THE EFFECTS OF ORAL ESTROGEN AND PROGESTERONE ON THE ACL AND AT

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 前十字韧带(ACL)撕裂是女运动员的主要健康风险。与未受伤的女性相比，有前交叉韧带撕裂的女性更有可能发生膝关节早期退行性关节炎。前交叉韧带撕裂通常会在受伤后6-12个月内导致残疾。全美大学生体育协会伤害监测调查数据显示，女大学生运动员前交叉韧带撕裂率是男运动员的3-8倍。前交叉韧带撕裂会导致女性立即和迟发性的残疾。 对预防前交叉韧带撕裂的可改变的危险因素知之甚少。发现这些因素已被国家关节炎、肌肉骨骼和皮肤病研究所(NIAMS)和妇女健康研究办公室确定为主要目标。有许多被提出的危险因素，例如，前交叉韧带撕裂和月经周期之间的联系。在月经周期中，前交叉韧带的测量会发生变化。雌激素水平的波动被认为是前交叉韧带特性变化的原因。肌腱复合体，包括跟腱(AT)，为膝关节提供额外的稳定性。这些次级约束对膝关节的稳定性起着重要的作用。雌激素和黄体酮影响肌腱和韧带(如前交叉韧带和前交叉韧带)的胶原含量。一些研究人员建议服用口服避孕药，防止雌激素激增，以防止受伤。这些建议为时过早，因为ACL危险因素还没有得到彻底的研究，而且目前关于口服避孕药的任何建议都是通过小样本的回顾性研究得出的。 此外，需要进行前瞻性的、动力充足的研究，以确定补充激素，如口服避孕药(OCP)对前交叉韧带拉伸和张力特性的影响。以前的研究没有量化女性服用口服避孕药后，前交叉韧带松弛测量在整个月经周期中的变化。 这项拟议研究项目的具体目标是首先确定单相OCP对月经周期内前交叉韧带测量的影响。这项拟议研究项目的第二个目标是确定单相OCP对跨月经周期肌腱延伸性的影响。最后，拟议的项目将被用作交叉研究的初步数据，该研究将调查NIAMS应用R03或RO1时有无OCP的前交叉韧带测量结果的变化，该研究将对前交叉韧带撕裂的风险因素进行更全面的评估。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Anterior cruciate ligament (ACL) tears are a major health risk for female athletes. Early degenerative arthritis of the knee is more likely to develop in women with ACL tears as compared to their uninjured counterparts. ACL tears normally produce 6 - 12 months of disability after the injury. The National Collegiate Athletic Association Injury Surveillance Survey data identifies that female college athletes have a 3 - 8 times higher rate of ACL tears compared to males. ACL tears produce immediate and delayed disability in women. Little is known about modifiable risk factors in the prevention of ACL tears. Discovering these factors has been identified as a major goal by the National Institute of Arthritis Musculoskeletal and Skin Diseases (NIAMS) and the Office of Research on Women's Health. There are a number of proposed risk factors for instance a proposed association between ACL tears and the menstrual cycle. Over the menstrual cycle, changes are seen in the ACL measurements. The fluctuation of estrogen levels are proposed to be the cause of the changes in the ACL properties. Muscle-tendons complexes, including the Achilles tendon (AT), provide additional stability to the knee joint. These secondary restraints play an important role in the stability of the knee. Estrogen and progesterone affect the collagen content of tendons and ligaments (like the ACL and AT). Some investigators have recommended oral contraceptives, which prevents the estrogen spike, in order to prevent injury. These recommendations are premature since ACL risk factors have not been thoroughly studied and any current recommendations for the use of oral contraceptives are from retrospective studies with small sample sizes. Further, prospective, adequately powered, studies are needed to define the affects of supplemental hormones such as oral contraceptives (OCP) on the stretch and strain properties of the ACL. Previous studies quantifying the change in ACL laxity measurements across the menstrual cycle while a woman is on OCPs do not exist. The specific aims of the proposed research project are first, to identify the affects of a monophasic OCPs on ACL measurements across the menstrual cycle. The secondary aim of the proposed research project is to identify the affects of monophasic OCPs on tendon extensibility across the menstrual cycle. Lastly, the proposed project will be used as preliminary data for a cross-over study investigating the change in ACL measurements with and without OCPs in an RO3 or RO1 application to NIAMS, which will carry out a more comprehensive evaluation on the risk factors for ACL tears.