膝关节置换术髓外定位系统中三种胫骨远端解剖标志物的对比研究

Comparison of three anatomical structures as a distal landmark for extramedullary tibial alignment in total knee arthroplasty

目的 比较足背动脉、（足母）长伸肌腱和趾长伸肌腱作为膝关节置换术胫骨髓外定位系统中胫骨远端解剖标志物的准确性. 方法 以2012年8月至2014年8月期间56例行膝关节置换术患者的56侧踝关节为研究对象,用彩色多普勒超声分别测量足背动脉中点、（足母）长伸肌腱外侧缘和趾长伸肌腱内侧缘在踝关节屈曲90°中立位、屈曲90°外旋30°及屈曲90°内旋30°时至踝关节中点的距离,并采用重复测量的方差分析及单因素方差分析检测其差异. 结果 3种解剖标志物、3种不同体位及两者交互作用的效应均显著,差异有统计学意义（P＜0.05）.在3种解剖标志物中,足背动脉离踝关节中点最近,位于踝关节中点外侧（0.20 ±0.21） cm;其次为（足母）长伸肌腱,位于踝关节中点内侧（0.46 ±0.36） cm;最远的是趾长伸肌腱,位于踝关节外侧（0.63±0.30）cm.同一种解剖标志物在不同踝关节体位下与踝关节中点距离两两之间比较差异均有统计学意义（P＜0.05）.在同一种踝关节体位下3种解剖标志物与踝关节中点的距离两两之间比较差异均有统计学意义（P＜0.05）,在3种踝关节体位下足背动脉都最接近踝关节中点. 结论 足背动脉至踝关节中点的距离在踝关节不同体位下均较（足母）长伸肌腱及趾长伸肌腱近,可以作为膝关节置换术髓外定位系统中胫骨远端的可靠解剖标志物.

Objective To compare dorsal pedis artery,extensor hallucis longus tendon and extensor digitorum longus tendon as a distal landmark in terms of accuracy of extramedullary tibial alignment in total knee arthroplasty.Methods Color Doppler ultrasonography was used in 56 ankles of 56 patients undergoing total knee arthroplasty to locate the dorsal pedis artery,the extensor hallucis longus tendon and the extensor digitorum longus tendon at the ankle joint at 3 different positions （90° dorsal flexion with neutral rotation,90° dorsal flexion with 30° external rotation and 90° dorsal flexion with 30° internal rotation）.The distances between the ankle centre and 3 landmarks at 3 positions were measured and compared by analysis of variance with repeated measurements and one way analysis of variance.Results Analyses of variance with repeated measurements showed significant differences between the distances to the ankle center of the 3 landmarks at tbe 3 positions （P 〈 0.05）.The dorsal pedis artery lay the closest to the ankle center （0.20 ± 0.21 cm lateral）,followed by the extensor hallucis longus tendon （0.46 ± 0.36 cm medial） and the extensor digitorum longus tendon （0.63 ± 0.30 cm lateral）.One way analysis of variance showed significant differences in distance from each landmark to the ankle center at different ankle positions （P 〈 0.05）.There were significant differences between 3 anatomical landmarks in distance to the ankle center at the same ankle position （P 〈 0.05）.The dorsal pedis artery was the closest to the ankle center at all ankle positions.Conclusion Since the dorsal pedis artery lies closer to the ankle center than the extensor hallucis longus tendon and the extensor digitorum longus tendon at different ankle positions,it can be a reliable distal landmark for extramedullary tibial alignment in total knee arthroplasty.