下颈椎椎弓根瞄准器的研制与实验研究

目的：研制下颈椎椎弓根瞄准器并经实验确定其可行性。方法下颈椎椎弓根瞄准器主要由3个部分构成（竖杆连接于手术床边、万向可调节的中间连杆、可透 X 线的导针瞄准装置）；将6套共30个下颈椎干标本逐一固定于手术台，在 C 形臂 X 线机引导下，斜位45度（颈3～颈6）、40度（颈7）透视，沿导针轴线透视，使导针成点状投射到椎弓根圆形投影的中心，沿此中心钻入导针，再沿导针置入3．5 mm＆#215;28 mm 螺钉，取下标本检查螺钉置入的准确性。结果按 Neo 椎弓根螺钉评价标准，优良率达到90％（54/60枚椎弓根螺钉）。结论下颈椎椎弓根瞄准器设计原理可靠，经进一步的实验研究可逐步进入临床应用。

Design and experiment of the pedicle aiming device for the inferior cervical spine

Objective To design the pedicle aiming device for the inferior cervical spine and probe the accu-racy of the device by experiment.Methods First,design the pedicle aiming device for the inferior cervical spine,which consists of three portions （vertical pole which is connected to operating bed;intermediate connecting pole which can be adjusted to universal direction;guide pin device which is for X-ray filming）. Second,thirty dry specimen were fixed on the operating bed separately and were seen through fluoroscopy on a 45＆#176;line in cervical vertebra3 to cervical vertebra6 and on a 40＆#176;line in cervical vertebra7.After that, the guide pin became a point on the center of projective circle of the cervical pedicle through fluoroscopy on the line.Third,cervical pedicle was drilled a hole through the guide pin and 3.5 mm＆#215;28 mm screw was embedded in the hole.Finally,the accuracy of the screw was checked.Results The excellent rate of the screws was 90% （54/60）on the criterion of Neo.Conclusion Theory of the pedicle aiming device is reliable and the device can be applied to clinical practice after more experiments.