计算机导航辅助下与传统全膝关节置换术后下肢力线和假体位置的比较

A comparison of the mechanical axis and alignment of component between conventional total knee arthroplasty and total knee arthroplasty under computer-assisted navigation

目的比较计算机导航辅助下和传统方法进行全膝关节置换（TKA）术后膝关节下．肢力线和假体位置。方法对2007年5门至2009年12月收治的60例膝骨关节炎患者进行前瞻性研究，随机分为计算机导航组（导航组）和传统方法组（传统组），每组30例。导航组：男11例，女19例；平均年龄（69．2±8．3）岁；术前忠行下肢力线平均偏差9．4°±5．3°；膝关节骨关节炎分级：Ⅲ级12例，Ⅳ级18例。传统组：男17例，女13例；平均年龄（71．9±8．1）岁；术前患行下肢力线平均偏差8．9°±4．8°。膝关节骨关肖炎分级：Ⅲ级17例，Ⅳ级13例。均采用同种产品的TKA，所有手术均由同一组医生完成。比较两组患者膝外翻角、冠面和矢状面的假体组件角度和手术时川。结果导航组髋-膝-踝角平均偏差角度（0．7°±0．2°）小于常规组（1．2°±0．3°），差异有统计“挲意义（t=3．972，P=0．000）。导航组额面股骨部分角平均偏差角度（1．5°±0．4°）小于传统组（2．1°±0．5°），差异有统计学意义（t=2．433，P=0．017）。导航组额面胫骨部分角（1．4°±0．5°）平均偏差角度小于传统组（1．5°±0．6°），差异无统计学意义（t=0．326，P=0．116）。导航组侧面股骨部分角（7．3°±0．4°）和侧面胫骨部分角（2．5°±0．2°）平均偏差角度均小于传统组（9．5°±0．4°、4．5°±0．6°），差异均有统计学意义（P〈0．05）。导航组平均手术时间比传统组延长15-28min，差异有统计学意义（t=2．553，P=0．008）。结论计算机导航辅助下TKA与传统办法相比，下肢力线和假体组件的位置史准确。

Objective To compare the mechanical axis and alignment of component between convent ional total knee arthroplasly （TKA） and TKA under computer-assisted navigation. Methods From May 2007 to December 2009, 60 patients with knee osteoarthritis were assigned randomly to receive conventional TKA and computer-assisted navigation TKA with the same type of implant for eaeh knee. In navigation group （group A）, there were 11 men and 19 women, with an average age of 69.2 ± 8.3 years. The mean preoperative aligmnent deviation was 9.4°± 5.3° . The knee osteoarthritis was rated as grade Ⅲ in 12 cases and grade 1V in 18 cases. In conventional group （group B）, there were 17 men and 13 women, with an average age of 71.9 ±8. 1 years. The mean preoperative alignment deviation was 8.9°±4.8° . The knee osteoarthritis was rated as grade as grade Ⅲ in 17 cases and grade Ⅳ in 13 cases. Alignment of the leg and orientation of components were evaluated on standard pre- and post-operative full-length weight-bearing radiographs and lateral X-rays with lvgard to the valgus angle and the coronal and sagittal component angles. Results The mean deviation in hip-knee-ankle angle in group A （0. 7°± 0.2°） was significantly smaller than that in group B （ 1.2°± 0. 3°） （ t = 3. 972, P = 0. 000） . The mean postoperative deviation in frontal femoral eomponent angle in group A （1.5°±0.4°） was significantly smaller than that in group B （2.1 °±0.5°） （t=2.433, P = 0. 017） . The mean deviation in frnntal tibial component angle in group A （2. 1°± 0.5°） was insignifi- cantly smaller than that in group B （ 1.5°± 0.6°） （ t = 0. 326, P = O. 116） . The mean deviations in lateral femoral component and lateral tibia] component angles in group A （7.3°± 0. 4° and 2.5°± 0.2°） were signifi- cantly smaller than those in group B （9.5°±0.4° and 4.5°±0.6°） （ P 〈 0.05）. The operating time in group A was 15 to 28 minutes longer than in group B（ t =2. 553, P =0. 008） . Conclusion Cmnputer-assisted navigation system used in TKA can resuh in a better correction of alignment of the leg and better orientation of the components than does conventional TKA.