The effect of thumb interphalangeal joint position on strength of key pinch.
Thirty normal male and female subjects participated in a study to determine if the interphalangeal (IP) joint position of the thumb affects the outcome of lateral pinch strength tests. The subjects performed strong lateral pinch for three trials with both the thumb IP joint flexed and extended. The results showed that when flexion of the thumb IP joint was used, female subjects showed an increased strength of 30% for the right side and 28% for the left side compared to when they used extension of the thumb IP joint during lateral pinch. The male subjects showed increased strength of 36% for the right side and 38% for the left side when flexion versus extension of the thumb IP joint was used. IP joint position of the thumb was found to significantly affect the results of lateral pinch strength tests.
D000328:Adult; D000368:Aged; D005384:Finger Joint / Q000502:physiology*; D006801:Humans; D008875:Middle Aged; D013933:Thumb / Q000502:physiology*