Department of Orthopaedics and Traumatology, The University of Hong Kong, Pokfulam, Hong Kong.
Spine (Phila Pa 1976). 2010 Jul 15;35(16):1532-8. doi: 10.1097/BRS.0b013e3181ba021e.
A multiple-comparative study between normal and low back pain (LBP) patients before and after rehabilitation.
To examine whether there is a change in flexion-relaxation phenomenon in sitting in LBP patient following a rehabilitation treatment.
There is an association between LBP and seated spine posture. Previous study has reported an absence of flexion-relaxation phenomenon in LBP patients during sitting. However, it is unknown whether there is a difference in flexion-relaxation phenomenon in sitting in LBP patients before and after rehabilitation treatment.
A total of 20 normal subjects and 25 chronic LBP patients who underwent a 12 weeks rehabilitation program were recruited. Surface electromyography recordings during upright sitting and flexed sitting were taken from the paraspinal muscles (L3) bilaterally from the normal subjects, and in the LBP patients before and after the rehabilitation treatment. The main outcome measures for patients include the visual analogue scale, Oswestry disability index, subjective tolerance for sitting, standing and walking, trunk muscle endurance, lifting capacity, and range of trunk motion in the sagittal plane. Flexion-relaxation phenomenon in sitting, expressed as a ratio between the average surface electromyography activity during upright and flexed sitting, was compared between normal and patients; and in LBP patients before and after rehabilitation.
Flexion-relaxation ratio in sitting in normal subjects (Left: 6.83 +/- 3.79; Right: 3.45 +/- 2.2) presented a significantly higher (Left: P < 0.001; Right: P < 0.05) value than LBP patients (Left: 3.04 +/- 2.36; Right: 2.02 +/- 1.49). An increase in flexion-relaxation ratio in sitting was observed in LBP patients after rehabilitation (Left: 4.69 +/- 3.94, P < 0.05; Right: 3.58 +/- 2.97, P < 0.001), together with a significant improvement (P < 0.05) in subjective tolerance in sitting and standing, abdominal and back muscle endurance, lifting capacity, and range of motion. There were no significant changes in disability and pain scores, and subjective tolerance in walking.
Flexion-relaxation ratio in sitting has demonstrated its ability to discriminate LBP patients from normal subjects, and to identify changes in pattern of muscular activity during postural control after rehabilitation.
正常人和腰痛（LBP）患者康复前后的多项比较研究。
观察康复治疗后 LBP 患者坐姿中屈伸放松现象是否发生变化。
LBP 与坐姿下的脊柱姿势有关。先前的研究报告称，LBP 患者在坐姿时不存在屈伸放松现象。然而，尚不清楚 LBP 患者在康复治疗前后坐姿中屈伸放松现象是否存在差异。
共招募 20 名正常受试者和 25 名慢性 LBP 患者，他们接受了为期 12 周的康复计划。从正常受试者双侧 L3 棘突旁肌肉和 LBP 患者康复治疗前后，分别在直立坐姿和屈髋坐姿下进行表面肌电图记录。患者的主要观察指标包括视觉模拟评分、Oswestry 残疾指数、坐姿、站立和行走的主观耐受性、躯干肌肉耐力、提举能力以及矢状面躯干运动范围。比较正常人和患者、LBP 患者康复前后坐姿中屈伸放松现象（表示为直立和屈髋坐姿时平均表面肌电图活动的比值）。
正常受试者的坐姿屈伸比（左侧：6.83±3.79；右侧：3.45±2.2）明显高于 LBP 患者（左侧：P<0.001；右侧：P<0.05）（左侧：3.04±2.36；右侧：2.02±1.49）。LBP 患者康复后坐姿屈伸比增加（左侧：4.69±3.94，P<0.05；右侧：3.58±2.97，P<0.001），同时坐姿和站立的主观耐受性、腹部和背部肌肉耐力、提举能力以及活动范围均显著改善（P<0.05）。残疾和疼痛评分以及行走的主观耐受性无显著变化。
坐姿屈伸比能够区分正常人和 LBP 患者，并能识别康复后姿势控制中肌肉活动模式的变化。
