膝骨关节炎患者股骨后髁软骨磨损差异对人工全膝关节置换术中股骨假体旋转定位的影响

目的通过测量膝骨关节炎患者股骨内、外侧后髁软骨厚度以及后髁角(posterior condylar angle,PCA),探讨其对人工全膝关节置换(total knee arthroplasty,TKA)术中截骨的影响。方法选择2011年5月-12月拟行TKA治疗的53例(60膝)膝骨关节炎患者作为研究对象(骨关节炎组),男12例(14膝),女41例(46膝);年龄57～82岁,平均71.9岁。胫股角为(183.2±2.6)°。以15例(30膝)健康志愿者膝关节作为对照(对照组),男6例,女9例;年龄59～68岁,平均66.3岁。将MRI扫描膝关节获得数据导入Mimics10.01交互式医学影像控制系统,测量内、外侧股骨后髁软骨厚度和包括与不包括后髁软骨时的PCA,进行统计学分析。结果对照组股骨内、外侧后髁软骨厚度分别为(1.85±0.33)mm及(1.92±0.27)mm,包括与不包括后髁软骨时的PCA分别为(5.0±0.9)°和(5.1±0.8)°,差异均无统计学意义(P>0.05)。骨关节炎组股骨内、外侧后髁软骨厚度分别为(0.45±0.40)mm及(1.78±0.51)mm,包括与不包括后髁软骨时的PCA分别为(3.3±1.7)°和(4.8±1.8)°,差异均有统计学意义(P<0.05)。骨关节炎组股骨内、外侧后髁软骨厚度差为(1.33±0.45)mm,与包括与不包括后髁软骨时的PCA角度差(1.5±1.3)°成正相关(r=0.75,P=0.01)。结论膝骨关节炎患者股骨后髁软骨磨损程度存在差异,导致内、外侧后髁软骨厚度和包括与不包括后髁软骨时的PCA存在差异,TKA术中行截骨时,应将股骨后髁软骨厚度差异纳入考虑范围内。

IMPACT OF DIFFERENCES OF POSTERIOR CONDYLE CARTILAGE WEAR ON ROTATIONAL POSITIONING OF FEMORAL PROSTHESIS IN TOTAL KNEE ARTHROPLASTY FOR OSTEOARTHRITIS PATIENTS

Objective To investigate the impact of difference between the medial and lateral posterior condyle cartilage thickness on osteotomy in total knee arthroplasty(TKA) by measuring the thickness of the medial and lateral femur posterior condylar cartilage and the posterior condylar angle(PCA) in osteoarthritis(OA) patients.Methods Between May and December 2011,53 OA patients(60 knees) scheduled for TKA met the inclusion criteria(OA group).There were 12 males(14 knees) and 41 females(46 knees),aged 57-82 years(mean,71.9 years).The tibiofemoral angle was(183.2 ± 2.6)°.Fifteen healthy volunteers(30 knees) were taken as controls(control group);there were 6 males and 9 females,aged 59-68 years(mean,66.3 years).MRI scan data were imported into Mimics10.01 medical image control system to measure the thickness of femur posterior condylar cartilage and the PCA with and without femur posterior condylar cartilage.Results In the control group,the thickness of the medial and lateral femur posterior condylar cartilage was(1.85 ± 0.33) mm and(1.92 ± 0.27) mm respectively,the PCA with and without femur posterior condylar cartilage was(5.0 ± 0.9)° and(5.1 ± 0.8)° respectively,all showing no signi cant differences(P > 0.05).In OA group,the thickness of the medial and lateral femur posterior condylar medial cartilage was(0.45 ± 0.40) mm and(1.78 ± 0.51) mm respectively,the PCA with and without femur posterior condylar cartilage was(3.3 ± 1.7)° and(4.8 ± 1.8)° respectively,all showing signi cant differences(P < 0.05).In OA group,the difference between lateral and medial cartilage thickness was(1.33 ± 0.45) mm,and the difference between PCA with and without femur posterior condylar cartilage was(1.5 ± 1.3)°.There was a positive correlation between the difference of cartilage thickness and the difference of PCA(r=0.75,P=0.01).Conclusion There is signi cant difference between medial and lateral femur posterior condylar cartilage wear,which leads to difference of PCA.The difference will impact knee function and longevity of the prosthesis,so the difference should be considered during osteotomy.