Department of Physical Therapy and Rehabilitation Science, University of California San Francisco, 1500 Owens, Suite 400, San Francisco, CA 94143, USA.
J Gerontol A Biol Sci Med Sci. 2012 Feb;67(2):191-5. doi: 10.1093/gerona/glr160. Epub 2011 Aug 30.
Older adults with hyperkyphosis are at increased risk of falls, fractures, and functional decline. Modifiable risk factors for hyperkyphosis have not been well studied. Our objective was to determine whether spinal muscle area and density are associated with hyperkyphosis, independent of age, race, sex, bone mineral density, and trunk fat.
Using data from the Pittsburgh site of the Health, Aging, and Body Composition study, we performed a baseline cross-sectional analysis. Participants were black and white men and women 70-79 years old (N = 1172), independent in activities of daily living and able to walk ¼ mile and up 10 steps without resting. We measured Cobb's angle of kyphosis from supine lateral scout computed tomography scans, and categorized hyperkyphosis as Cobb's angle >40°. Axial images from lateral scout computed tomography scans assessed spinal extensor muscle cross-sectional area and density (proxy for fat infiltration).
In our sample, 21% had hyperkyphosis. Prevalence in black men was 11%; in white men, 17%; in black women, 26%; and in white women, 30%. In multivariate analysis, each standard deviation increase in muscle density was associated with a 29% reduction in the odds of hyperkyphosis, independent of covariates. Muscle area was not significantly associated with hyperkyphosis.
Lower spinal muscle density is associated with hyperkyphosis in healthy community-dwelling older adults. This potentially modifiable risk factor could be targeted in exercise interventions. Randomized trials are needed to determine whether an exercise program targeting spinal muscle density reduces hyperkyphosis and in turn improves health outcomes.
患有严重后凸畸形的老年人跌倒、骨折和功能下降的风险增加。严重后凸畸形的可改变危险因素尚未得到很好的研究。我们的目的是确定脊柱肌肉面积和密度是否与严重后凸畸形有关，而与年龄、种族、性别、骨密度和躯干脂肪无关。
利用匹兹堡健康、衰老和身体成分研究（Health, Aging, and Body Composition study）的资料，我们进行了基线横断面分析。参与者为 70-79 岁的黑人和白人男性和女性（N=1172），日常生活活动自理，能够行走¼英里和不休息地爬上 10 级台阶。我们从仰卧位侧位 CT 扫描测量后凸角，将 Cobb 角>40°归类为严重后凸畸形。侧位 CT 扫描的轴向图像评估脊柱伸肌横截面积和密度（脂肪浸润的替代指标）。
在我们的样本中，21%的人患有严重后凸畸形。黑人男性的患病率为 11%；白人男性为 17%；黑人女性为 26%；白人女性为 30%。在多变量分析中，肌肉密度每增加一个标准差，严重后凸畸形的几率就会降低 29%，与协变量无关。肌肉面积与严重后凸畸形无显著相关性。
在健康的社区居住的老年人群中，较低的脊柱肌肉密度与严重后凸畸形有关。这个潜在的可改变的危险因素可以在运动干预中针对。需要进行随机试验，以确定针对脊柱肌肉密度的锻炼方案是否能减少严重后凸畸形，进而改善健康结果。
