Evaluation of risk factors for cervical spine disorders due to manual material handling tasks
Work-related musculoskeletal disorders (MSD) of the neck or cervical spine result in longer sick leaves, substantial levels of human suffering, and high costs for society. Epidemiological studies clearly indicate a strong association between MSD of the cervical spine and manual material handling (MMH) activities involving forceful arm exertions and heavy lifting tasks. However, studies evaluating cervical spine MSD due to MMH tasks are rather limited. In this study a variety of isometric lifting tasks were studied to understand the contribution of the neck muscles during MMH activities. Eighteen healthy participants (age 23.5 ±3.5, weight 76.2 ±16.2 kg, height 170.3 ±10.8 cm) performed isometric lifting tasks at combinations of three heights (elbow, shoulder, and overhead), three levels of lifting weight (25％, 50％, and 75％ of maximum static strength), and three neck postures (neutral, flexed, and extended). The activities of the major neck muscles, the sternocleidomastoid and the upper trapezius, were evaluated using electromyography (EMG) and expressed in terms of a normalized MAV (mean absolute value). The activities of the neck muscles increased significantly with increased lifting height and weight. The trapezius muscle was most active at the flexed neck posture while the sternocleidomastoid muscle was most active at the extended neck posture. The results of this study demonstrate that the neck muscles play an active role during lifting activities.
Ashish D. Nimbarte Fereydoun Aghazadeh Laura H. Ikuma
Department of Construction Management & Industrial EngineeringLouisiana State University, Baton Roug Department of Construction Management & Industrial Engineering Louisiana State University, Baton Rou
国际会议
17th World Congress on Ergonomics(第十七届国际人类工效学大会)
北京
英文
1-6
2009-08-09（万方平台首次上网日期，不代表论文的发表时间）