Quantitative Value of Therapist's Gentle Pull for Pinch Strength Test

摘要

The pinch strength against external resistance can be evaluated using the pincer grasp component of Fugl Meyer Assessment (FMA) to determine the level of pinch impairment after a stroke. In the pincer grasp component, the therapist would apply a gentle pull with a resistance equivalent to a Manual Muscle Test (MMT) score of 4/5. However, the qualitative description of 4/5 MMT is subjective which may lower intra-rater and inter-rater reliability. The present study aims to provide a quantitative value of the therapist's gentle pull rather than the qualitative description. Four therapists were instructed to apply a gentle pull (4/5 MMT) using their index-thumb finger (in a tip-to-tip pinch) with a standardized body posture. The pulling force load cell was used to measure the pulling force produced during the gentle pull. The results showed that the therapists exerted a mean gentle pull (4/5 MMT) of 6.34±0.98 N. In addition, the therapists showed excellent reliability and acceptable repeatability in applying the gentle pull (4/5 MMT) for three trials.