Assessment of Deep Tendon Reflexes by Motion Analysis: A Preliminary Study

Abstract

The deep tendon reflex responses are judged by clinicians through visual observation with great variations between different examiners leading to high possibilities of errors. This study proposed an alternative approach to quantify the deep tendon reflex responses. In the preliminary stage, the motion analysis system was used to collect quantitative data for patellar tendon reflex, one of the deep tendon reflex obtained in human. A reflex hammer holder was built in the project followed by patellar tendon reflex data collection and analysis using the motion analysis system. Patellar tendon reflex was tested in a group of healthy subjects consisted of 28 males and 22 females. All tests were performed in the Motion Analysis Laboratory, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia. The tests were applied on both the left and right knee, by tapping on the tendon using 3 ranges of force. The subjects were also tested by a reinforcement technique called the Jendrassik maneuver with the same strength applied for normal patellar tendon reflex. The results showed that male subjects exhibited greater responses compared to females at higher tapping force. Comparison of reflex responses between the left and right knee was not significant. Analysis of responses with different levels of tapping force showed that high tapping force produced greater patellar tendon reflex.