Adjacent Segment Mechanics in Cervical Arthrodesis Patients

 描述（由申请方提供）：在美国，颈椎前路椎间盘切除融合术（ACDF）是治疗退行性颈椎疾病的最常见手术。不幸的是，ACDF不能防止初次手术邻近运动节段的退化（即邻近节段疾病），大约25%的患者在初次手术后10年内需要再次手术。本研究旨在确定可能增加相邻节段退变风险的因素。这项研究可能有助于通过减少再次手术来减少医疗保健支出，并提高患者的安全性和生活质量。翻译后摘要：颈椎融合后相邻节段病理的病因仍然存在很大争议。相邻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）相邻椎间盘的自然病史; 2）相邻节段的破坏 由于初次手术导致的解剖结构; 3）融合后相邻节段上的生物力学应力。我们研究的长期目标是减少或预防脊柱相邻节段退变的症状。本研究的总体假设是ACDF后相邻节段运动学（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）主要由患者特定解剖结构和医源性因素决定，而不是由融合引起的生物力学应力增加决定。提出了一项前瞻性纵向研究，以确定患者特异性因素（特定目标1）、医源性因素（特定目标2）和生物力学改变（特定目标3）对融合后动态颈椎功能的影响程度。受试者为C56（n=22）和C67（n=22）单节段融合患者、C456（n=22）和C567（n=22）双节段融合患者以及年龄与融合患者相似的无症状对照（n=22）。患者将在手术前、手术后一年和手术后三年接受测试。在每次测试中， 参加者将填写临床问卷以评估疼痛和功能，并进行头部和颈椎的全方位活动屈曲/伸展和轴向旋转，同时以每秒30张图像的速度记录双平面X光片。将使用高度准确且经确认的基于体积模型的跟踪过程和定制数据分析软件来确定每次测试时的椎间运动学（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）。这项前瞻性研究将确定对邻近地区影响最大的因素。 颈椎融合后的节段力学。如果假设得到证实，这将为增加对患者特定因素和手术技术的关注提供支持。或者，如果结果表明关节融合术后相邻节段力学主要受应力增加的影响，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.