日常生活でよくみられる起立から歩行にいたる一連の動作解析 : 高齢者における動作スピードの影響に着目して

本研究の目的は,スピードの違いによる動作特性をバイオメカニクス解析することで,連続した起立から歩行までの動作において速く動作するための要因を調査することである.対象は,本研究課題に影響を及ぼすような疾患や障害を有さない8名の高齢男性とした.課題は,椅子から起立し5m離れた場所に設置されたブザーを取りに行くものとした.動作遂行に要する時間を規定し,速い動作と遅い動作を定義した.運動学的データは,6台のカメラとVicon512を用いて収集した.動力学的データはキスラー社製床反力計2台を用いて収集した.その結果,速い動作における一歩目遊脚期踵接地時の床反力前後成分は,遅い動作と比較して有意に高値を示した.立脚側股関節角度と膝関節角度は,一歩目遊脚側足趾離床期と踵接地期において速い動作で有意に屈曲角度が大きかった.身体重心は,遅い動作と比較して速い動作において滑らかに移動した.得られた結果は,起立動作,歩行開始動作を個々に分析しても得られなかったであろう.今後更なる研究により,高齢者や障害を持つ者の転倒を予防し,健康増進に役立つ結果が得られるものと思われる.

The purpose of this study was to investigate the kinematic and kinetic characteristics of the two speed phases of a motion and to determine the pertinent factors in the sequence of quickly standing up and initiating gait. Eight elderly male subjects, who had no disease and/or impairment that would affect the task in this study, were recruited. The test task was to stand up from a chair, walk 5 m, and then pick up a telephone on the table. We defined the difference in setting time as faster motion and slower motion. The kinematic data was obtained using a six camera Vicon 512 motion capture system. The kinetic data was obtained by using two Kistler force plates. As a result, the anterior-posterior ground reaction force was larger in the faster motion than in the slower motion at first heel strike. As for the hip and knee angle, each angle was significantly larger for the first toe off and heel strike in the faster motion. The center of gravity of the whole body moved more smoothly in the faster motion than in the slower motion. The moment of the knee joint was 1.7 times larger in the faster motion than in the slower motion. The observed effects could not be obtained by analyzing each motion of standing up and initiating gait individually. The authors believe the results in the current study will significantly help to promote the health status of the elderly and/or physically handicapped and prevent them from falling in activities of daily living.