However, GS Max may be questioned regarding its validity because we rarely exert maximum grip force to perform everyday manipulation tasks. To explore GS Max validity we investigated the relation between GS Max and tests that assess hand dexterity. Also, we tested the relationship between tests used to evaluate hand dexterity. AIM: To assess the relationship between GS Max and the performance in JTHFT and the relationship between the performance in 9-HPT and JTHFT. METHOD: Thirty-six healthy young adults (18 males and 18 females) performed the JTHFT followed by the 9-HPT and the GS Max test, with their dominant and non-dominant hands. Pearson's correlation analyses were performed between them. RESULTS: Moderate negative correlation between the GS Max and the JTHFT was revealed (r < - 0.74), indicating that stronger individuals perform the JTHFT faster. Also, results revealed a weak correlation between the performance in 9-HPT and the JTHFT, and only for the non-dominant hand. CONCLUSION: GS Max can be used as an indicator of HF, but it should be used prudently because this variable does not represent all aspects related to hand force control and coordination during object manipulation and tasks related to digits dexterity. Also, both JTHFT and 9-HPT, that are used to assess HF, indicate distinct aspects related to the individual's manipulation ability.
Hand function; Dexterity; Muscle strength dynamometer
