Akagi线作为全膝关节置换胫骨近端假体旋转对线的可靠性研究

Research on the reliability of the Akagi line as a reference axis to guide for rotational alignment of the proximal tibial component in total knee arthroplasty

目的 :在磁共振上测量全膝关节置换胫骨近端假体旋转对线的骨性标志,研究Akagi线作为TKA胫骨近端假体旋转对线的可靠性。方法:2010年1月至2013年12月,80名健康成年人行膝关节磁共振扫描,男35例,女45例,平均年龄(35.4±6.1)岁。在股骨横断面图像上定位股骨外科髁上轴(STEA)并投射到胫骨侧形成STEA’,在胫骨侧横断面图像上定位后交叉韧带止点中点与髌韧带内侧缘连线(Akagi线)及其垂线(AK),后交叉韧带止点中点与髌韧带中内1/3连线及其垂线(AP),比较AK、AP相对于STEA’的角度。结果:AK与STEA’的夹角为(0.59±2.07)°,与STEA’的平行线相比较,差异无统计学意义(t=-2.54,P=0.13);AP与STEA’夹角为(3.21±2.04)°,与STEA’的平行线相比较,差异有统计学意义(t=14.05,P<0.05)。AK与AP比较,两线间走行方向差异较大(t=-11.68,P<0.05)。结论:Akagi线作为全膝关节置换胫骨近端假体旋转对线的可靠性高。

Objective：To study on the reliability of the Akagi line as a reference axis to guide for rotational alignment of the proximal tibial component in total knee arthroplasty（TKA）,the rotational alignment reference bony landmarks of the proximal tibial component on magnetic resonance image（MRI） were measured. Methods：From January 2010 to December 2013,80 normal knees of Chinese volunteers including 35 males and 45 females with an average age of（35.4±6.1） years were reviewed.The images of the knees were obtained by MRI. The surgical epicondylar axis（STEA） was identified in the femoral transverse sections and then was projected to the side of tibia,forming the SETA’. A line connecting the medial border of the patellar tendon and the middle of the posterior cruciate ligament insertion（Akagi line） and its vertical line（AK）,as well as a line connecting the medial 1 / 3 of the patellar tendon and the middle of the posterior cruciate ligament insertion and its vertical line（AP）,were identified in the tibial transverse sections. The angles were measured between the AK,AP and STEA’. Results：The angle between AK and STEA’ was（0.59 ± 2.07）°,and there was no significant difference between the two lines（t=-2.54,P=0.13）.The mean angle between AP and STEA’ was（3.21±2.04）°,and there was a significant difference between the two lines（t=14.05,P〈0.05）. There was a significant difference between the AK and AP（t=-11.68,P〈0.05）. Conclusion：The reliability of the Akagi line as a reference axis to guide for rotational alignment of the proximal tibial component in TKA is good.