Optimizing Biomechanics of Surgical Correction for Lumbar Flatback Deformity

优化腰椎平背畸形手术矫正的生物力学

• 批准号: 10223462
• 负责人: Avinash G. Patwardhan
• 金额: --
• 依托单位: EDWARD HINES JR VA HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-07-01 至 2022-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10223462
• 关键词: Address; Adult; Affect; Age; Analysis of Variance; Anatomy; Back Pain; Biomechanics; Cadaver; Caring; Clinical; Clinical Research; Complex; Cone; Data; Deformity; Disease; Effectiveness; Equilibrium; Excision; Experimental Designs; Fatigue; Goals; Height; Hemorrhage; High Prevalence; Hip region structure; Human; Iatrogenesis; Implant; Incidence; Individual; Knee; Knowledge; Lead; Ligaments; Literature; Lordosis; Lumbar Curve; Measures; Methods; Morbidity - disease rate; Morphology; Muscle; Muscle Fatigue; Operative Surgical Procedures; Osteotomy; Outcome; Patients; Pelvis; Population; Posture; Procedures; Provider; Regression Analysis; Research; Risk; Shapes; Specific qualifier value; Specificity; Specimen; Statistical Data Interpretation; Stress; Surgeon; Techniques; Testing; Time; Translations; Vertebral column; Veterans; Walking; age related; arm; base; comorbidity; distraction; dorsal column; falls; flexibility; functional loss; improved; improved functioning; improved outcome; in vivo; military veteran; older patient; operation; response; restoration; sacrum; surgery outcome

Purpose: The long-term goal of this research is to improve the outcomes of surgical correction for lumbar flatback deformity, which is a complex disorder that can affect a large segment of the veteran population. In flatback deformity the torso pitches forward and affects the patient’s ability to stand upright and walk due to muscle fatigue and worsening back pain, leading to functional loss. The goal of surgery is to correct the sagittal malalignment to reduce muscle fatigue and allow patients to stand upright and ambulate, thus improving function. Surgeons who treat older veterans want to know: (1) how much lordosis restoration is sufficient to reduce the burden on muscles to maintain an upright posture; and (2) can this be achieved using a less invasive surgical technique to minimize complications and morbidity. Hypothesis: Our central hypothesis is that restoring lumbar lordosis using lordotic interbody fusion cages implanted in multiple disc spaces will minimize the forces needed to maintain an upright posture in specimens with loss of lordosis across L4 to sacrum. Specific aims: (1) We will use human cadaveric thoracolumbar (T10-sacrum) spine specimens with a range of PI values (35°-70°; the average adult PI is 52°) to quantify the shear force and moment required at the cephalad and caudal boundaries of the specimen to maintain an upright standing posture under the following conditions: (1) hypolordosis across L4-S1, creating a PI-LL mismatch (degenerative or iatrogenic), and (2) improvement of L1-S1 lordosis using lordotic interbody fusion cages placed at one or more segments of the lumbar spine, first without and then with posterior column (facet) osteotomies (PCO). (2) We will analyze the data collected in aim 1 to: (1) define a relationship between the extent of PI-LL mismatch and forces needed to maintain an upright standing posture for the reconstructed spines, and (2) quantify the influence of the following study variables on the ability of lordotic interbody cages to improve standing lumbar lordosis: (a) number of reconstructed disc spaces, (b) specimen’s PI value and flexibility (that is, segmental mobility in flexion and extension), (c) influence of PCO to yield additional correction. Methods: The experimental design consists of two arms: degenerative, and iatrogenic. In the iatrogenic arm, a hypolordotic fusion across L4-S1 will be created by applying distraction forces across pedicle screws inserted in L4, L5 and S1 pedicles; whereas, in the degenerative arm we will select specimens in which there is sufficient loss of disc heights at the L5-S1 and L4-L5 disc spaces. In the iatrogenic arm, surgical restoration of L1-S1 lordosis will be performed by implanting lordotic interbody cages at L3-L4 and L2-L3 disc spaces cephalad to the hypolordotic L4-S1 fusion; whereas, in the degenerative arm surgical restoration of segmental lordosis will be performed at L5-S1 and L4-L5 disc spaces. In both arms of the study, we will aim to eliminate the PI-LL mismatch (PI-LL ≤5°) by adding additional segments where lordotic interbody cages are implanted and, if necessary, performing posterior column (facet) osteotomies to augment the correction potential of interbody cages. In each state the specimens will undergo a battery of biomechanical tests to quantify the shear force and moment required at the cephalad and caudal boundaries of the specimen to maintain an upright posture. Statistical analysis will include repeated-measures ANOVA and multivariate regression analyses. Clinical Impact: The overall percentage of living Veterans expected to be affected by flatback deformity is anticipated to rise as the population ages and lives longer. Thus, the contribution of the proposed research to the knowledge of VA providers who care for our Veterans is likely significant. If the biomechanical data supports the use of segmental lordosis restoration using interbody fusion cages, the less invasive technique will add a valuable option for restoring lumbar lordosis in older patients. The research results are readily applicable for quick translation to veteran- and civilian patients if found to be beneficial.

目的：这项研究的长期目标是改善腰椎手术校正的结果 扁平畸形，这是一种复杂的疾病，可以影响退伍军人人口的大部分。在 屈服畸形向前伸出躯干，并影响患者直立和行走的能力 肌肉疲劳和后悔背痛，导致功能损失。手术的目的是纠正矢状 恶意减少肌肉疲劳并允许患者直立和行动，从而改善 功能。治疗老年退伍军人的外科医生想知道：（1）洛里森的修复足以 减少肌肉上的燃烧以保持直立的姿势； （2）可以使用较小的侵入性来实现这一点 手术技术可最大程度地减少并发症和发病率。 假设：我们的中心假设是使用主体间融合笼恢复腰椎脊柱 植入多个圆盘空间将最大程度地减少在标本中保持直立姿势所需的力 在整个L4到ac骨上失去了脊椎病。 具体目的：（1）我们将使用人类尸体胸胸骨（T10-SACRUM）标本 PI值（35°-70°；平均成年PI为52°），以量化Cephalad所需的剪切力和矩 和标本的尾端边界，以在以下条件下保持直立的姿势： （1）跨L4-S1的低调，产生PI-LL不匹配（退化性或医源性），以及（2）改善 L1-s-s1 lordosis使用lordotototototod室间融合笼，放在腰椎的一个或多个段，首先 没有后柱（Facet）截骨术（PCO）。 （2）我们将分析AIM 1中收集的数据至：（1）定义PI-LL不匹配程度之间的关系 以及为重建的刺维保持直立的站立姿势所需的力，（2）量化 以下研究变量对洛里菌间跨笼子改善腰椎的能力的影响 Lordosis：（a）重建的圆盘空间数量，（b）标本的PI值和灵活性（即分段 屈曲和扩展中的迁移率），（c）PCO对额外校正的影响。 方法：实验设计由两个臂组成：退化性和医源性。在医源臂中 通过在插入的椎弓根螺钉上施加干扰力来创建跨L4-S1的低调融合 L4，L5和S1椎弓根；而在退化臂中，我们将选择有足够损失的标本 L5-S1和L4-L5圆盘空间处的圆盘高度。在医源臂中，L1-S1 Lordosis的手术恢复 将通过在L3-L4处植入Lordotototototy室内笼子和L2-L3圆盘空间来执行Cephalad 低调L4-S1融合；而在退化性手臂手术恢复中，则将对节叶的遗传恢复是 在L5-S1和L4-L5圆盘空间上进行。在研究的两个臂中，我们将旨在消除Pi-ll不匹配 （pi-ll≤5°）通过添加植入主体室内笼的其他片段，并在必要时， 执行后柱（方面）截骨术以增强体式笼子的校正潜力。每个 说明样品将经过一系列生物力学测试，以量化剪切力和力矩 在标本的头和尾端边界需要保持直立的姿势。 统计分析将包括重复测量方差分析和多元回归分析。 临床影响：预计将受到倒篮畸形影响的活着退伍军人的总百分比为 预计随着人口的年龄和寿命更长的时间而上升。那，拟议的研究对 关心退伍军人的VA提供者的知识可能是重要的。如果生物力学数据支持 使用分段的脊柱叶子恢复使用室内融合笼，侵入性技术较少会增加 在老年患者中恢复腰肌的价值选择。研究结果很容易适用 如果发现有益，请快速翻译为资深和平民患者。