3D打印骨折模型在股骨转子间骨折治疗中的应用

Application of 3D printing fracture models in treatment of intertrochanteric fracture

目的探讨3D打印骨折模型在股骨转子间骨折治疗中的应用效果。方法回顾性分析2014年8月至2015年2月期间采用股骨近端防旋髓内钉（PFNA）治疗的27例不稳定型股骨转子间骨折患者资料，根据术前是否应用3D打印技术分为2组：3D模型组12例，非3D模型组15例。3D模型组患者术前行64排螺旋CT扫描，对所获Dicom格式数据使用M3D数字医学软件进行三维重建，生成STL文件后导入3D打印机进行模型制造。基于3D打印模型制定手术方案、规划PFNA固定并与术中实际结果进行比较。记录患者的手术时间、术中出血量、术后引流量、住院时间及末次随访时髋关节Harris评分，并与非3D模型组进行比较。结果3D模型组术前规划与术中使用的PFNA主钉直径[（9．42±0．64）、（9．58±0．76）mm]、主钉长度[（177．50±12．90）、（178．33±20．34）mm]、螺旋刀片长度[（84．58±5．94）、（85．42±5．57）mm]比较差异均无统计学意义（P〉0．05）。27例患者术后获平均12．4个月（10-16个月）随访。3D模型组患者的手术时间[（47．8±5．1）min]、术中出血量[（101．6±3．9）mL]、术后引流量[（47．3±5．9）mL]显著少于非3D模型组患者[（61．1±7．5）mn、（122．3±9．8）mL、（58．6±6．3）mL]），差异均有统计学意义（P〈0．05）；而两组患者的住院时间、末次随访时髋关节Harris评分比较差异均无统计学意义（P〉0．05）。两组患者骨折均愈合良好，无髋内翻畸形、内固定失败等并发症发生。结论3D打印可准确构建股骨转子间骨折的原型，有利于骨折的精确复位，可提高手术精度、缩短手术时间，达到更佳的手术效果。

Objective To report the application of 3D printing fracture models to assist the treatment of femoral intertrochanteric fracture using proximal femoral nail anti-rotation （PFNA） fixation. Methods From August 2014 to February 2015, 27 unstable intertroehanterie fractures were treated using PFNA. Of them, 12 used a 3D printing fracture model to assist the surgery and 15 did not. CT scanning was performed for the patients in 3D printing model group. Their anatomical data of. Dicom form were reconstructed into the. STL form data through M3D software. The 3D printing model was constructed using fused deposition modeling （FDM） technique. The length and diameter of the main screw and blade were measured based on the 3D printing prototyping before surgical planning. The 2 groups were compared in terms of operation time, intraoperative blood loss, postoperative drainage volume, hospital stay and Harris hip score at the final follow-up. Results No significant differences were found in the 3D printing model between surgical planning and actual operation in the respects of diameter of main PFNA screw （9.42 ± 0.64 mm versus 9.58 ± 0. 76 ram）, length of main PFNA screw （177.50±12.90 mm versus 178.33±20.34 mm）, or length of blade （84.58±5.94 mm versus 85.42 ±5.57 ram） （P 〉 0. 05）. The 27 patients obtained an average follow-up of 12.4 months （from 10 to 16 months）. The operation time （47.8 ± 5.1 min）, intraoperative blood loss （101.6 ± 3.9 mL） and postoperative drainage volume （47. 3 ± 5.9 mL） in the 3D printing model group were significantly less than those in the conventional group （61.1 ±7.5 min, 122.3 ±9.8 mL and 58.6 ±6.3 mL, respectively） （ P 〈 0.05）. There were no significant differences between the 2 groups in hospital stay or Harris hip score at the final follow-up （ P 〉 O. 05）. Both groups obtained fine fracture union. No varus deformation of the hip joint or failure of implants was observed during the follow-up period. Conclusion 3D printing technique can manufacture an accurate model of intertrochanteric fracture, which may play an important role in improving efficiency and accuracy of reduction and PFNA fixation.