Presumption of Calf H reflex Latency with Regression Analysis

J Korean Assoc EMG Electrodiagn Med 2006;8(2):109-113.
Published online May 10, 2006.

Abstract

Objectives: This research was aimed to improve diagnostic effectiveness of calf H reflex in patients with S1 radiculopathy, and to analyze the relationship between age, leg length, conduction velocity of tibial nerve, height and H latency. Methods: This research was conducted on 50 normal subjects who had no musculoskeletal and neurologic involvement. Leg length and height were measured. Skin temperature between site of stimulation and that of electrode was measured. Conduction velocity of tibial nerve and H reflex onset latency in calf muscle were measured. We analyzed Pearson’s correlation coefficients for relationship between H reflex onset latency and other parameters including height, conduction velocity of tibial nerve, age and leg length. And regression analysis was performed for forming equation of upper normal value of H latency with these parameters. Results: All the parameters had correlation with H latency and the equation, upper normal value of H latency=16.0+0.12×height (cm)-0.16×conduction velocity of tibial nerve (m/sec) was obtained with regression analysis. Conclusion: The H latency in calf muscle was correlated more with height and conduction velocity of tibial nerve. And the obtained regression equation might be used as more effective tool for the diagnosis of S1 radiculopathy.

Key Words: H reflex, S1 radiculopathy, Electrodiagnosis