A Neurosurgical Robotic System for Minimally Invasive Spinal Fusion of Osteoporotic Vertebrae Using Flexible Pedicle Screws

总结/摘要： 我们的长期目标是开发一种新型的半自主，微创，图像引导的神经外科手术 机器人工作站，由机器人定位机构、连续操作器、柔性 器械，和柔性植入物（即，柔性椎弓根螺钉（FPS）），以实现下一代最小- 和微创脊柱介入治疗通过提供进入椎体内区域的通道，目前， 无法使用传统的刚性手术器械，这种神经外科机器人工作站将使 脊柱中各种骨缺损如脊髓和/或神经根上的压迫的外科治疗， 转移性骨疾病和由于严重骨质疏松导致的椎骨压缩性骨折。对于这个项目，我们 主要集中在机械设计，开发，基本控制，和评估的子系统， 这种新型机器人系统的目标是微创脊柱融合的脊椎骨。 大约5400万50岁及以上的美国人患有骨质疏松症， 每年骨折的人数仅在美国。脊椎骨折是脊椎骨骨折中最常见的类型 （约47%），这可能导致背痛，身高下降，以及进一步的脊椎和非脊椎骨折。失败 的非手术治疗往往导致脊柱融合手术，以恢复稳定的脊柱使用刚性 椎弓根螺钉（RPS）。然而，解剖学约束和器械和螺钉的刚性迫使 外科医生通常将螺钉植入椎骨的低骨矿物质密度（BMD）区域内， 脊柱畸形。这导致螺钉松动、拔出和随后手术的风险增加 失败 我们的中心假设是，利用所提出的微创机器人系统， 使用RPS的脊柱融合可以得到显著改善。这一改进将通过以下方式实现：（i）制定一项 生物力学分析模块，用于基于椎骨中的空间（3D）BMD来规划弯曲的钻孔轨迹 通过QCT扫描获得;（ii）增加外科医生的可达性，使他们能够在高BMD中钻孔 使用可操纵的钻孔机器人和弯曲钻孔技术的椎骨区域;（iii）选择性地 - 将FPS植入/锚定在高BMD区域内的预先计划的钻孔弯曲轨迹内， （4）FPS植骨融合的生物力学分析 和/或骨水泥，以优化脊柱稳定性，防止椎骨塌陷，并需要翻修手术。 拟议的贡献是重要的，高影响力和创新，因为它提出消除 通过提出新的和创新的技术来解决当前脊柱融合手术的上述并发症。到 根据我们的知识，利用导向钻井机器人和FPS的机器人辅助技术还没有被 用于微创脊柱融合术治疗脊椎骨骨折。我们的目标是证明 所提出的系统可以显著地改善目前对脊椎骨退行性变的治疗， 临床范例

Summary/Abstract: Our long-range goal is to develop a novel semi-autonomous, minimally-invasive, image-guided neurosurgical robotic workstation that consists of a robotic positioning mechanism, a continuum manipulator, flexible instruments, and flexible implants (i.e., flexible pedicle screws (FPSs)) to enable the next generation of minimally- and less-invasive spinal interventions. By providing access to regions within vertebral body, which currently are not accessible utilizing conventional rigid surgical instruments, this neurosurgical robotic workstation will enable surgical treatment of various bone defects in spine such as compression on the spinal cord and/or nerve roots, metastatic bone disease, and vertebral compression fractures due to severe osteoporosis. For this project, we mainly will focus on the mechanical design, development, basic control, and assessment of the subsystems of this novel robotic system with the goal of minimally invasive spinal fusion of osteoporotic vertebrae. Approximately 54 million Americans age 50 and older have osteoporosis causing an estimated two million broken bones per year in the US only. Vertebral fractures are the most common type of osteoporotic fractures (about 47%), which can lead to back pain, loss of height, and further vertebral and non-vertebral fractures. Failure of non-surgical treatments often leads to a spinal fusion surgery to restore stability of the spine using Rigid Pedicle Screws (RPSs). However, anatomical constraints and rigidity of instruments and screws force the surgeon to typically implant the screw inside the low bone mineral density (BMD) regions of the vertebrae in an osteoporotic spine. This results in an increased risk of screws loosening, pullout, and subsequently a surgical failure. It is our central hypothesis that utilizing the proposed minimally-invasive robotic system, the success rate of spinal fusions with RPSs can be significantly improved. This improvement will happen by (i) developing a biomechanical analysis module to plan a curved drilling trajectory based on the spatial (3D) BMD in the vertebra obtained by QCT scans; (ii) increasing the reachability of the surgeons and enabling them to drill in high-BMD regions of vertebra using a steerable drilling robot and the curved-drilling technique; (iii) selectively implanting/anchoring the FPSs within the pre-planned drilled curved trajectories inside the high-BMD regions, which can improve the pullout strength and stability of fusion; (iv) Biomechanical analysis of the fusion with FPS and/or bone cemnet to optimize the spine stability, prevent vertebral collapse, and a need for revision surgery. The proposed contribution is significant, high impact, and innovative since it offers to eliminate the aforementioned complications of current spinal fusion surgery by proposing novel and innovative techniques. To our knowledge, robotically-assisted techniques utilizing a steerable drilling robot and FPSs have not been developed for a minimally invasive spinal fusion of osteoporotic vertebrae. Our goal is to demonstrate that the proposed system can significantly improve the current treatment of osteoporotic vertebrae and shift the current clinical paradigm.