股骨前轴作为全膝关节置换术中旋转对线标准的磁共振测量实验

MRI research of anterior femoral axis as standard of femoral rotation alignment in total knee arthro-plasty

目的 :通过正常成人和膝关节骨性关节炎患者膝关节磁共振研究,确立股骨前轴在全膝关节置换手术中作为股骨旋转对线标志的重要作用。方法:本研究对60侧正常膝关节(A组),骨性关节炎中40侧轻度内翻畸形膝关节(B组)及20侧重度内翻畸形膝关节(C组)行磁共振(MR)扫描,测量三组后髁轴、Whiteside’s轴、股骨前轴相对于外科经股骨髁上轴及临床经股骨髁上轴旋转的角度,对各个角度做三组之间的比较研究。结果:股骨后髁角(PCA)为-(3.2±1.6)°、髁转角(CTA)为-(7.0±1.7)°、Whiteside’s轴相对于外科经股骨髁上轴旋转的角度(WSA)为-(87.7±3.6)°、Whiteside’s轴相对于外科经股骨髁上轴旋转的角度(WCA)为-(91.4±3.6)°、股骨前轴相对于外科经股骨髁上轴旋转的角度(AFSA)为-(9.0±2.2)°、股骨前轴相对于临床经股骨髁上轴旋转的(AFCA)为-(12.8±2.4)°,LSD-t检验提示PCA及CTA在A组与C组之间差异有统计学意义(P分别为0.011和0.041),余组间差异无统计学意义(P>0.05)。WSA及WCA在各组之间差异均无统计学意义(P>0.05)。AFSA及AFCA在各组之间差异均无统计学意义(P>0.05)。结论:股骨前轴较股骨后髁轴、Whiteside’s轴受骨性关节炎影响小,可以参照此轴放置股骨假体。

Objective： Through magnetic resonance research （MRI） in knees of normal adults and osteoar- thritis patients, to establish the important role of anterior femoral axis as femoral rotation alignment marks in total knee arthroplasty. Methods： 60 normal knees, 40 knees of mild varus deformity （7° -20°） and 20 knees of severe varus deformity （〉20°） were scanned with MRI. On the three-dimensional images measured by MRI, the angles between the Whiteside line （WL）, the posterior condylar axis （PCA）, the anterior femoral axis （AFA） and the surgical transepicondylar axis （STEA）, the clinical transepicondylar axis （CTEA）, were located. Then, the comparative study were done between three groups. Results： The posterior condylar angle （PCA） was -（3.2 ±1.6）° of three groups, the condlar twist angle （CTA） was -（7.0 ± 1.7）°, the angle between Whiteside line and STEA （WSA） was -（87.7 ± 3.6）°, The angle between Whiteside line and CTEA （WCA） was -（91.4 ± 3.6）°, the angle between TL and CTEA （AFSA） for -（9.0 ± 2.2）°, and the angle between AFA and STEA （AFCA） was -（12.8 ± 2.4）°. LSD - t test showed statistical differences of PCA and CTA in normal knee joint group and severe varus deformity group （P were 0.011 and 0.041 respectively）, no significant difference between the other two groups. WSA and WCA in each group were no significant statistical difference. AFSA and AFCA in each group were no significant statistical difference. Conclusion： Comparing to WL and PCA, the AFA wasn＇t affected by osteoarthritis, which could be refer to place femoral prosthesis in TKA.