旋转平台与固定平台全膝关节置换术的对比研究及髌骨置换与否对疗效的影响

Comparative study of rotating platform and fixed bearing total knee arthroplasty and whether Patella resurfacing is useful

目的评估旋转平台和固定平台假体全膝关节置换(TKA)两型假体间的疗效有无差异及髌骨置换与否对疗效的影响。方法选取同一医师施行的78侧初次TKA进行回顾。术前诊断包括骨关节炎、类风湿性关节炎等。施行固定平台TKA手术的患者共30侧,14侧置换髌骨;施行旋转平台TKA手术的共48侧,36侧置换髌骨。术前和术后随访行膝HSS评分、测量关节伸直角度和屈曲角度,以比较两型假体TKA疗效;比较髌骨置换组与未置换组TKA疗效;在髌骨置换组与未置换组中,分别比较固定平台TKA和旋转平台TKA的疗效。结果成功随访76侧,平均25.2个月。旋转平台组术后HSS评分、伸直角度与固定平台组间的差异无统计学意义,前者术后的屈曲角度(112.0±11.5)°优于固定平台组间的差异有统计学意义(t=3.270,P<0.01)。髌骨未置换组术后HSS评分、伸直角度与髌骨置换组(102.5±15.1)°组间差异有统计学意义(t=2.469,P<0.05;t=3.747,P<0.01),术后屈曲角度与后者间的差别无统计学意义。髌骨未置换组中,旋转平台TKA与固定平台TKA的术后HSS评分、屈曲角度无差异,伸直角度差别无临床意义。髌骨置换组中,旋转平台TKA术后HSS评分、伸直角度与固定平台TKA间的差异无统计学意义,前者术后的屈曲角度(112.9±13.0)°与后者术后的屈曲角度(96.7±18.4)°比较差异有统计学意义(t=2.838,P<0.05)。结论旋转平台假体与固定平台假体TKA术后总体疗效相似,旋转平台假体能够更好地改善关节屈曲角度;置换髌骨并不能更好地改善膝关节功能。

Objective Cases of rotating platform total knee arthroplasty（TKA） and fixed bearing TKA were followed up to evaluate whether the outcomes between the two types of prosthesis were different or not,and to assess if resurfacing and not resurfacing patella would influence the outcome.Methods 78 primary TKAs performed by the same surgeon were followed up,including 30 fixed bearing TKAs with 14 patellae resurfaced and 48 rotating platform TKAs with 36 patellae resurfaced.The average age of the cases was 65.5 years.Preoperative diagnoses included osteoarthritis,rheumatoide arthritis etc.Preoperative and postoperative knee functions were scored by the HSS standard.Preoperative and postoperative extension angle and flexion angle of the knees were also measured respectively in order to compare the outcomes between the two different types of prosthesis,as well as the outcomes between the TKA groups with and without patella resurfacing.In the group of patella resurfacing and the group of patella not resurfacing,the outcomes between rotating platform TKA and fixed bearing TKA were compared respectively.Results 76 Knees were successfully followed up with an average duration of 25.2 months.With regard to postoperative HSS score and extension angle,there were no differences between the group of rotating platform and the group of fixed bearing.The group of rotating platform had better postoperative flexion angle（112.0 ± 11.5） ° than that of fixed bearing group（102.0 ± 15.1） °,（t = 3.270,P 0.01）.The group without patella resurfacing was superior to the group with patella resurfacing for postoperative HSS score（90.1 ± 6.8,85.2 ± 10.7,t = 2.469,P 0.05） and extension angle（t = 3.747,P 0.01） while there was no statistical difference with regard to postoperative flexion angle.In the group without patella resurfacing,there was no significant difference for HSS score and flexion angle between rotating platform TKA and fixed bearing TKA,and the difference of extension angle between the two types of prosthesis had no clinical significance.In the group with patella resurfacing,rotating platform TKA had better postoperative flexion angle than fixed bearing TKA（112.9° ± 13.0°,96.7° ± 18.4°,t = 2.838,P 0.05） while there was no difference as regard to HSS score and extension angle.Conclusions The overall outcomes of rotating platform TKA and fixed bearing TKA are similar.Rotating platform TKA can improve postoperative flexion angle better than fixed bearing TKA.Patella resurfacing is not superior to patella not resurfacing as regard to improving knee function.