寰枕关节后路经关节螺钉固定钉道参数的测定

The measurement of trajectory parameters in posterior atlanto-occipital transarticular screw fixation

目的 明确后路寰枕关节经关节螺钉固定的技术参数;探讨枕颈部经关节螺钉内固定技术的临床意义。方法 30例含完整寰枕关节干燥骨性标本,直视下行后路寰枕关节经关节克氏针植入后行X线摄片,在X线胶片上测量寰枕关节经关节螺钉固定的钉道角度和钉道长度。结果 寰枕关节经关节螺钉固定的钉道理想角度为:螺钉方向在矢状面的上倾角为 53. 3°±3. 4°,在冠状面的内倾角为 20. 0°±2. 6°。钉道长度为: (29. 28±2. 46)mm。结论 寰枕关节后路经关节螺钉植入存在一定的方向性和钉道长度问题,结合后路C1, 2经关节螺钉内固定后可视为能满足当前临床需要的一种相对理想的枕颈融合内固定术式。

Objective To explicit the technical parameters in posterior atlanto-occipital transarticular screw fixation; To discuss the clinical significance of craniovertebral junction fixation with transarticular screws. Methods Posterior atlanto-occipital transarticular Kirschner wire implantation was performed under visual control on 30 dried bony specimens that contained complete atlanto-occipital articulations, and cephalocaudal and lateral views were filmed by X-ray, on which the angle and length of the screw trajectory were measured. Results The ideal angle of the atlanto-occipital transarticular screw trajectory was as follows: 53.3°±3.4° upper tilting in sagittal plane and 20.0°±2.6° inside tilting in coronary plane. The length of the trajectory was (29.28±2.46)mm. Conclusion Posterior atlanto-occipital transarticular fixation is clinically feasible; there is a definite direction for implanting the screws and an adjustable range for the allowable length and angle of the trajectory. Posterior atlanto-occipital transarticular fixation can be considered to be an ideal fixation modality for craniovertebral fusion combined with C 1 and C 2 transarticular fixation.