微创膝关节单髁置换术股骨髓内定位与髓外定位假体位置的影像学比较

[目的]通过对膝关节单髁置换术股骨假体的力线测量,评价股骨髓外定位法指导假体放置的有效性.[方法]回顾性分析2007年5月～2010年5月采用微创单髁置换术治疗膝关节内侧间室骨性关节炎的患者73例(80膝),其中股骨髓内定位组(intramedullary alignment guide,IM) 54例(56膝),男23例(23膝),女31例(33膝)；股骨髓外定位组(extramedullary alignment guide,EM)19例(24膝),男9例(10膝),女10例(14膝).测量术后即刻股骨假体内翻/外翻和屈/伸力线.[结果]IM组股骨假体内翻/外翻力线为0.59°内翻±3.98°,EM组股骨假体力线平均为0.81°外翻±3.30°,P=0.235 2.IM组股骨假体屈/伸力线为0.70°伸直±3.89°,EM组股骨假体力线为1.12°伸直±3.43°,P=0.564 3.[结论]微创膝关节单髁置换术股骨髓内定位可取得与髓外定位法相同优良的股骨假体力线.

Accuracy of extramedullary or intramedullary alignment guide for femoral component placement in minimally invasive unicondylar knee arthroplasty

[Objective]To measure the femoral component alignment in order to evaluate the validity of extramedullary femoral alignment guide.[Methods]Between May 2007 and May 2010,73 consecutive patients(80 knees)with unicompartmental knee osteoarthritis were treated with minimally invasive unicondylar knee arthroplasty(MI-UKA).Intramedullary alignment guide(IM) group had 23 males(23 knees) and 31 females(33 knees).Extramedullary alignment guide(EM) group had 9 males(10 knees) and 10 females(14 knees).The postoperative femoral component alignments(valgus/varus,flexion/extension) were measured and compared.[Results]The mean valgus/varus femoral component alignment was 0.59°varus±3.98° in IM group,and 0.81°valgus±3.30° in EM group(P=0.2352).The mean flexion/extension femoral component alignment was 0.70°extension±3.89° in IM group,and 1.12°extension± 3.43° in EM group(P=0.564 3).[Conclusion]Minimally invasive unicondylar knee arthroplasty via EM guide is an effective alternative for the treatment of medial compartmental knee osteoarthritis.It can obtain as excellent femoral component alignment as IM guide can.