Novel MRI Methods for Osteochondritis Dissecans (OCD) / Osteochondrosis (OC)

项目摘要/摘要 剥脱性骨软骨炎(OCD)/骨软骨病(OC)是儿童重要的骨科疾病； 然而，其病因和发病机制尚不清楚。强迫症/OC在以下地区非常普遍(几乎100%受到影响) 生长中的猪导致跛行。我们课题组以前的工作已经证明， 猪的强迫症/骨质疏松症涉及软骨管供血不足，导致骨骺(生长)坏死。 软骨。我们假设儿童OC/OCD的发病机制是相似的；然而， 剥脱性骨软骨炎(OCD)与软骨管血供障碍之间的关系 研究的原因是：1)缺乏非侵入性成像技术，无法在体内显示这些结构；2)有限 获得适当的尸检组织。我们已经发展了一种独特的合作方式， 磁共振成像(MRI)专家以及兽医和人类整形外科研究人员将利用 明尼苏达大学磁共振研究中心的特殊资源来填写 以上提到的知识差距。我们的团队最近开发并验证了MRI方法来识别 幼猪骨骺软骨的软骨管、血管和缺血性坏死。我们希望 将这些研究扩展到儿童和青少年，以调查关节的成熟过程- 人股骨远端无创的骨骺软骨，并与猪股骨远端骨骺软骨进行比较。这 将通过完成四个具体目标来实现。目标1和目标2侧重于发展/ 实施/验证新的磁共振成像技术，体外成像血管供应和软骨基质 正常儿童和幼猪身体标本的特征/形态 将出现骨软骨病的亚临床损害(允许对正常组织和区域进行评估 软骨坏死)。目标3和4侧重于快速儿科成像方案的开发和测试 用于正常儿童和首次诊断为强迫症的儿童的体内研究。这项研究将有多个 好处：1)证实猪是这种重要人类疾病的高度合适的动物模型，2) 提供了一种在疾病发展的早期诊断疾病的方法，当时正在进行治疗 可能是有效的，以及3)大大提高了我们对这种疾病的病理生理学的理解。

Project Summary/Abstract Osteochondritis Dissecans (OCD)/Osteochondrosis (OC) is an important orthopaedic disease in children; however, the etiology and pathogenesis remain unclear. OCD/OC is highly prevalent (nearly 100% affected) in growing pigs causing lameness. Previous work by our group has demonstrated that the pathogenesis of OCD/OC in pigs involves failure of cartilage canal blood supply, with resulting necrosis of epiphyseal (growth) cartilage. We hypothesize that the pathogenesis of OC/OCD in children is similar; however, the relationship between failed cartilage canal blood supply and osteochondritis dissecans (OCD) in people has not been studied due to 1) lack of noninvasive imaging techniques to visualize these structures in vivo and 2) limited access to appropriate post mortem tissues. We have developed a unique collaboration among magnetic resonance imaging (MRI) experts and veterinary and human orthopaedic researchers that will make use of the exceptional resources at the Center for Magnetic Resonance Research at the University of Minnesota to fill in the above mentioned gaps in knowledge. Our group recently developed and validated MRI methods to identify cartilage canal blood vessels and ischemic necrosis of the epiphyseal cartilage in young pigs. We wish to extend these studies to children and adolescents to investigate the maturation process of the articular- epiphyseal cartilage of the distal femur noninvasively in humans and compare it to that occurring in swine. This will be accomplished by the completion of four specific aims. Aims 1 and 2 focus on the development/ implementation/validation of novel MRI techniques, ex vivo, to image the vascular supply and cartilage matrix characteristics/morphology in cadaveric specimens from normal children and from young pigs in which subclinical lesions of osteochondrosis will be present (allowing evaluation of normal tissues as well as of areas of cartilage necrosis). Aims 3 and 4 focus on the development and testing of a rapid pediatric imaging protocol for in vivo studies in normal children and children first diagnosed with OCD. This research will have multiple benefits by 1) validating swine as a highly appropriate animal model of this important human disease, 2) providing a method to diagnose the disease at an early point in its development at which time treatments are likely to be effective, and 3) greatly improving our understanding of the pathophysiology of the disease.