Department of Orthopedic Surgery, Shinshu University School of Medicine, Matsumoto, Japan.
Knee Surg Sports Traumatol Arthrosc. 2011 Mar;19(3):378-83. doi: 10.1007/s00167-010-1217-y. Epub 2010 Jul 17.
Accurate placement of separate anteromedial and posterolateral bundle bone tunnels is crucial for anatomic, double-bundle anterior cruciate ligament (ACL) reconstruction. However, identifying the anatomic footprint at which to make the tibial and femoral bone tunnels is not a straightforward procedure. To overcome this problem, we used a CT-based navigation technique with a registration procedure based on fiducial markers (FMs).
Preoperatively, 10 FM points were placed on skin around knee joint and scanned with CT. Imaging data of the knee were recorded on the computer system for preoperative registration and surgical planning. Intraoperatively, with a reference frame fixed to the distal medial aspect of femur and tibia, paired-point matching registration was performed with the use of points marked on skin through FM center holes. During tibial tunnel guide wire placement, tibial aiming guide with tracking device fed back the position of tip and direction of the guide wire on the three-dimensional (3D) tibia bone surface image and multiple image planes in real time. For the femoral side, the navigation pointer was placed at the footprint center with visual guidance of 3D image of lateral wall sagittal view on navigation monitor and marked with navigation awl.
The average registration accuracy of 22 consecutive patients was 0.7 ± 0.2 mm and 0.6 ± 0.2 mm for femoral and tibial bone, respectively. Most of the bone tunnel positions evaluated with 3D-CT image were confirmed to be accurately placed in reference to the preoperative plan. There was no damage to femoral condyle cartilage and no other complication.
This new CT-based computer navigation system opens the possibility for surgeons to plan bone tunnel positioning preoperatively and control it during technically demanding anatomic double-bundle ACL reconstruction.
准确放置分体式前内侧束和后外侧束骨隧道对于解剖学双束前交叉韧带（ACL）重建至关重要。然而，确定用于制作胫骨和股骨骨隧道的解剖学足迹并不是一个简单的过程。为了解决这个问题，我们使用了一种基于 CT 的导航技术，该技术具有基于基准标记（FM）的注册程序。
术前，将 10 个 FM 点放置在膝关节周围的皮肤上并用 CT 扫描。将膝关节的成像数据记录在计算机系统上，用于术前注册和手术规划。术中，在股骨和胫骨的远端内侧固定参考框架，通过 FM 中心孔标记的点进行配对点匹配注册。在胫骨隧道导丝放置过程中，带有跟踪装置的胫骨瞄准引导器实时反馈导丝尖端的位置和方向在三维（3D）胫骨骨表面图像和多个图像平面上。对于股骨侧，导航指针在导航监视器上的外侧壁矢状视图的 3D 图像的视觉引导下放置在足迹中心，并使用导航锥标记。
22 例连续患者的平均注册精度分别为股骨和胫骨的 0.7±0.2mm 和 0.6±0.2mm。用 3D-CT 图像评估的大多数骨隧道位置都被证实准确地放置在术前计划中。没有对股骨髁软骨造成损伤，也没有其他并发症。
这种新的基于 CT 的计算机导航系统为外科医生提供了在术前计划骨隧道定位并在技术要求高的解剖学双束 ACL 重建过程中控制它的可能性。
