Messier Stephen P, Glasser Julie L, Ettinger Walter H, Craven Timothy E, Miller Michael E
J. B. Snow Biomechanics Laboratory, Department of Health & Exercise Science, Wake Forest University, Winston-Salem, North Carolina 27109, USA.
Arthritis Rheum. 2002 Apr 15;47(2):141-8. doi: 10.1002/art.10339.
To document changes in lower extremity strength and balance over a 30-month period in older adults with chronic knee pain, and to identify relationships among these variables that may prove useful in designing a subsequent clinical intervention trial.
This longitudinal, 30-month, observational study was designed to examine the association of physical, psychological, social, and environmental factors with severity and progression of physical disability caused by chronic knee pain. This article will focus on 2 physical measures: strength and dynamic balance. The participants were a cohort of 480 adults 65 years of age or older with chronic knee pain. Measurements included: 1) force platform dynamic balance measure of the center of pressure excursion during a forward and subsequent backward lean, 2) isokinetic strength measures of concentric and eccentric knee flexion and extension, and concentric ankle plantar flexion and dorsiflexion, and 3) body mass index and a knee pain scale to measure obesity and knee pain, respectively.
A maximum-likelihood analysis revealed an overall significant decline in knee (P < 0.001) and ankle (P = 0.012) strength, and balance (P < 0.001) after a 30-month followup period. Participants with greater knee strength at baseline had less expected decline in balance at followup than their weaker counterparts (4.2% versus 7.7% for the 75th versus 25th percentiles of strength; P = 0.023). However, the absolute decline in balance over 30 months was similar regardless of baseline ankle strength.
Adults age >or=65 years with chronic knee pain experience significant declines in balance and lower extremity strength over a 30-month period. Moreover, greater knee and ankle muscular strength is associated with better balance. Previous studies have shown that weight training is effective in improving balance in older adults with knee osteoarthritis. Taken together, these studies present a strong rationale for incorporating weight training into an exercise prescription for older adults with chronic knee pain.
记录慢性膝关节疼痛的老年人在30个月期间下肢力量和平衡能力的变化，并确定这些变量之间的关系，这可能有助于设计后续的临床干预试验。
这项为期30个月的纵向观察性研究旨在检查身体、心理、社会和环境因素与慢性膝关节疼痛导致的身体残疾严重程度和进展之间的关联。本文将重点关注两项身体指标：力量和动态平衡。参与者为480名65岁及以上患有慢性膝关节疼痛的成年人。测量内容包括：1）在向前和随后向后倾斜过程中压力中心偏移的测力平台动态平衡测量；2）膝关节屈伸、踝关节跖屈和背屈的等速力量测量；3）分别用于测量肥胖和膝关节疼痛的体重指数和膝关节疼痛量表。
最大似然分析显示，在30个月的随访期后，膝关节（P < 0.001）和踝关节（P = 0.012）力量以及平衡能力（P < 0.001）总体上显著下降。基线时膝关节力量较强的参与者在随访时平衡能力的下降幅度低于力量较弱的参与者（力量第75百分位数与第25百分位数相比，分别为4.2%对7.7%；P = 0.023）。然而，无论基线踝关节力量如何，30个月内平衡能力的绝对下降幅度相似。
65岁及以上患有慢性膝关节疼痛的成年人在30个月期间平衡能力和下肢力量显著下降。此外，更强的膝关节和踝关节肌肉力量与更好的平衡能力相关。先前的研究表明，力量训练对改善膝关节骨关节炎老年人的平衡能力有效。综合来看，这些研究为将力量训练纳入慢性膝关节疼痛老年人的运动处方提供了有力的理论依据。
