Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Health System, Washington, DC, USA.
Orthopaedic Surgery Department, Johns Hopkins Medicine, Baltimore, MD, USA.
Int J Comput Assist Radiol Surg. 2022 Dec;17(12):2263-2267. doi: 10.1007/s11548-022-02705-0. Epub 2022 Aug 20.
Manual surgical manipulation of the tibia and fibula is necessary to properly align and reduce the space in ankle fractures involving sprain of the distal tibiofibular syndesmosis. However, manual reduction is highly variable and can result in malreduction in about half of the cases. Therefore, we are developing an image-guided robotic assistant to improve reduction accuracy. The purpose of this study is to quantify the forces associated with reduction of the ankle syndesmosis to define the requirements for our robot design.
Using a cadaveric specimen, we designed a fixture jig to fix the tibia securely on the operating table. We also designed a custom fibula grasping plate to which a force-torque measuring device is attached. The surgeon manually reduced the fibula utilizing this construct while translational and rotational forces along with displacement were being measured. This was first performed on an intact ankle without ligament injury and after the syndesmosis ligaments were cut.
Six manipulation techniques were performed on the three principal directions of reduction at the cadaveric ankle. The results demonstrated the maximum force applied to the lateral direction to be 96.0 N with maximum displacement of 8.5 mm, applied to the anterior-posterior direction to be 71.6 N with maximum displacement of 10.7 mm, and the maximum torque applied to external-internal rotation to be 2.5 Nm with maximum rotation of 24.6°.
The specific forces needed to perform the distal tibiofibular syndesmosis manipulation are not well understood. This study quantified these manipulation forces needed along with their displacement for accurate reduction of ankle syndesmosis. This is a necessary first step to help us define the design requirements of our robotic assistance from the aspects of forces and displacements.
在涉及下胫腓联合扭伤的踝关节骨折中，需要手动操作胫骨和腓骨以正确对齐并减小间隙。然而，手动复位的可变性很高，大约有一半的病例会出现复位不良。因此，我们正在开发一种图像引导的机器人辅助系统，以提高复位的准确性。本研究的目的是量化踝关节下胫腓联合复位相关的力，以确定我们机器人设计的要求。
使用尸体标本，我们设计了一个固定装置夹具，将胫骨牢固地固定在手术台上。我们还设计了一个定制的腓骨抓握板，其上附有一个力-扭矩测量装置。外科医生使用这个结构手动复位腓骨，同时测量沿三个方向的平移和旋转力以及位移。这首先在没有韧带损伤的完整踝关节上进行，然后再在下胫腓联合韧带切断后进行。
在尸体踝关节的三个主要复位方向上进行了六种操作技术。结果表明，在外侧方向施加的最大力为 96.0 N，最大位移为 8.5 mm；在前-后方向施加的最大力为 71.6 N，最大位移为 10.7 mm；在外-内旋转方向施加的最大扭矩为 2.5 Nm，最大旋转角度为 24.6°。
对于执行下胫腓联合操作所需的特定力，我们了解得还不够清楚。本研究量化了这些复位力及其位移，以准确复位踝关节下胫腓联合。这是从力和位移方面帮助我们确定机器人辅助设计要求的必要的第一步。
