Adjacent Segment Mechanics in Cervical Arthrodesis Patients

 描述(申请人提供)：前路颈椎摘除融合术(ACDF)是美国最常见的治疗退行性颈椎疾病的外科手术。不幸的是，ACDF不能防止初次手术邻近运动节段的退变(即邻近节段疾病)，大约25%的患者需要在初次手术后10年内再次手术。本研究旨在找出可能增加邻近节段退变风险的因素。这项研究可能有助于通过减少再手术来减少医疗支出，并提高患者的安全和生活质量。摘要：颈椎融合术后邻近节段病变的病因仍存在较大争议。邻近节段疾病被认为是由以下一个或多个不同的原因引起的：1)邻近节段的自然病史；2)邻近节段的破坏 初始手术的解剖学；以及3)融合后邻近节段的生物力学应力。我们研究的长期目标是减少或预防脊柱有症状的相邻节段退变。这项研究的总体假设是，ACDF术后相邻节段的运动学(即平移、旋转、螺旋运动轴)和关节运动学(即椎间盘变形和小关节表面相互作用)主要由患者特定的解剖和医源性因素决定，而不是由融合引起的生物力学应力增加决定的。建议进行前瞻性纵向研究，以确定患者特有的因素(特异性目标1)、医源性因素(特异性目标2)和改变的生物力学(特异性目标3)对融合后动态颈椎功能的影响程度。研究对象为C56(n=22)和C67(n=22)单节段融合者，C456(n=22)和C567(n=22)两节段融合者，以及年龄与融合者年龄相近的无症状对照组(n=22)。患者将在手术前、手术后一年和手术后三年进行测试。在每次测试中， 参与者将完成临床问卷以评估疼痛和功能，他们将执行头部和颈椎的全范围运动屈曲、伸展和轴向旋转，而双平面X光片以每秒30张图像的速度记录。在每一次测试中，将利用高度准确和有效的基于体积模型的跟踪过程和定制数据分析软件来确定椎间运动学(即平移、旋转、Motin的螺旋轴)和关节运动学(即椎间盘变形和小关节表面相互作用)。这项前瞻性研究将确定对邻接影响最大的因素 颈椎融合术后节段力学。如果假说得到证实，这将为更多地关注患者特有的因素和手术技术提供支持。或者，如果结果表明关节融合术后增加的应力主要影响相邻节段的力学，这将为增加对运动设计的关注提供支持。 备用设备。

 DESCRIPTION (provided by applicant): Anterior cervical discectomy and fusion (ACDF) is the most common surgical procedure to treat degenerative cervical spine disease in the United States. Unfortunately, ACDF does not prevent degeneration of motion segments adjacent to the initial surgery (i.e. adjacent segment disease), and approximately 25% of the patients require reoperation within 10 years of the initial surgery. This study aims to identify factors that may increase the risk for adjacent segment degeneration. This research may help decrease healthcare spending by reducing reoperations and improve patient safety and quality of life. Abstract: The etiology of adjacent segment pathology following cervical fusion remains highly controversial. Adjacent segment disease is believed to result from one or more of the following distinct causes: 1) the natural history of the adjacent disc; 2) disruption of the adjacent segment anatomy due to the initial surgery; and 3) biomechanical stress on the adjacent level following the fusion. The long-term goal of our research is to reduce or prevent symptomatic adjacent segment degeneration in the spine. The overall hypothesis of this study is that adjacent segment kinematics (i.e. translations, rotations, helical axis of motion) and arthrokinematics (i.e disc deformation and facet joint surface interactions) after ACDF are determined primarily by patient-specific anatomy and iatrogenic factors, and not by increased biomechanical stress due to the fusion. A prospective longitudinal study is proposed to determine to what extent patient-specific factors (Specific Aim 1), iatrogenic factors (Specific Aim 2), and altered biomechanics (Specific Aim 3) affect dynamic cervical spine function following fusion. Participants will be C56 (n=22) and C67 (n=22) single-level fusion patients, C456 (n=22) and C567 (n=22) two-level fusion patients, and asymptomatic controls similar in age to the fusion patients (n=22). Patients will be tested prior to surgery, one year post-surgery, and three years post-surgery. At each test, participants will complete clinical questionnaires to assess pain and function, and they will perform full range of motion flexion\extension and axial rotation of the head and cervical spine while biplane radiographs are recorded at 30 images per second. A highly accurate and validated volumetric model- based tracking process and custom data analysis software will be utilized to determine intervertebral kinematics (i.e. translations, rotations, helical axis of motin) and arthrokinematics (i.e. disc deformation and facet joint surface interactions) at each test session. This prospective study will identify the factors that have the greatest effect on adjacent segment mechanics after cervical fusion. If the hypotheses are confirmed, this will provide support for increased attention to patient-specific factors and surgical technique. Alternatively, f the results indicate that adjacent segment mechanics are influenced primarily by increased stress after arthrodesis, this will provide support for increased attention to the design of motion sparing devices.