Department of Physical Therapy and Rehabilitation Science, University of California, 1500 Owens St., Suite 400, San Francisco, CA 94158, USA.
J Gerontol A Biol Sci Med Sci. 2013 Aug;68(8):976-83. doi: 10.1093/gerona/glt009. Epub 2013 Apr 30.
Maintaining physical function is an important prerequisite for preserving independence in later life. Greater degrees of kyphosis in the thoracic spine are prevalent in older persons and accompanied by reduced physical function in multiple cross-sectional studies. It is unknown whether kyphosis predicts worse physical function over time.
We retrospectively assessed whether greater magnitude of kyphosis is associated with decline in self-reported and objectively measured physical function over 15 years. Digitized Cobb angle kyphosis (T4-T12) was derived from supine lateral thoracic spine radiographs in a cohort of 1,196 women aged 65 and older (mean = 69.3 years [SD = 4.0]). Using regression models, we evaluated associations of baseline kyphosis with both self-reported functional status and objectively measured gait speed, grip strength, and timed chair stands cross-sectionally and as change assessed over 15 years.
In cross-sectional multivariate analyses, with each 10-degree increment of kyphosis, grip strength was 0.24 kg lower (p = .02), but there were no significant associations between kyphosis and functional status, gait speed, or timed chair stand, likely reflecting the high functioning study participants. In multivariate longitudinal analysis, with each 10-degree increment in baseline kyphosis, there was 0.07 point additional decline in functional status (p = .09), 0.01 m/s more decline in gait speed (p = .07), and 0.32 s greater decline in time to complete five chair stands (p = .004), but no association with decline in grip strength.
Greater magnitude of kyphosis may predict worsening lower extremity function over time in older women. Early recognition and preventative measures against kyphosis progression may help preserve physical function over the long term.
保持身体功能是晚年保持独立的重要前提。在多项横断面研究中，胸椎后凸程度较大在老年人中更为普遍，并伴有身体功能下降。目前尚不清楚后凸是否预示着随着时间的推移身体功能会恶化。
我们回顾性评估了在 15 年的时间里，更大程度的后凸是否与自我报告和客观测量的身体功能下降有关。在一个由 1196 名 65 岁及以上女性组成的队列中，从仰卧位侧位胸椎 X 光片上得出数字化 Cobb 角后凸（T4-T12）（平均年龄为 69.3 岁[SD=4.0]）。使用回归模型，我们评估了基线后凸与自我报告的功能状态和客观测量的步态速度、握力和定时椅子站立的横断面以及 15 年期间的变化之间的关联。
在横断面多变量分析中，后凸每增加 10 度，握力就会降低 0.24 公斤（p=0.02），但后凸与功能状态、步态速度或定时椅子站立之间没有显著关联，这可能反映了研究参与者的高功能状态。在多变量纵向分析中，基线后凸每增加 10 度，功能状态会额外下降 0.07 分（p=0.09），步态速度会下降 0.01 米/秒（p=0.07），完成五次椅子站立的时间会延长 0.32 秒（p=0.004），但握力没有下降。
更大程度的后凸可能预示着老年女性的下肢功能随着时间的推移而恶化。早期识别和预防后凸进展的措施可能有助于长期保持身体功能。
