DEVELOPMENT AND EVALUATION OF A NEW INSTRUMENT TO QUANTIFY THE DEEP TENDON REFLEX IN THE ADULT AND ELDERLY

Abstract

Introduction: Deep tendon reflex (DTR) is routinely used to evaluate the nervous system. Majority of the available devices to measure DTR response are not easily accessible, highly cumbersome, and capital intensive. This study sought to develop and evaluate a less cumbersome, cost effective and easily accessible instrument that can objectively quantify DTR.   

Materials and Methods: A simple DTR device was fabricated and then evaluated. A total of 74apparently healthy individuals and five hemiplegic patients participated in this cross-sectional analytical study. Hemiplegic participants were to determine the criterion-related validity of the device. Of the apparently healthy participants, 69were assigned into three groups according to their age. Angle of knee excursion (patellar DTR response) was measured using the newly developed DTR device. Jendrassik maneuver was introduced in participants who failed to respond to the initial patellar tendon tapping.Pearson correlation was used to determine relationship between variables at P <0.05.

Result: The device demonstrated good face and criterion-related validity coupled with high test-retest and inter-rater reliability with coefficient of 0.74 and 0.86 respectively. There was no significant difference between the patellar tendon response for the right and left lower limbs.(p>0.05).Similarly, sex and age has no significant effect on the patellar tendon reflex response respectively (p>0.05).

Conclusion: The newly developed instrument is less expensive and less cumbersome, and was found to be valid. Findings of the study are comparable with previous study that age, sex, and handedness had no significant effects on DTR response. It is therefore recommended for the use of clinicians.