Lin Xi, Ai Fu Zhi, Yin Qing Shui, Xia Hong, Wu Zeng Hui, Ma Xiang Yang
Department of Orthopedics, Fujian Provincial Hospital, Fuzhou, China; Department of Orthopedics, Liu-Hua-Qiao Hospital, Guangzhou, China.
Department of Orthopedics, Liu-Hua-Qiao Hospital, Guangzhou, China.
Acta Orthop Traumatol Turc. 2014;48(3):298-302. doi: 10.3944/AOTT.2014.13.0005.
The aim of this study was to describe the application of the rapid prototyping (RP) life-size 3-dimensional model used to improve accuracy of screw insertion in irreducible atlanto-axial dislocation (IAD).
The study included 10 patients with IAD. All patients were assessed using the Japanese Orthopedic Association (JOA) score. Radiographs, MRI and CT were conducted during the preoperative and postoperative procedure. A 3D RP model was created for each patient. The model was used to obtain detailed information of each pedicle and used as an intraoperative reference. Assisted by the model, transoral atlanto-axial reduction plate fixation was performed in each case.
The average operation time was 145 (range: 90 to 180) minutes and average blood loss was 120 (range: 60 to 250) ml. JOA scores improved after surgery. All 40 transoral pedicle/lateral mass screws were placed without serious complications or internal fixation failure. Postoperative radiographs and CT scan showed 38 transoral pedicle/lateral mass screws located in the pedicle tracts. Satisfactory reduction was achieved in 95% of screws. Two screws perforated the lateral wall of the C2 pedicles in an extremely narrow pedicle case. No neurologic sequelae or vertebral artery injury were detected.
The RP technique is effective and reliable in achieving an accurate and safe screw insertion during IAD surgery, especially in anatomically abnormal cases.
本研究旨在描述快速成型（RP）实物大小三维模型在提高难复性寰枢椎脱位（IAD）螺钉置入准确性方面的应用。
该研究纳入10例IAD患者。所有患者均采用日本骨科协会（JOA）评分进行评估。术前和术后均进行了X线片、MRI和CT检查。为每位患者创建了一个三维RP模型。该模型用于获取每个椎弓根的详细信息，并用作术中参考。在该模型的辅助下，对每例患者进行经口寰枢椎复位钢板固定。
平均手术时间为145（范围：90至180）分钟，平均失血量为120（范围：60至250）毫升。术后JOA评分有所改善。所有40枚经口椎弓根/侧块螺钉置入均无严重并发症或内固定失败。术后X线片和CT扫描显示38枚经口椎弓根/侧块螺钉位于椎弓根通道内。95%的螺钉实现了满意的复位。在1例椎弓根极窄的病例中，有2枚螺钉穿透了C2椎弓根的侧壁。未发现神经后遗症或椎动脉损伤。
RP技术在IAD手术中实现准确、安全的螺钉置入方面是有效且可靠的，尤其是在解剖结构异常的病例中。
