In vivo ACL Reconstruction Biomechanics

描述（由申请人提供）：尽管有大量关于ACL重建成功结果的报道，但超过40%的ACL重建患者存在异常松弛并进行翻修手术。此外，与更保守的治疗相比，ACL重建并不能降低骨关节炎的发生率。很少有定量数据表明ACL缺陷如何改变六自由度（6DOF）的体内膝关节运动学，以及当代ACL重建如何在体内生理负荷条件下恢复改变的6DOF膝关节运动学。此外，没有数据报道联合半月板损伤将如何影响ACL重建膝关节的体内功能。该项目的第一个目的是使用一种新的成像技术比较同一受试者健康和急性acl损伤膝盖的体内生物力学。人类受试者的三维（3D）膝关节模型将由MR图像创建。然后将这些模型与一系列双透视图像组相匹配，以准确再现膝关节在楼梯上升/下降、步态和负重屈伸等活动中的运动学。联合半月板损伤对acl损伤膝关节的影响也将直接从三维膝关节模型中确定。本课题的第二个目的是对ACL重建术后患者进行长期随访研究。为了量化前交叉韧带重建和合并半月板损伤对前交叉韧带重建疗效的生物力学影响，同样的患者将在前交叉韧带重建后的3年时间内，分别在6个月和36个月进行两次复诊，以进行额外的透视成像。acl重建患者将分为三组，无半月板损伤组、内侧半月板撕裂组和外侧半月板撕裂组。ACL重建的膝关节将在第一个目标中进行相同的体内功能活动时再次进行测试，并测量膝关节的6DOF运动学。定量分析联合半月板撕裂对前交叉韧带重建后膝关节运动学的影响。提出的研究是一种独特的方法来解决运动医学外科最重要的临床问题之一。我们简单而强大的分析技术将提供全面了解前交叉韧带和半月板联合损伤对6DOF动态膝关节功能的影响。长期随访数据将进一步阐明当代前交叉韧带重建在恢复正常膝关节功能方面的效果。这一知识将改善患者护理，作为指导方针，可以开发新的ACL重建技术，更准确地再现正常的体内膝关节运动学。为了恢复膝关节的正常生理功能，从而防止长期的关节退行性变，可以减少频繁的医院就诊、过度的物理治疗和翻修手术的需要——所有这些都是当前实践所固有的。公共卫生相关性。本研究将在纵向实验设计中测量前交叉韧带（ACL）重建前后患者的六个自由度膝关节运动学。我们还将分析联合半月板损伤对ACL重建效果的影响。从本研究中获得的知识将为开发新的ACL损伤手术治疗方法提供一个通用的、定量的生物力学指导，从而恢复关节的长期稳定性，防止受伤的ACL手术重建后的关节退变。

DESCRIPTION (provided by applicant): Despite the numerous reports on the successful results of ACL reconstruction, upwards of 40% of ACL reconstruction patients have abnormal laxity and undergo revision surgery. Moreover, ACL reconstruction does not reduce the rate of osteoarthritis when compared to more conservative treatments. There is little quantitative data demonstrating how ACL deficiency alters in-vivo knee kinematics in six degrees-of-freedom (6DOF) and how the contemporary ACL reconstruction restores the altered knee kinematics in 6DOF under in-vivo physiological loading conditions. Further, no data has been reported on how the combined meniscal injury will affect the in-vivo function of the ACL reconstructed knees. The first aim of this project is to compare the in-vivo biomechanics of healthy and acute ACL-injured knees within the same subject using a novel imaging technique. Three-dimensional (3D) knee models of human subjects will be created from MR images. These models will then be matched to a series of dual fluoroscopic image sets to accurately reproduce the kinematics of the knee during activities such as stair ascent/descent, gait and weight-bearing flexion-extension. The effects of combined meniscal damage to the ACL-injured knee will be determined directly from the three-dimensional knee models as well. The second aim of this project is to investigate the patients after ACL reconstruction surgery in a long-term follow-up study. To quantify the biomechanical effects of ACL reconstruction and a combined meniscal injury towards the efficacy of ACL reconstruction, the same patients from the first aim will return two times over a three year period, at 6 and 36 months following ACL reconstruction, for additional fluoroscopic imaging. ACL-reconstructed patients will be divided into three groups, those with no meniscal injury, those with medial meniscal tears, and those with lateral meniscal tears. The ACL- reconstructed knees will be tested again during the same in-vivo functional activities performed in the first aim, and 6DOF knee kinematics will be measured. The effect of combined meniscal tear on knee joint kinematics after ACL reconstruction will be analyzed quantitatively. The proposed study is a unique approach to one of the most important clinical problems in Sports Medicine Surgery. Our easy and powerful analysis technique will provide a thorough understanding of the effects of the combined ACL and meniscal injury on the 6DOF in-vivo dynamic knee joint function. The long-term follow up data will further elucidate the efficacy of contemporary ACL reconstruction in restoring normal knee function. This knowledge will lead to an improved patient care, as a guideline can be developed for new ACL reconstruction techniques that more accurately reproduce the normal in-vivo knee kinematics. In restoring the normal physiological functions of the knee joint and thereby preventing long-term joint degeneration, the need for frequent hospital visits, excessive physical therapy, and revision surgery - all inherent to the current practice - could be reduced. PUBLIC HEALTH RELEVANCE. This investigation will measure the six degrees-of-freedom knee kinematics of patients before and after anterior cruciate ligament (ACL) reconstruction in a longitudinal experimental design. The effects of combined meniscal injury on the efficacy of ACL reconstruction will also be analyzed. The knowledge gained from this study will provide a general, quantitative biomechanical guideline for developing new surgical treatments of ACL injuries, thereby restoring long term joint stability and preventing joint degeneration after surgical reconstruction of the injured ACL.