Quantitative abductor pollicis brevis strength testing: reliability and normative values.

We conducted this study to establish reliability and normative values for abductor pollicis brevis strength. A portable microprocessor-controlled hand-held device was used for testing. Twelve healthy subjects were used for intrarater and interrater reliability testing. Intraclass correlation coefficients were 0.92 for intrarater testing and 0.89 for interrater reliability. Normative values for abductor pollicis brevis strength are presented by gender and age from the test results of 297 volunteers (121 men and 176 women; age range, 20-59 years) with at least 30 subjects in each subgroup. Abductor pollicis brevis strength was significantly greater in the men than in the women in all age groups. No significant differences were found related to age, side, or dominance. The results suggest that quantitative muscle testing produces consistent values for abductor pollicis brevis strength that remain fairly constant in patients aged 20 to 59 years.