Wiberg分型对保留髌骨TKA术后髌骨轨迹及功能的影响

Effect of Wiberg Patella Classification on Patellar Tracjectory and Function after Total Knee Arthroplasty with Patella Preservation

目的研究全膝关节置换术(total knee arthroplasty,TKA)对髌骨形态、术后轨迹及术后功能的影响。方法选取2016年1月到2017年1月因膝关节骨关节炎行TKA的患者共76例(81膝),男21例(22膝),女55例(59膝);年龄53~77岁,平均(66.19±6.83)岁。于屈膝45°、投射角度30°的数字化X线成像系统上拍摄膝关节髌骨轴位片,使用Wiberg标准评估髌骨分型并测量髌骨倾斜角、髌股指数、髌股适合角。术中保留髌骨,对髌骨周边骨赘进行清除,保持正常的髌骨解剖形态。术前Wiberg分型Ⅰ型18膝,Ⅱ型49膝,Ⅲ型14膝。比较不同Wiberg髌骨分型手术前后的影像学指标、美国特种外科医院(the hospital special surgery,HSS)功能评分、髌骨评分、上下楼评分、膝前痛视觉模拟评分(visual analogue scale,VAS)。结果术后患者均获随访,随访时间均两年以上,平均随访时间(25.16±6.24)个月。髌骨倾斜角由术前(-10.04±4.74)°减小为术后(-7.54±4.61)°,差异具有统计学意义(P=0.000);髌股指数由术前(1.50±0.54)减小为术后(1.17±0.59),差异具有统计学意义(P=0.047)。术前WibergⅠ型髌骨倾斜角(-11.05±5.6)°,Ⅱ型(-8.74±5.6)°,Ⅲ型(-13.22±3.72)°,差异有统计学意义(P=0.013);术前WibergⅠ型髌骨髌股指数(1.53±0.53),Ⅱ型(1.35±0.47),Ⅲ型(1.95±0.58),差异有统计学意义(P=0.004)。WibergⅡ型的患者术前髌骨倾斜角及髌股指数较其他两型要小。术前不同Wiberg髌骨分型的髌股适合角度差异有统计学意义(P=0.006)。不同Wiberg分型的患者术后髌骨倾斜角(P=0.117)、髌股指数(P=0.058)、髌股适合角度(P=0.572),差异无统计学意义(P>0.05)。不同Wiberg分型的患者术后HSS评分(P=0.572)、美国膝关节协会评分(knee society score,KSS)(P=0.657)、KSS功能评分(P=0.066)、髌骨评分(P=0.102)、上下楼评分(P=0.080)、VAS评分(P=0.332)差异无统计学意义。结论全膝关节置换术中,通过髌骨成形及外侧支持带松解可达到良好的术后髌骨轨迹及临床疗效。Wiberg髌骨形态对保留髌骨型全膝关节置换术后功能无明显影响。

Objective To study the patellar morphology,postoperative trajectory and function of total knee arthroplasty(TKA).Methods From January 2016 to January 2017,76 patients(81 knees)underwent total knee arthroplasty for osteoarthritis of the knee.The patients aged 53~77 years,with an average age of(66.19±6.83)years,including 21 males(22 knees)and 55 females(59 knees).Axial patellar films were taken on a digital X-ray imaging system with 45 degrees flexion and 30 degrees projection angle.Patellar classification was assessed by Wiberg criteria and patellofemoral inclination angle,patellofemoral index and patellofemoral fit angle were measured.During the operation,the patella was preserved,osteophytes around the patella were removed,and normal patellar anatomy was maintained.Preoperative Wiberg typeⅠpatella was found in 18 case of knees,typeⅡin 49 case of knees and typeⅢin 14 case of knees.The imaging indexes and HSS functional score(HSS),KSS functional score(KSS)and Fellar Patellar Score(Fellar Patellar Score),upstairs and downstairs score and VAS score of anterior knee pain were compared before and after operation for different Wiberg patellar classification.Results The follow-up time was more than two years,and the average follow-up time was(25.16±6.24)months.Patellofemoral index decreased from preoperative(-10.04±4.74)degrees to postoperative(-7.54±4.61)degrees.The difference was statistically significant(P=0.000).Patellofemoral index decreased from preoperative(1.50±0.54)to postoperative(1.17±0.59).The difference was statistically significant(P=0.047).Preoperative tilt angle of patella of Wiberg typeⅠ(-11.05±5.6)degrees,typeⅡ(-8.74±5.6)degrees,typeⅢ(-13.22±3.72)degrees had significant difference(P=0.013)before operation.Patellofemoral index of Wiberg typeⅠ(1.53±0.53),typeⅡ(1.35±0.47),and type typeⅢ(1.95±0.58)had significant difference(P=0.004).The preoperative patellar tilt angle and patellofemoral index of WibergⅡpatients were smaller than those of the other two types.There were significant differences in patellofemoral fitness angles among different Wiberg patellar types before operation.(P=0.006).There was no significant difference in patellar tilt(P=0.117),patellofemoral index(P=0.058)and suitable angle(P=0.572)among different Wiberg classification patients(P>0.05).There were no significant differences in HSS score(P=0.572),KSS clinical score(P=0.657),KSS functional score(P=0.066),patella score(P=0.102),upstairs and downstairs score(P=0.080),VAS score(P=0.332)among the patients with different Wiberg classification.Conclusion In total knee arthroplasty,good patellar trajectory and clinical effect can be achieved by patelloplasty and lateral retinaculum release.Wiberg's patellar morphology has no significant effect on the function after total knee arthroplasty with patellar preservation.