New Perspectives on ACL Injury

ACL 损伤的新视角

• 批准号: 9889886
• 负责人: JAMES Anthony ASHTON-MILLER
• 金额: $ 29.68万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-05-11 至 2022-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9889886
• 关键词: 3-Dimensional; Adult; Age; Anterior; Anterior Cruciate Ligament; Area; Arthritis; Articular Range of Motion; Athletic; Cadaver; Data; Distal; Event; Exhibits; Experimental Designs; Experimental Models; Failure; Fatigue; Female; Femur; Funding; Hip region structure; Histology; Human; Image; Impulsivity; In Vitro; Individual; Injury; Knee; Knee Injuries; Lateral; Life; Ligaments; Measures; Microanatomy; Modeling; Muscle; Operative Surgical Procedures; Orthopedics; Paper; Patients; Pattern; Positioning Attribute; Prevention program; Research; Rest; Risk; Risk Factors; Rotation; Specimen; Survival Analysis; System; Tendon structure; Testing; Time; Torque; Training; Translations; Work; aged; anterior cruciate ligament injury; anterior cruciate ligament reconstruction; anterior cruciate ligament rupture; bone; clinical care; early onset; expectation; healing; high risk; histological image; improved; in vivo; male; reconstruction; sex; young adult

Abstract This proposal challenges the current dogma that `non-contact' anterior cruciate ligament (ACL) ruptures are due to sudden awkward landing or overload event. In the past funding cycle we developed the first evidence that the ACL can also fail under repetitive sub-maximal loading (Lipps 2013), helping to explain why an ACL can fail during a routine athletic maneuver. Pilot data suggest that this fatigue failure is associated with an accumulation of microdamage near the proximal femoral enthesis. We request funds to test this hypothesis. In AIM 1 60 pairs of knees from sex- and size-matched younger cadavers (30 males, 30 females) will be positioned at an initial flexion angle of 15o via pretensioned knee muscle-tendon equivalents that allow the knee to flex under a distal impulsive test load. ACL fatigue life will be determined via repetitive sub-maximal four-times bodyweight impulsive 3-D compound loading (compression + trans knee muscle loading + flexion moment + knee abduction moment + internal tibial axial torque) applied to each knee. A Cox regression model will be used to rank the relative importance of sex, internal femoral axial rotation range of motion (ROM) and lateral tibial slope in limiting ACL fatigue life. In AIM 2a we will use histological images and a binomial exact test to determine the percentage of the knees undergoing AIM 1 fatigue testing that exhibit microdamage at or near the femoral enthesis exceeding the +3*SD area found in the 32 untested, paired, control knees. Similarly, in AIM 2b we will salvage ACL femoral enthesis explants in 60 healthy young adults (30 females) aged 14-25 years undergoing routine reconstruction of their ACL and determine the percentage of explants exhibiting microdamage area exceeding the +3*SD value measured in 30 untested age- and sex-matched cadaveric controls. If greater-than-normal ACL microdamage is found in fatigue-tested knees in vitro (AIM 2a) and in ACL-injured patients in vivo (AIM 2b) this suggests the ACL can fail due to an accumulation of fatigue damage. This would imply that there may be time to modify athlete work-rest cycles to reduce ACL injury risk by arresting the injury cycle (Olsen 2006) and allowing the ACL to heal (Maekawa 1996).

抽象的 该提议挑战了当前的教条，即“非接触式”前交叉韧带（ACL）破裂是 由于突然尴尬的着陆或超负荷事件。在过去的资金周期中，我们开发了第一个证据 ACL在重复的亚最大负载下也可能失败（Lipps 2013），有助于解释为什么ACL 在常规运动中可能会失败。试验数据表明，这种疲劳失败与 在股骨近端埃及附近的微宏的积累。我们要求资金来检验这一假设。 在AIM 1 60双性别和大小匹配的年轻尸体（30名男性，30位女性）中的膝盖将是 通过屈曲的膝盖肌肉 - 刺刺等等效定位在15o的初始屈曲角度，允许 膝盖在远端冲动测试负荷下弯曲。 ACL疲劳寿命将通过重复的亚最大效果确定 四次体重冲动3-D复合载荷（压缩 +反式膝盖肌肉负荷 +屈曲 矩 +膝盖外展矩 +胫骨内部轴向扭矩）施加在每个膝盖上。 COX回归模型 将用于对性别，内部股骨轴向运动范围（ROM）和 在限制ACL疲劳寿命中，胫骨外侧斜率。 在AIM 2A中，我们将使用组织学图像和二项式精确测试来确定膝盖的百分比 经过AIM 1疲劳测试，在股骨度上或附近表现出微观障碍超过 +3*SD区域在32个未经测试的配对，对照膝盖中发现。同样，在AIM 2B中，我们将挽救ACL股骨 经过常规重建的60名健康年轻人（30名女性）的Enventes Epplants（30名女性） 它们的ACL并确定表现出超过 +3*SD的外植体的百分比 在30个未经测试的年龄和性别匹配的尸体对照中测量的价值。 如果在体外疲劳测试的膝盖中发现了大于正常的ACL微塑料（AIM 2A），并且在ACL受伤的膝盖中发现了 体内患者（AIM 2B）这表明由于疲劳损伤的积累，ACL可能失败。这会 暗示可能有时间修改运动员的工作待遇，以通过逮捕伤害来减少ACL伤害风险 循环（Olsen 2006），并允许ACL愈合（Maekawa 1996）。