REFERENCE VALUES FOR HANDGRIP STRENGTH AMONG HEALTHY ADULTS IN NIGERIA

Handgrip strength (HGS) measurements provide an objective index of the functional integrity of the upper extremity. Motivated by the paucity of reference values for HGS for an African population, this study sought to establish reference values for HGS in healthy Nigerian adults. The HGS of 745 (409 male and 336 female) healthy volunteers from the ages of 20-70 years was measured using a Takei Kiki Kogyo handgrip dynamometer in accordance with the American Society of Hand Therapists protocol. Men exhibited higher HGS than that in women in both dominant (35.2 kilogram force [kgf] vs. 24.9 kgf) and non-dominant (31.6 kgf vs. 22.8 kgf) hands. Using percentile values cut points, less than 25(th) (poor grip strength), 25th-75th (moderate grip strength), and > 75(th) (good grip strength) percentile were <29.0 kgf, 29.0-34.0 kgf, and > 34.0 kgf, respectively, for the dominant hand and < 24.0 kgf, 24-36.0 kgf, and > 36.0 kgf, respectively, for the non-dominant hand. These findings suggest that males have a significantly higher HGS than females. HGS decreases with increasing age for both dominant and non-dominant hands. The reference values derived in this study would be useful in assessing impairment in functional ability of the upper extremities in both healthy and patients' populations.