Reducing Low-back Disorders Using a New Sitting Design

使用新的坐姿设计减少腰部疾病

• 批准号: 6553472
• 负责人: MOHSEN MAKHSOUS
• 金额: $ 7.25万
• 依托单位: REHABILITATION INSTITUTE OF CHICAGO D/B/A SHIRLEY RYAN ABILITYLAB
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-30 至 2004-09-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6553472
• 关键词: backache; clinical research; ergonomics; human subject; human therapy evaluation; occupational health /safety; patient oriented research; physical therapy; posture

DESCRIPTION: Work-related low back musculoskeletal disorders are common and affect a large portion of the workforce. Occupational risk factors for LBP include sustained static muscle load, and inappropriate curvature/position of the spine and pelvis. Sitting may cause backward rotation of the pelvis, reduction in lumbar lordosis, changes in muscle activities and disc pressure, excessive pressure over the ischium and coccyx, and certainly the associated LBP. A new seat design, of which the back part of seat (BPS) can be dynamically tilted downward and upward with respect to the front part of the seat (FPS) providing adjustment of thigh and ischial support and the back support is adjustable in height and volume, will be investigated. It was found in the pilot study that sitting with lowered BPS and adjustment of low back support resulted in more evenly distributed contact pressure, reduced peak pressure under the ischia, increased total and segmental lumbar lordosis, forwardly rotated the pelvis, and increased lumbar intervertebral heights. We believe that the functional relations of the seat and backrest need to be further investigated in order to not only prevent flattening of the lumbar spine but also reduce the ischial load in long term sitting, which are related to LBP. We propose to study the biomechanical and neuromuscular effects of the new sitting concept, and evaluate quantitatively the benefits in the LBP patients for using appropriate lumbar support that increases lordosis and decreases the sitting pressure and load carried by the ischial tuberosities. Hypothesis 1: When the BPS is tilted downward, load on the ischial tubercles and lumbar spine will be reduced and shifted to the thighs and the thoracic spine, respectively. Low back muscle activities will also be reduced. Specific aim 1: Contact pressure distributions between the buttock-thighs and seat, and between the back and backrest, load carried at the seat and back will be evaluated with and without ischial support, combined with flat or adjusted back support. The muscular activities involved in stabilizing the trunk under these conditions will be investigated. Hypothesis 2: Increase in lumbar lordosis, forward rotation of the pelvis, and larger intervertebral heights will be observed when the BPS is tilted down to reduce ischial support. Specific aim 2: The total and segmental lumbar lordosis, pelvis inclination, and intervertebral spaces of lumbar spine, will be measured using X-ray images and compared under the different sitting conditions. Hypothesis 3: Sitting alternately between the postures with the BPS at level and tilted down positions will reduce the discomfort/pain associated with sitting. As a result, patients with LBP will better tolerate prolonged sitting. Specific aim 3: The subjective evaluation and impressions gained from the use of such a sitting design for a period of four months will be evaluated using questionnaire in two groups of chronic LBP patients with pain history and symptoms.

描述：与工作相关的腰部肌肉骨骼疾病很常见，影响很大一部分劳动力。腰痛的职业危险因素包括持续的静态肌肉负荷以及脊柱和骨盆的不适当的弯曲/位置。坐着可能会导致骨盆向后旋转、腰椎前凸减少、肌肉活动和椎间盘压力变化、坐骨和尾骨压力过大，当然还有相关的腰痛。将研究一种新的座椅设计，其中座椅后部（BPS）可相对于座椅前部（FPS）动态向下和向上倾斜，提供大腿和坐骨支撑的调节，并且背部支撑的高度和体积可调节。初步研究发现，降低 BPS 的坐姿和调整腰部支撑可以使接触压力分布更均匀，坐骨下峰值压力降低，腰椎整体和节段前凸增加，骨盆前旋，腰椎间高度增加。我们认为，需要进一步研究座椅和靠背的功能关系，不仅可以防止腰椎扁平化，还可以减轻与腰痛相关的长期坐坐骨负荷。我们建议研究新坐姿概念的生物力学和神经肌肉效应，并定量评估 LBP 患者使用适当的腰部支撑来增加脊柱前凸并减少坐骨结节所承受的坐压和负荷的益处。 假设1：当BPS向下倾斜时，坐骨结节和腰椎的负荷会减少，并分别转移到大腿和胸椎。腰部肌肉的活动也会减少。 具体目标 1：在有或没有坐骨支撑的情况下，结合平坦或可调节的靠背支撑，评估臀部大腿和座椅之间以及靠背和靠背之间的接触压力分布、座椅和靠背承受的负载。将研究在这些条件下稳定躯干所涉及的肌肉活动。 假设2：当BPS向下倾斜以减少坐骨支撑时，会观察到腰椎前凸增加、骨盆前旋和椎间高度增大。具体目标2：利用X线图像测量腰椎整体和节段前凸、骨盆倾斜度和腰椎椎间隙，并在不同坐姿下进行比较。 假设 3：在 BPS 处于水平位置和向下倾斜位置之间交替坐会减少与坐相关的不适/疼痛。因此，腰痛患者能够更好地忍受长时间坐着。具体目标3：将通过问卷调查对两组有疼痛史和症状的慢性腰痛患者进行为期四个月的使用这种坐姿设计所获得的主观评价和印象。