Crenshaw Jeremy R, Bernhardt Kathie A, Atkinson Elizabeth J, Khosla Sundeep, Kaufman Kenton R, Amin Shreyasee
Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, USA; Department of Kinesiology and Applied Physiology, University of Delaware, Newark, DE, USA.
Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, USA.
Gait Posture. 2018 Sep;65:74-80. doi: 10.1016/j.gaitpost.2018.06.117. Epub 2018 Jun 19.
Compensatory stepping thresholds evaluate the response to postural disturbances. Although such fall-recovery measures are a promising indicator of fall risk, the relationships between stepping thresholds and other measures used to predict falls are not well established.
We sought to quantify the relationships between stepping thresholds and other measurements used to assess fall risk in older women, a population at high risk for falls and related injuries, including fractures.
We studied 112 ambulatory, community-dwelling women, age 65 years or older. Using a treadmill to deliver standing postural disturbances, we determined anterior and posterior single-stepping and multiple-stepping thresholds. These thresholds represented the magnitude of the disturbance that elicited one step or more than one step, respectively. We also assessed balance confidence, functional reach, unipedal stance time, isometric strength, obstacle crossing, postural sway, and gait kinematics. Outcomes were normalized to body size.
After accounting for age, stepping thresholds were, at most, moderately correlated (Pearson partial correlation coefficients r = 0.20 to 0.40 and r = -0.21 to -0.31) to several assessments of gait, postural control, and strength. Approximately 24-52% of the variance in stepping thresholds was explained by a combination of age and other fall risk assessments, which frequently consisted of balance confidence, unipedal stance time, obstacle crossing, the Romberg ratio of postural sway, and/or strength.
Our results suggest that anteroposterior fall-recovery ability, as assessed by stepping thresholds, can only be partially inferred from age and a combination of assessments of sway, strength, unipedal tasks, and balance confidence. Compensatory stepping thresholds may provide information on stability maintenance unique from other assessments of fall risk. Further investigation would be necessary to determine whether stepping thresholds are better predictors of falls in older women.
代偿性步幅阈值用于评估对姿势干扰的反应。尽管此类跌倒恢复指标是跌倒风险的一个有前景的指标，但步幅阈值与其他用于预测跌倒的指标之间的关系尚未完全明确。
我们试图量化步幅阈值与其他用于评估老年女性跌倒风险的测量指标之间的关系，老年女性是跌倒及相关损伤（包括骨折）的高风险人群。
我们研究了112名年龄在65岁及以上、居住在社区且能自主行走的女性。使用跑步机施加站立姿势干扰，我们确定了前后方向的单步和多步阈值。这些阈值分别代表引发一步或多步的干扰幅度。我们还评估了平衡信心、功能性伸展、单腿站立时间、等长肌力、跨越障碍物能力、姿势摆动和步态运动学。结果根据身体尺寸进行了标准化。
在考虑年龄因素后，步幅阈值与步态、姿势控制和力量的多项评估指标最多呈中度相关（皮尔逊偏相关系数r = 0.20至0.40以及r = -0.21至-0.31）。步幅阈值约24 - 52%的变异可由年龄和其他跌倒风险评估指标共同解释，这些指标通常包括平衡信心、单腿站立时间、跨越障碍物能力、姿势摆动的罗姆伯格比率和/或力量。
我们的结果表明，通过步幅阈值评估的前后方向跌倒恢复能力，只能部分地从年龄以及摆动、力量、单腿任务和平衡信心的综合评估中推断出来。代偿性步幅阈值可能提供与其他跌倒风险评估不同的关于稳定性维持的信息。有必要进一步研究以确定步幅阈值是否是老年女性跌倒的更好预测指标。
