J Korean Neurol Assoc.  1990 Dec;8(2):264-270.

Vibratory Inhibition Index of H Reflex, H/M and F/M Ratios in Patients with Spastic Weakness

• Hong SB
• Kim SH
• Na DL
• Lee KW
• Roh JK
• Lee SB
• Myung HJ

Abstract

The vibratory inhibition index(V.I.I.) of H-reflex, H/M(mean H-reflex amplitude / mean M wave amplitude) and F/M(mean F wave amplitude / mean M wave amplitude) ratios were measured in patients of hyperreflexia with or without spasticity. These data were compared with age-matched control subjects. In comparison to normals, V.I.I. And F/M ratios were increased at statistically significant levels(versus normal : V.I.I. P<0.001, F/M p<0.005) in patient group. And V.I.I.'s were inclined to be correlated with F/M ratios without statistical significance(r=0.27, p=0.21). H /M ratios showed no significant difference between patient and control groups. In these patients, the normal significant correlation between mean F wave amplitude and M wave amplitudes was maintained(p<0.01). F/M ratios were negatively correlated with rnotor nerve conductoion velocity(r= -0.72, p<0.01).These results indicate that V.I.I. And F/M ratios increase in patients with hyperreflexia and/or spasticity. Although mechanisms differ, the data are consistent with a similar physiological responses of H-reflex and F wave to spasticity.

MeSH Terms

H-Reflex*
Humans
Muscle Spasticity*
Reflex, Abnormal