Schwarzenbach O, Berlemann U, Jost B, Visarius H, Arm E, Langlotz F, Nolte L P, Ozdoba C
Department of Orthopaedic Surgery, Inselspital, Bern, Switzerland.
Spine (Phila Pa 1976). 1997 Feb 15;22(4):452-8. doi: 10.1097/00007632-199702150-00020.
A computer-assisted planning and visualization system (the Orthopaedic Surgery Planning System) was tested for pedicle screw insertion in vivo.
To evaluate the system's applicability for regular intraoperative use and its accuracy for pedicle screw placement in vivo.
Pedicle screw placement poses considerable anatomic and biomechanical risks. The reported rates of screw misplacement with conventional insertion techniques are unacceptably high. It previously has been shown in vitro that computer assistance offers the potential to decrease the number of screws perforating the pedicular cortex.
The accuracy of 162 pedicle screws inserted with the Orthopaedic Surgery Planning System was assessed by means of postoperative computed tomography evaluation. Reconstructions of the horizontal, frontal, and sagittal planes were analyzed. Cortex perforations were graded in steps of 2 mm.
The cortex was perforated in 2.7% of pedicles. Complete preoperative computed tomography scanning of the levels to be operated on is essential to allow for a precise image reconstruction. Initial difficulties in applying the system contribute to the malplacements. A learning curve for general handling of the Orthopaedic Surgery Planning System was observed.
The system provides a safe and reproducible technique for pedicle screw insertion. Other applications in the field of spine surgery are under evaluation.
对一种计算机辅助规划与可视化系统（骨科手术规划系统）进行了体内椎弓根螺钉置入测试。
评估该系统在常规术中使用的适用性及其在体内椎弓根螺钉置入的准确性。
椎弓根螺钉置入存在相当大的解剖学和生物力学风险。报道的传统置入技术导致螺钉误置的发生率高得令人难以接受。此前体外研究表明，计算机辅助有潜力减少穿透椎弓根皮质的螺钉数量。
通过术后计算机断层扫描评估，对使用骨科手术规划系统置入的162枚椎弓根螺钉的准确性进行评估。分析水平、 frontal和矢状面的重建图像。皮质穿孔按2毫米步长分级。
2.7%的椎弓根发生皮质穿孔。对拟手术节段进行完整的术前计算机断层扫描对于精确的图像重建至关重要。应用该系统时最初的困难导致了误置。观察到了骨科手术规划系统一般操作的学习曲线。
该系统为椎弓根螺钉置入提供了一种安全且可重复的技术。正在评估其在脊柱外科领域的其他应用。
