Objective: To investigate the clinical application of three-dimensional (3D) printing technique combined with a new type of thoracic pedicle screw track detector in thoracic pedicle screw placement.
Methods: According to the characteristics of thoracic pedicle and common clinical screw placement methods, a new type of thoracic pedicle screw track detector was independently developed and designed. The clinical data of 30 patients with thoracic vertebrae related diseases who underwent posterior thoracic pedicle screw fixation between March 2017 and January 2020 were retrospectively analysed. Among them, there were 18 males and 12 females with an average age of 56.3 years (range, 32-76 years). There was 1 case of thoracic disc herniation, 4 cases of thoracic canal stenosis, 2 cases of ossification of posterior longitudinal ligament of thoracic vertebra, 16 cases of thoracic trauma, 2 cases of thoracic infection, and 5 cases of thoracic canal occupation. Three-dimensional CT of the thoracic vertebra was routinely performed preoperatively, and the model of the patient's thoracic vertebra was reconstructed and printed out. With the assistance of the model, preoperative simulation was performed with the combination of the new type thoracic pedicle screw track detector, and detected no nails after critical cortical damage. During operation, one side was randomly selected to use traditional hand screws placement (control group), and the other side was selected to use 3D printing technique combined with new type thoracic pedicle screw track detector to assist thoracic pedicle screws placement (observation group). The single screw placement time, adjustment times of single screw, and blood loss during screw placement were compared between the two groups. The accuracy of screw placement in the two groups was evaluated according to postoperative CT imaging data.
Results: The single screw placement time, adjustment times of single screw, and blood loss during screw placement in the observation group were significantly less than those in the control group ( P<0.05). Postoperative CT examination showed that the observation group had 87 screws of grade 1, 3 screws of grade 2, and the acceptable screw placement rate was 100% (90/90); the control group had 76 screws of grade 1, 2 screws of grade 2, 11 screws of grade 3, and 1 screw of grade 4, and the acceptable screw placement rate was 86.7% (78/90); showing significant difference in screw placement between the two groups ( χ 2=12.875, P=0.001). All patients were followed up 6-18 months, with an average of 11.3 months. There was no complication of vascular, nerve, spinal cord, or visceral injury, and screws or rods broken, and no patient was revised.
Conclusion: The 3D printing technique combined with the new type of thoracic pedicle screw track detector assisted thoracic pedicle screw placement is convenient, and significantly improves the accuracy and safety of intraoperative screw placement, and overall success rate of the surgery.
目的: 探讨 3D 打印技术结合一种新型胸椎椎弓根螺钉钉道探测器辅助胸椎椎弓根植钉的安全性及准确性。.
方法: 根据胸椎椎弓根特点及临床常用植钉方法，自主研发一种新型胸椎椎弓根螺钉钉道探测器。回顾分析 2017 年 3 月—2020 年 1 月行后路胸椎椎弓根螺钉固定手术的 30 例胸椎相关疾病患者临床资料。其中男 18 例，女 12 例；年龄 32～76 岁，平均 56.3 岁。胸椎间盘突出症 1 例，胸椎管狭窄症 4 例，胸椎后纵韧带骨化症 2 例，胸椎外伤 16 例，胸椎感染疾病 2 例，胸椎管占位 5 例。术前常规行胸椎三维 CT，重建并 3D 打印患者胸椎模型，在模型辅助下结合新型钉道探测器进行术前模拟，探测器检测无关键皮质破损后植钉。术中随机选择一侧采用传统徒手植钉（对照组），另一侧采用 3D 打印技术结合新型胸椎椎弓根螺钉钉道探测器辅助植钉（观察组）。比较两组术中单枚螺钉植钉时间、单枚螺钉调整次数及植钉过程出血量；并根据术后 CT 影像学资料评价两组螺钉植入准确性。.
结果: 观察组单枚螺钉植钉时间、单枚螺钉调整次数、植钉过程出血量均显著少于对照组（ P<0.05）。术后 CT 检查示，观察组 1 级螺钉 87 枚，2 级螺钉 3 枚，可接受植钉率为 100%（90/90）；对照组 1 级螺钉 76 枚，2 级螺钉 2 枚，3 级螺钉 11 枚，4 级螺钉 1 枚，可接受植钉率为 86.7%（78/90）；两组植钉情况比较差异有统计学意义（ χ 2=12.875， P=0.001）。所有患者均获随访，随访时间 6～18 个月，平均 11.3 个月。两组均无血管、神经、脊髓、内脏损伤及断钉、断棒等并发症发生，无翻修患者。.
结论: 3D 打印技术结合新型椎弓根螺钉钉道探测器辅助植钉，操作便捷，可显著提高术中植钉的准确性、安全性及手术整体成功率。.
Keywords: Three-dimensional printing technique; internal fixation; pedicle screw; screw track detector; thoracic spine.