乳幼児期における全身発育および股関節発育と運動機能発達との関係

抄録

For the purpose to study the influence of the physical growth on the development of activity, 2063 infants were examined during one year from April of 1956 at random by sex, month-age, birth-month, from the infants between the ages of 1 and 20 months who had been registered at a certain health center in Aichi prefecture. The samples were taken measurements of their height, weight and taken the direct X-ray photographs of their hip-joints, and tested for their activities. After a severe selection 1230 X-ray films (600 of boys and 630 of girls) out of 2063 were finally taken mesurements of several parts of the hip-joints. Stochastical analysis on the measurements of these samples brought the following results.
(1) The infants who got to higher stages of motor development than the average were found to have greater heights, weights and hip-joints than those who failed to get in the same chronological age.
(2) The acquisition percentages of the activity associated with the measurements of the hip-joints, regardless of the parts measured and the items tested,
a) represented an S-shaped curve,
b) arised rapidly higher near the measurements of hip-joints at which 50% of the infants had acquired the activity, and
c) became to show a slow raise after that point and showed this tendency more obviously in the higher stages of motor development.
(3) No sexual differences were found in the measurements of hip-joints at which 50% of the infants had acquired the activity.
(4) The infants who could stand up and those who could walk were clarified to have a greater growth not only of standing height, body weight but of the breadth of the hip-joints than those who could not respectively in the same chronological age.