论文部分内容阅读
目的 观察30 d-6°头低位卧床实验后志愿者腰椎高度、腰椎间隙中矢状位面积、腰椎前凸角度以及椎旁肌肉横切面积的变化.方法 14名健康男性参加30 d卧床模拟失重实验.于卧床前1天、卧床第30天分别进行腰椎核磁检测,同时测量人体腰椎高度、腰椎间隙中矢状位面积、腰椎前凸角度以及椎旁肌肉横切面积.结果 30 d卧床实验后志愿者腰椎高度增加(P<0.01)、腰椎间隙中矢状位面积增大(P<0.01),椎旁肌肉横切面积减少(P<0.01),而腰椎前凸角度变化不明显.结论 30 d-6°头低位卧床模拟失重对人体腰椎稳定性和功能有影响,从而导致人体腰椎的生物力学变化.“,”Objective To study the changes of entire lumbar spinal height,the lordotic angle,the midsagittal area between adjacent lumbar vertebral bodies and the cross-sectional area of lumbar paraspinal muscles following 30 d-6°head-down bed rest (HDBR.Methods A 30 d-6°HDBR experiment was proposed to simulate weightlessness effects.Fourteen healthy male subjects volunteered to participate in the experiment.All subjects underwent magnetic resonance imaging (MRI)test in supine psoas-relaxed position before and after HDBR.Midsagittal views were used to measure the entire lumbar spinal height,the midsagittal area between adjacent lumbar vertebral bodies and lordotic angle.Axial MR image at the level of the L4-L5 disc was used to determine cross-sectional area of lumbar paraspinal muscles.Results After 30 d-6°HDBR,the entire lumbar spinal height of subjects was higher and the midsagittal areas of subjects were larger than those measured before HDBR (P < 0.01).The cross-sectional area of lumbar paraspinal muscles reduced significantly (P < 0.01).The lordotic angle of subjects did not change significantly.Conclusion Thirty days of HDBR at-6°can affect lumbar spinal stability and function and then result in the changes in lumbar spinal biomechanics.