title: [Developmental changes in the Collis horizontal reaction analyzed using a three-dimensional video motion analysis system. II. Examination of upper-limb movement during the Collis horizontal reaction].
abstract: At four months old, infants of 72% challenged with the Collis horizontal reaction touch the floor with the back of their free hand. As the infants grow older, the ratio of infants that open their free hand and perform a support reaction increases from 0% to 100%. At nine months old, all infants perform this support reaction with their free hand palm-side down. To assess infant development more accurately, we used a three-dimensional video motion analysis system to evaluate upper limb movement in 38 infants (total 151 times) from 4-9 months old during the second and third phases determined by the Collis horizontal reaction. By analyzing the constituent components of upper limb movement during the Collis horizontal reaction, we assessed the usefulness of the reactions as an objective tool to measure developmental changes in infants. During the analysis, we thought to assess the speed of the upper limb reaction was respect to pronating the forearm, supporting the body with the palm down, and location of their free hand. The analysis shows that if development progresses normally and infants pronate the forearm to support the body with the palm down, the central value at which their free hand is located moves to a point under the shoulder. The results suggest that in infants four to nine months old, the Collis horizontal reaction is an excellent method to assess not only the present physical development level, but also future physical development attainment by only evaluating developmental changes of upper limb movement only.
authors.affiliation: Department of Pediatrics, Tokyo Medical University, Tokyo. n-32hiro@tokyo-med.ac.jp
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Nakajima
authors.forename: Tasuku
authors.initials: T
authors.lastname: Miyajima
authors.forename: Michiro
authors.initials: M
authors.lastname: Iiyama
authors.forename: Akinori
authors.initials: A
authors.lastname: Hoshika
mesh_terms: D002657:Child Development / Q000502:physiology*; D006801:Humans; D007223:Infant; D009048:Motor Skills / Q000502:physiology; D009068:Movement / Q000502:physiology*; D010808:Physical Examination / Q000379:methods*; D011187:Posture; D011930:Reaction Time / Q000502:physiology*; D034941:Upper Extremity / Q000502:physiology*