全髋关节置换非骨水泥型股骨柄假体髓腔准备的精确性研究

目的观察非骨水泥型股骨柄假体在股骨近端髓腔中与骨组织的接触情况及使用机器人辅助手术与传统手术结果的比较。方法在10具新鲜成人尸体股骨标本上,分别采用传统手术及机器人辅助手术行股骨近端髓腔准备后植入近端固定的非骨水泥型股骨柄假体(Osteolock)。经一系列处理后,用钻石刀按层厚3mm行硬组织切片,摄片,扫描输入计算机并用特殊软件(IDL)分析假体近端情况。分别测量假体与骨组织间缝隙的宽度以及假体表面缝隙的长度及其所占假体周径的百分比,假体表面与骨直接接触所占的百分比。结果机器人辅助手术组(实验组)平均假体近端表面与骨直接接触率达93.2%(87.6%～99.7%),假体表面与骨组织间存在由手术造成的缝隙率仅为2.9%(0.3%～7.8%),最大缝隙宽度小于1mm;而传统手术组(对照组)骨直接接触率为60.1%(49.2%～70.4%),由手术造成的缝隙率达32.8%(25.1%～39.9%),最大缝隙宽度达3mm。采用机器人辅助手术可使假体表面与骨直接接触率较传统手术增加约33%,手术误差造成的缝隙率仅为传统手术的9%,最大缝隙宽度为传统手术的26%。结论机器人辅助手术可使股骨近端髓腔与非骨水泥型股骨柄的直接接触率明显提高(P<0.001)。

A study of the accuracy for femoral components preparation in cementless total hip arthroplasty

Objective To observe the accuracy for femoral preparation and the situation of the c e-mentless prosthesis in femoral cavity,and compare the results between t he computer aided surgical planning robotics group(CASPAR)and the conventional group.Methods Ten femoral components were implant ed either manually or by CASPAR in cadaver femurs.The specimens were sectio ned into slices of 3mm thick-ness.Micro-radiograms were adopte d for every slice,and the images were transmitted to a computer for analysis with special dedicated software(IDL).The gaps between component and bone,the medullary cavities,the direct bone contact areas of the i mplant surface,the width of gap and t he percentage of gap and bone contact area were measured and recorded in every slice.Results In the proximal implant coated with HA of the CASPAR group,the average percen tage of bone contact reached up to 93.2%with the range from 87.6%to 99.7%;the average gap percentage was 2.9%with the range from 0.3%to 7.8%;the maximum gap width was 0.81mm and the average gap w idth was only 0.20mm.While in the con ventional group,the av-erage percentage of bone contact was60.1%with the range from 49.2%to 70.4%;the average gap per-centage was 32.8%with the range from25.1%to 39.9%;the maximum gap width was 2.97mm and the average gap width was 0.77mm;in the c omparison of the two groups,the average gap percentage around implant in the CASPAR group was only 9%of that in the manual group,the maximum and average gap width were only about 26%of that in the manual group;on the other hand,the CASPA R group showed 33%higher bone contact than the manual group.Conclusion With the use of robotic-assisted system,a significant progress can be achieved for femoral components preparation in total hip arthroplasty.