Quantitative assessment of elbow flexion by handheld dynamometry in brachial plexus palsy.

Abstract

The purpose of this study was to assess the relative and absolute reliability of a handheld dynamometer when used for examining elbow flexion power in patients with brachial plexus palsy. The assessment of the intra-rater and inter-rater reliability coefficients for the handheld dynamometer was done using the stationary Kin-Com® dynamometer as the reference standard. We determined the measurement errors and checked the systematic biases of the handheld dynamometer. The inter-rater and intra-rater reliabilities of the handheld dynamometer had a very high intraclass correlation coefficient. The values of handheld dynamometer readings had a high correlation to Kin-Com® readings. The Medical Research Council grading was a comparatively inaccurate method for quantitative assessment of motor power. We conclude that a handheld dynamometer measurement is more precise and reliable than the Medical Research Council grading for measuring recovery of elbow flexion in patients with brachial plexus palsy. Level of evidence: III.