Laxity and Malalignment in a Large Cohort Study of OA

描述(由申请人提供)：膝骨性关节炎是美国老年人慢性残疾的主要原因。由于对致病因素的了解有限，几乎没有预防膝骨性关节炎发展、进展或残疾的策略。人们越来越多地认识到膝关节松弛和对齐不良的作用，这两个潜在的可修改因素是当前应用的重点。这些因素正在西北大学正在进行的300个对象的MAK研究(膝关节炎中的机械因素)中进行研究，该研究已经获得了广泛的经验，并积累了它们重要性的证据。 作为最近资助的多中心骨性关节炎研究(MOST)的辅助研究，现在提出了一项关于膝关节骨性关节炎高危人群中松弛和对齐不良影响的综合研究。MOST是一项对3000名男性和女性进行的研究，主要目标是检查一组风险因素对三年内骨性关节炎结果的影响。MOST涉及4个地点：协调和核磁共振阅读中心(UCSF)、数据分析和X射线阅读中心(BU)和2个临床中心(UAB和UI)。 这一应用的假设集中在松弛和对齐失调是否各自与：与不松弛的膝盖和更中性的对齐的膝关节相比，发生骨性关节炎的风险更高；身体功能下降；骨性关节炎进展的风险。主要假说集中在症状和X光结果上；基于MRI的软骨形态评估也被建议作为一种手段，在最多队列的子集中检查这些因素中每一个因素的间隔室特异性影响。 要求提供支持：在大多数MAK研究中复制目前使用的测量系统和方案(用于松弛和对齐)；在MOST基线检查时评估松弛和对齐；在队列的一个子组中，在基线和3年随访时使用高场扫描仪获得MRI，以检查松弛和对齐不良导致的软骨体积和厚度的变化；以及测试松弛和对齐不良与重要骨关节炎结局风险的关系。

DESCRIPTION (provided by applicant): Knee OA is a leading cause of chronic disability in older Americans. Few strategies to prevent knee OA development, progression, or disability exist, due to limited knowledge of the responsible factors. There has been increasing recognition of the role of knee laxity and malalignment, two potentially modifiable factors that are the focus of the current application. These factors are being examined in the ongoing 300-subject MAK study (Mechanical Factors in Arthritis of the Knee) at Northwestern University, in which extensive experience has been gained with them, and evidence of their importance has accumulated. Now proposed is a comprehensive examination of the effect of laxity and malalignment in subjects with or at high risk to develop knee OA, as an ancillary study to the recently funded Multicenter OA Study (MOST). MOST is a study of 3000 men and women, with the primary goal of examining the effect of a panel of risk factors on OA outcomes over 3 years. MOST involves 4 sites: the Coordinating and MRI Reading Center (UCSF), Data Analysis and X-ray Reading Center (BU), and 2 Clinical Centers (UAB and UI). Hypotheses of this application focus on whether laxity and malalignment are each associated with: a higher risk of incident OA than non-lax knees and more neutrally aligned knees; a decline in physical function; risk of OA progression. Primary hypotheses focus on symptom and x-ray outcomes; MRI-based assessment of cartilage morphology is also proposed as a means of examining the compartment-specific effects of each of these factors in a subset of the MOST cohort. Support is requested: to replicate in MOST the measurement systems and protocols (for laxity and alignment) currently in use in the MAK study; to assess laxity and alignment at the baseline exam of MOST; in a subset of the cohort, to obtain MRI at baseline and at 3 year follow-up using a high-field scanner to examine change in cartilage volume and thickness as outcomes of laxity and malalignment; and to test the relationship of laxity and malalignment with risk of important OA outcomes.