3D打印截骨导板辅助全膝关节置换术中股骨切迹发生原因的初步研究

Analysis of anterior femoral notching in total knee arthroplasty using 3D printing technique

背景:股骨远端前弓对全膝关节置换术中股骨侧假体安放位置及前侧皮质切迹有较大影响。目的:初步研究3D打印辅助全膝关节置换术出现股骨切迹的原因。方法:选取2017年1月至2018年1月膝关节骨关节炎拟行单侧全膝关节置换术患者131例,其中男性25例,女性106例,年龄49~84岁,平均(66.2±8.0)岁。术前行双下肢全长CT扫描获得股骨的3D图像。应用Mimics 17.0软件测量每个股骨远端矢状位前偏角度(distal femoral sagittal anterior angle,DFSAA)。按照DFSAA大小分成A、B两组,A组DFSAA>3°,39例,B组≤3°,92例;设计并制作3D打印截骨导板,辅助全膝关节置换术。术中观察股骨切迹情况,术后行膝关节标准正侧位片,记录股骨切迹发生例数。术后1年随访,观察两组膝关节置换术后功能(HSS评分)。结果:患者平均DFSAA为2.51°±1.50°;男性平均2.58°±1.59°,女性平均2.50°±1.49°,男性和女性比较,差异无统计学意义(P=0.389);A组发生股骨切迹6例,均为GujarathiⅠ型,发生率为15.4%;B组没有发生股骨切迹。术后A、B两组HSS评分分别为(85.5±7.6)分和(83.7±7.4)分,差异无统计学意义(P>0.05)。结论:当DFSAA>3°时,使用3D打印截骨导板辅助截骨,股骨切迹发生率显著增加。对于DFSAA>3°的患者,推荐参考解剖轴线截骨,或改用传统股骨髓内杆定位方法。

Background:The distal femoral arch has a significant influence on the placement of femoral prosthesis and anterior femoral notching in total knee arthroplasty.Objective:To preliminarily analyze the cause of anterior femoral notching in total knee arthroplasty using 3 D printing technique.Methods:A total of 131 patients including 25 men and 106 women,with the mean age of(66.2±8.0)years(range:49-84 years)who underwent unilateral total knee arthroplasty for primary knee osteoarthritis between January 2017 and January 2018 were selected.Prior to the surgery,the 3 D images of femurs were acquired by CT full-length scan of bilateral lower limbs,then the distal femoral sagittal anterior angle(DFSAA)was measured and analyzed with Mimics 17.0 software,and all patients were divided into two groups according to the value of DFSAA:Group A with DFSAA>3°(n=39)and Group B with DFSAA≤3°(n=92).3 D printing osteotomy bloc was designed by the SIEMENS NX 9.0 software and applied in TKA.During the surgery,the notching was observed.After the surgery,standard anteroposterior and lateral X-ray of the knee were taken,which were used to record the sum of femoral notch.1 year after the surgery,the function of the knee of all patients were assessed by HSS scores.Results:The DFSAA was 2.51°±1.50°on average,2.58°±1.59°in men and 2.50°±1.49°in women,and the difference between men and women was not statistically significant(P=0.389).The notching happened to 6 patients in group A and all of them were GujarathiⅠwith the incidence of 15.4%.No notching happened in group B.HSS scores after the surgery were 85.5±7.6 and 83.7±7.4 in group A and group B respectively,and no significant difference was found for HSS between the two groups.Conclusions:When DFSAA is more than 3°,the incidence of anterior femoral notching in TKA using 3 D printing technique increases obviously.For these patients with DFSAA more than 3°,osteotomy with reference to anatomic-axis in 3 D printing design or femoral intramedullary rod positioning method is recommended.