Masseter reflex in childhood and adolescence.
We report normative data of masseter reflex from a group of 54 children 2-16 years of age. For statistical analysis, the patients were divided into five age groups: 2-4, 5-7, 8-10, 11-13, and 14-16 years of age. A tap to the chin, using a hammer with a trigger device, elicited the masseter reflex. The response was recorded by surface electrodes. The onset latency and peak-to-peak amplitude of the averaged curve of eight reflex responses were measured. The reflex response could be recorded in all children and adolescents of all groups. The mean latency shortened from age 2 to 7 and was stable at the age of 8 years. As a sign of maturation, the increase of amplitude corresponded to the shortening of latency and was also stable at the age of 8 years. Abnormal side differences in latency of 0.9 ms (age group 2-4 years), 1.1 ms (age group 5-7 years), and 0.8 ms (age group 8-16 years) were evaluated. An amplitude ratio (lower amplitude divided by higher one) above 0.33 was calculated as normal.
Koehler
Jürgen
J
Department of Neurology, Johannes Gutenberg University Mainz, Mainz, Germany.
Hölker
Cordula
C
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004576:Electromyography / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008406:Masseter Muscle / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D012018:Reflex / Q000502:physiology*; D018709:Statistics, Nonparametric