医療現場に勤務する看護師を対象としたボディメカニクス学習教材の活用と評価

Abstract

背景 看護師の職業性腰痛は深刻であり，効率よく腰部負担の少ない動作を行うためにボディメカニクスを適切に活用することが求められる。しかし，ボディメカニクスの知識や技術，認識不足のために，多くの看護師が日常業務の中で前傾姿勢など腰部負担のかかる動作を行っているのが現状である。 目的 本研究では，医療現場に勤務する看護師を対象として，ボディメカニクス活用への意識向上および看護動作時の姿勢改善を目ざして開発したボディメカニクス学習教材の活用と評価を行うことを目的とした。 方法 1.本学習教材の概要:腰部に負担がかかる危険な前傾姿勢角度をリアルタイムまたは再生時に表示する。なお，腰部にかかる関節モーメントの算出などから前傾姿勢における危険角度40°と定めた。2. 方法 : 2009年8月，研究の趣旨に賛同が得られた32名の看護師を対象とした。評価方法は，対象者に本学習教材の姿勢計測センサを装着した後，日常的に医療現場で実施しているベッドメーキング動作を以下の設定1～3の順に実施し，前傾姿勢角度データの比較を行った。設定1 : 普段通りの動作，設定2 : 適切なベッド高(身長比45%)での動作，設定3 : 本学習教材を活用して客観的評価した後の動作とする。分析は， SPSS16.0 for Windowsを用いてWilcoxonの符号付き順位検定を行い，本学習教材活用の有効性を角度変化から検証した。また，本学習教材活用前後に意識調査を実施した。内容は，ボディメカニクスおよび本学習教材活用における意識とした(5件法)。 結果 設定1では，前傾姿勢角度の平均は55.6±14.7°と最も高く，腰部負担のかかる危険角度域となっていた。設定2では43.2±11.5°であり，普段の動作より有意に減少が認められたものの腰部に負担がかかる危険域の角度であった。設定3では，前傾姿勢角度は有意に改善され28.0±11.3°であった。また，本学習教材活用によって「ボディメカニクスを今後活用していきたい」という看護師が4.5±0.7点から4.8±0.4点に有意に増加した (p<0.01)。 結論 看護師を対象として，ボディメカニクス学習教材の活用と評価を行った結果，ボディメカニクス活用への意識向上と看護動作時の姿勢改善が認められた。今後も継続研究を行い，本学習教材活用の有効性および看護師の腰痛予防への効果を検証する。

Background Occupational lower back pain is a serious problem among nurses, and appropriate application of body mechanics is important for enabling efficient actions with minimal burden on the lower back. However, at present many nurses routinely perform actions that place a burden on the lower back, such as forward leaning, due to lack of body mechanics techniques as well as knowledge and awareness of body mechanics. Objective The objective of the present study was to apply and evaluate a body mechanics learning material developed for the purpose of increasing the awareness of body mechanics and improving posture during nursing actions, using nurses working in medical settings as subjects. Methods 1. Overview of the present learning material: Dangerous angles of forward leaning at which a burden is placed on the lower back are displayed in real-time or on replay. Dangerous angles of forward leaning were defined as 40 based on calculation of the joint moment on the lower back and other data. 2. Methods: Subjects were a total of 32 nurses who consented to participate in the study in August 2009. After attaching the posture measurement sensors of the present learning material to subjects, subjects were instructed to perform bedmaking, an action they routinely perform at work, under three settings (1-3) in the following order. Setting 1: Normally performed action, Setting 2: Action performed at a suitable bed height (45% of body height), Setting 3: Action performed after using and objectively evaluating the present learning material. Data on angles of forward leaning were compared among these settings and analyzed by performing the Wilcoxon signed rank test using SPSS version 16.0 for Windows. The effectiveness of the present learning material was verified based on changes in the angle of forward leaning. In addition, an awareness survey was conducted before and after application of the present learning material. Survey contents were awareness of body mechanics as well as application of the present learning material (five-point scale). Results The mean angle of forward leaning was the largest for Setting 1 at 55.6 14.7 , which was at a dangerous level resulting in burden on the lower back. The mean angle for Setting 2 was 43.2 11.5 , which was significantly smaller than for Setting 1 but still at a dangerous level resulting in burden on the lower back. The mean angle of forward leaning for Setting 3 was 28.0 11.3 , indicating a significant improvement. Furthermore, the mean score for "wish to use body mechanics in the future" increased significantly (p<0.01) from 4.5 0.7 to 4.8 0.4 points following application of the present learning material. Conclusion Appｌication and evaluation by nurses of a body mechanics ｌearning material showed an increase in the awareness of body mechanics as well as improvement of posture during nursing actions. We will conduct further research in the future in order to verify the effectiveness of the present learning material and its effects on prevention of lower back pain in nurses.