Nagashima Katsuya, Koda Masao, Abe Tetsuya, Kumagai Hiroshi, Miura Kousei, Fujii Kengo, Noguchi Hiroshi, Funayama Toru, Miyamoto Takuya, Mannoji Chikato, Furuya Takeo, Yamazaki Masashi
Department of Orthopedic Surgery, University of Tsukuba, Tsukuba, Japan.
Department of Orthopedic Surgery, University of Tsukuba, Tsukuba, Japan.
J Clin Neurosci. 2019 May;63:106-109. doi: 10.1016/j.jocn.2019.01.029. Epub 2019 Jan 31.
The aim of this study was to investigate the incidence and characteristics of implant failure in posterior cervical long-segment fusion surgery. We retrospectively reviewed 51 cases of posterior cervical long-segment fusion surgery that used pedicle screws, lateral mass screws, or laminar screws. The cranial end of the fusion was C2 or C3, and the caudal end of the fusion was C7 or T1. All patients were observed with CT scans at 6 months postoperatively. We evaluated the loosening and breakage of the implanted screws or rods. In the 51 patients, 257 pedicle screws, 9 laminar screws and 233 lateral mass screws were placed. Implant failure occurred in 25 patients (49.0%). Screw loosening was found in 42 screws (8.4%). Screw breakage occurred in 6 (1.2%) screws. The implant failures were particularly observed in both ends of the fusion level. When C7 was the end of the lower instrumented level, the incidence was 40% without C6 pedicle screws, 33% with unilateral C6 pedicle screws, and 0% with bilateral C6 pedicle screws. The present study revealed that the incidence of implant failures of the screws in long-segment posterior cervical fusion surgery was higher, especially in the caudal end of the fusion levels. In cases where C7 was the lowest instrumented vertebra, buttress screw insertion to C6 is recommended to avoid implant failure of C7 pedicle screws.
本研究的目的是调查颈椎后路长节段融合手术中植入物失败的发生率及特征。我们回顾性分析了51例行颈椎后路长节段融合手术的病例，这些手术使用了椎弓根螺钉、侧块螺钉或椎板螺钉。融合的头端为C2或C3，尾端为C7或T1。所有患者均在术后6个月行CT扫描观察。我们评估了植入螺钉或棒的松动及断裂情况。51例患者共置入257枚椎弓根螺钉、9枚椎板螺钉和233枚侧块螺钉。25例患者（49.0%）出现植入物失败。发现42枚螺钉（8.4%）出现螺钉松动。6枚螺钉（1.2%）发生螺钉断裂。植入物失败尤其在融合节段的两端观察到。当C7为下固定节段的末端时，未置入C6椎弓根螺钉时发生率为40%，单侧置入C6椎弓根螺钉时为33%，双侧置入C6椎弓根螺钉时为0%。本研究表明，颈椎后路长节段融合手术中螺钉植入物失败的发生率较高，尤其是在融合节段的尾端。在以C7为最低固定椎体的病例中，建议向C6置入支撑螺钉以避免C7椎弓根螺钉植入物失败。
