成人继发性膝外翻畸形股骨远端的数字化测量与分析

Digital measurement and analysis of the distal femur in adults with secondary knee valgus deformity

背景:膝外翻畸形一般需要膝关节周围截骨或全膝关节置换来矫形。膝关节周围截骨时需要三维立体矫正,人工全膝关节置换选用假体与膝关节相匹配的程度明显影响置换后长期效果,股骨髁截骨矫形需要股骨髁数据支持。目前国内使用率较高的仍然是依据西方人数据设计的假体系统,应用于国人往往达不到最好匹配。目的:探讨股骨髁解剖形态学异常,为膝外翻畸形的全膝关节置换或截骨术提供解剖学数据。方法:对41例(53膝)成人膝外翻畸形患者的膝关节进行CT扫描,图像导入Mimics 17.0软件建立数字化三维模型,测量相关解剖学参数,分析其分布规律与相关关系。将膝关节相关参数与单膝畸形患者的健侧正常膝(对照组29膝)进行比较。结果与结论:(1)与对照组比较,外翻组股骨机械轴和通髁轴的夹角无显著变化(P>0.05);股骨机械轴和股骨远端关节面的夹角、通髁轴与股骨髁远端关节面切线的夹角、通髁轴与股骨髁后方关节面切线的夹角均显著增加(P<0.05)。(2)从股骨髁表面轮廓测量结果可以看出,外翻组股骨外髁数据明显低于对照组(P<0.05),两组股骨内髁数据相比差异无显著性意义(P>0.05)。(3)外翻组股骨髁后部圆心和股骨髁通髁线距离明显低于对照组(P<0.05)。(4)结果表明,成人继发性膝外翻畸形的股骨外髁形态学变化较显著,股骨内髁形态学变化不明显。将股骨髁通髁轴做为成人继发性膝外翻畸形全膝关节置换的参照,获取的数据有助于术中定位,提高治疗效果。

BACKGROUND:The surgical method for knee valgus deformity is osteotomy around the knee joint or total knee arthroplasty.Osteotomy around the knee joint needs three-dimensional shaping.The type of artificial total knee arthroplasty prosthesis and the degree of matching with the knee joint affect the long-term effect after arthroplasty.Femoral condyle osteotomy shaping usually requires the support of femoral condyle data.Nowadays,prosthesis systems designed by westerners have a relatively high usage rate in China,but cannot achieve the best results in the Chinese.OBJECTIVE:To explore the anatomical abnormalities of the femoral condyle,and provide anatomical data for total knee arthroplasty or osteotomy of knee valgus deformity.METHODS:Totally 41 adult patients(53 knees)with knee valgus deformity were detected with CT scan.The obtained images were imported into Mimics17.0 software,and digital three-dimensional model was established.The anatomical parameters were measured,and the distribution and correlation were analyzed.The knee joint parameters between knee valgus deformity patients and healthy normal knee in single deformity patients(control group,n=29)were compared.RESULTS AND CONCLUSION:(1)Compared with the control group,epicondylar angle was not significantly different in the valgus group(P>0.05).Medial mechanical femoral angle,distal condylar angle,and poster condylar angle were significantly increased in the valgus group(P<0.05).(2)Measurement results of the surface profile of the femoral condyle showed that femoral condyle data were significantly lower in the valgus group than that in the control group(P<0.05).No significant difference in femoral medial condyle data was found between the valgus and control groups(P>0.05).(3)The distance between the center of the femoral condyle and the condyle line of the femoral condyle was significantly lower in the valgus group than that in the control group(P<0.05).(4)These findings indicate that the morphological changes of the femoral lateral condyle of adult secondary knee valgus deformity are more significant,but the morphological changes of the femoral medial condyle are not obvious.The femoral condyle axis is used as a reference for adult secondary valgus total knee arthroplasty.The data obtained can help intraoperative positioning and improve the treatment effect.