Estimation of Normal H-Reflex in Flexor Carpi Radialis Using Meta-analysis

J Korean Assoc EMG Electrodiagn Med 2002;4(2):79-87.
Published online May 10, 2002.

Abstract

Objective : H-reflex is noted in the flexor carpi radialis muscle of the upper limb and can be used in the diagnosis of C6 and C7 radiculopathies. Despite a number of normative studies of FCR H-reflex, each laboratory have one’s own test method and normative database. Obvious difficulties arise in attempting to compare data from one laboratory to another. there is a need to established a standardized test method with normal references. We initiated this study to overcome these difficulties. Method : We searched through 18 sources, which had been previously published from 1975 to 1999, concerning FCR H-reflex. The search provided a common test method using all 18 sources and side to side difference (latency, amplitude) and obtained a normal reference value of latency through the metaanalysis technique by researching 7 sources stated normal reference values. Results : 1) The most common test method on surface recording technique used active surface electrode which was applied to over about one-third of the distance between the medial epicondyle and the radial styloid. the stimulation site was median nerve on cubital fossa. the stimulation duration was 0.5 1.0 msec. the stimulation frequency was 0.2 pps. 2) From a meta-analysis of data on 3 domestic articles, estimated latency which were examined at forearm 1/3 site was 13.9 1.9 msec and from a meta-analysis of data on 4 articles outside the country, estimated latency which were examined at forearm 1/3 site was 15.7 1.4 msec. Conclusion : We present most common test method and the standard reference value through metaanalysis. This values is helpful to increase accuracy for diagnosing C6 and C7 radiculopathies.

Key Words: Meta-analysis, Flexor carpi radialis H-reflex, Normative data