Uehara Masashi, Takahashi Jun, Ikegami Shota, Kuraishi Shugo, Futatsugi Toshimasa, Oba Hiroki, Takizawa Takashi, Munakata Ryo, Koseki Michihiko, Kato Hiroyuki
Department of Orthopaedic Surgery, Shinshu University School of Medicine, Matsumoto.
Faculty of Textile Science and Technology, Shinshu University, Tokida, Ueda, Nagano, Japan.
Clin Spine Surg. 2019 Apr;32(3):E166-E170. doi: 10.1097/BSD.0000000000000759.
Retrospective, single-center, single-surgeon study.
This study investigated screw perforation rate according to surface registration accuracy in pedicle screw fixation using a CT-based navigation system for adolescent idiopathic scoliosis (AIS).
Posterior spinal fusion for scoliosis correction using pedicle screws is widely adopted but carries a risk of serious neurovascular or visceral structure events. To attempt to avoid these complications, we have been using a computed tomography (CT)-based navigation system during screw insertion, although insufficient surface registration accuracy may be a reason for some screw perforations.
We evaluated 116 AIS patients (9 male and 107 females; mean±standard deviation age: 15.2±2.3 y) who had received pedicle screw fixation guided by a CT-based navigation system between August 2007 and December 2017. Screw perforation rate was evaluated in relation to surface registration accuracy and cut-off values were determined by receiver operating characteristic (ROC) curves.
A total of 1553 pedicle screws were inserted into T2-L4 vertebrae using CT-based navigation system. The respective overall perforation rates for grade 2 or 3 and grade 3 perforations by surface registration accuracy were 0.2 mm: 0% and 0%; 0.3 mm: 3.5% and 0%; 0.4 mm: 3.5% and 0.8%; 0.5 mm: 8.0% and 3.5%; 0.6 mm: 6.7% and 2.7%; 0.7 mm: 8.9% and 3.8%; 0.8 mm: 9.3% and 6.7%; and 0.9 mm: 9.3% and 4.7%. ROC curve analysis revealed a cut-off surface registration accuracy of 0.5 mm. The major screw perforation rate for a surface registration accuracy of ≥0.5 mm was significantly higher than that for <0.5 mm (P<0.01).
Analysis of screw perforation rate according to surface registration accuracy demonstrated a clinical cut-off of 0.5 mm. Thus, surface registration accuracy should optimally be <0.5 mm for scoliosis surgery with CT-based navigation system.
回顾性、单中心、单术者研究。
本研究使用基于CT的导航系统，针对青少年特发性脊柱侧凸（AIS）患者，调查椎弓根螺钉固定术中根据表面配准精度得出的螺钉穿孔率。
使用椎弓根螺钉进行脊柱后路融合术以矫正脊柱侧凸已被广泛采用，但存在发生严重神经血管或内脏结构相关事件的风险。为试图避免这些并发症，我们在螺钉植入过程中一直使用基于计算机断层扫描（CT）的导航系统，不过表面配准精度不足可能是一些螺钉穿孔的原因。
我们评估了2007年8月至2017年12月期间在基于CT的导航系统引导下接受椎弓根螺钉固定的116例AIS患者（9例男性，107例女性；平均年龄±标准差：15.2±2.3岁）。根据表面配准精度评估螺钉穿孔率，并通过受试者操作特征（ROC）曲线确定截断值。
使用基于CT的导航系统共向T2 - L4椎体植入了1553枚椎弓根螺钉。根据表面配准精度，2级或3级及3级穿孔的总体穿孔率分别为：0.2毫米：0%和0%；0.3毫米：3.5%和0%；0.4毫米：3.5%和0.8%；0.5毫米：8.0%和3.5%；0.6毫米：6.7%和2.7%；0.7毫米：8.9%和3.8%；0.8毫米：9.3%和6.7%；0.9毫米：9.3%和4.7%。ROC曲线分析显示表面配准精度的截断值为0.5毫米。表面配准精度≥0.5毫米时的主要螺钉穿孔率显著高于<0.5毫米时（P<0.01）。
根据表面配准精度对螺钉穿孔率进行分析显示临床截断值为0.5毫米。因此，对于基于CT导航系统的脊柱侧凸手术，表面配准精度最佳应<0.5毫米。
