防止股骨颈骨折空心螺钉切出的计算机辅助定量规划方法

The Computer-assisted Method to Prevent Penetration of Cannulated Screws for Femoral Neck Fractures Fixation

目的:建立一种计算机辅助定量手术规划方法,以防止股骨颈骨折术中空心螺钉切出股骨头或股骨颈之外。方法:获取112个正常股骨CT数据,导入软件中进行解剖参数测量,利用三角函数推导数学公式,以精确计算螺钉在股骨颈内的空间分布。利用组内相关系数ICC分析,对测量方法进行观察者之间和观察者内部的一致性信度分析。结果:推导出三个数学公式,能精确计算螺钉在股骨颈内的理想空间分布并防止切出。ICC分析表明,该测量方法具有极好的观察者之间和观察者内部一致性信度。结论:基于CT数据的股骨解剖参数测量方法和数学公式,可为计算机辅助或机器人辅助的精准骨科手术提供可靠的术前和术中手术规划方法。

Objective： To establish a method to quantify the cannulated screws configuration, thus to prevent head/neck penetration during cannulated screws insertion for femoral neck fractures. Methods： CT data of 112 normal femora were analyzed with Mimics and 3-matic software, and parameters of femoral head center/radius, femoral neck isthmus center/radius were measured. A sphere and cylinder were used to approximate the femoral head and neck respectively. With the use of trigonometric function, we tried to deduce mathematical equations which would precisely calculate the ideal location of the cannulated screws without penetrating the femoral head surface and/or femoral neck cortex. The intra-and inter-observer reliability of each measurement were analyzed by Intraclass Correlation Coefficient（ICC）. Results： Three mathematical equations were successfully deduced, and capable of precisely calculating the ideal location of the cannulated screws without penetrating the femoral head surface and/or femoral neck cortex. ICC showed excellent intra-and inter-observer reliability of each measurement. Conclusion： This paper presented a quantified method to prevent femoral head/neck penetration, based on mathematical equations and reliable measurement using CT data of femur. Computer aided or robots aided orthopaedic surgery would benefit from this method to carry out precise and reliable pre-and intra-operative surgical planning.