Biomechanical Adaptations to Strength Training OA

描述（由申请人提供）：膝关节骨关节炎（OA）的治疗性运动方案在OA的保守治疗中起着重要作用。增强股四头肌和腘绳肌是这些锻炼计划的主要目标之一，然而增强如何影响骨关节炎膝关节的机制尚不清楚。据推测，加强膝关节肌肉对OA等膝关节问题的积极影响是由于增强的肌肉具有“稳定”或“减轻压力”或以某种方式“保护”膝关节的能力。这种普遍持有的信念尚未经过实验评估。本研究的目的是阐明加强膝关节初级肌肉组织如何导致直接影响膝关节机械负荷的生物力学适应的机制。具体目的是确定OA患者和年龄匹配的非OA患者水平行走和爬楼梯时的膝关节生物力学力和力矩，对两组进行股四头肌和腘绳肌的力量训练，然后比较两组训练前后的膝关节接触力和力矩。PIs假设，对于有足够力量进行行走和爬楼梯的患者，股四头肌和腘绳肌的力量对膝关节力学的影响很小。他们认为，只有肌肉组织明显较弱的患者才会因力量训练而出现关节生物力学变化，而力量的增加并不一定能“保护”关节。两组（OA患者和年龄匹配的对照组）将接受为期2个月的力量训练计划。将收集训练前后的人口学、社会心理和生物力学指标。在水平行走和爬楼梯时将使用三维步态分析。肌电图将用于确定肌肉的激活情况。肌肉力量和关节动力学将估计使用SIMM肌肉骨骼建模软件和逆动力学。将使用重复测量方差分析和方差分析来检验研究假设。本研究的结果将支持国家目标，通过提供有关治疗干预是否以及如何直接影响与膝关节OA相关的机械功能障碍的答案，促进基于证据的关节炎干预。

DESCRIPTION (Provided by Applicant): Therapeutic exercise programs for osteoarthdtis (OA) of the knee play a major role in conservative management of OA. Strengthening of the quadriceps and hamstrings is one of the primary objectives of these exercise programs, yet the mechanisms of how strengthening affects the Osteoarthritic knee are not well understood. It is speculated that the positive influence of strengthening the knee musculature for OA and other knee joint problems is due to the strengthened muscle's ability to "stabilize" or "reduce stress" or somehow "protect" the knee joint. This commonly held belief has not been assessed experimentally. The purpose of this study is to elucidate the mechanisms of how strengthening primary knee joint musculature may cause biomechanical adaptations that directly influence knee joint mechanical loading. The specific aims will be to determine knee joint biomechanical forces and moments during level walking and stair climbing in patients with OA and age matched persons without OA, to strength train quadriceps and hamstrings musculature for both groups, and then to compare knee joint contact forces and moments before and after training in both groups. The PIs hypothesize that strength of the quadriceps and hamstrings has little influence on knee joint mechanics in patients that have strength sufficient for the functional tasks of walking and stair climbing. They believe that only patients with significantly weaker musculature compared to age-matched controls will show joint biomechanical changes due to strength training and that increased strength does not necessarily "protect" the joint. Two groups (OA patients and age-matched controls) will undergo a 2-month supervised strength-training program. Demographic, psychosocial, and biomechanical measures will be collected pre and post training. Three-dimensional gait analysis will be used during level walking and stair climbing. EMG will be used to determine muscle activation. Muscle forces and joint kinetics will be estimated using SIMM musculoskeletal modeling software and inverse dynamics. Repeated measures ANOVA and ANCOVA will be used to test the study hypotheses. The results of this study will support national objectives to promote evidence based arthritis interventions by providing answers pertaining to whether and how a therapeutic intervention directly affects the mechanical dysfunction associated with OA of the knee.