Effect Of Patellofemoral Degeneration On The Curative Effect Of TKA With Patella Retention

ObjectiveThe patellofemoral arthritis was graded according to the severity of patellofemoral arthritis,and the effect of the severity of patellofemoral arthritis on total knee arthroplasty(TKA)with patella retention was compared to provide a basis for clinical treatment.MethodsPatients who underwent total knee arthroplasty in the first affiliated hospital of zhengzhou university from April 2017 to December 2018 were collected,and a total of 106 patients were included in the study.All patients underwent primary unilateral replacement with the same brand of prosthetics(Depuy of America)and were operated by the same primary surgeon.During the operation,the patella of all the patients was not replaced,Patelloplasty and patella denervation were performed.Using the Lwano classification system,the patients were divided into mild group(stage ???)and severe group(stage ???)according to the severity of patellofemoral arthritis.There were 53 patients in the mild group,including 27 on the left and 26 on the right,22 males and 31 females,age ranging fron 54 to 79 years,and average of age were 65.34±7.62 years old,BMI ranging fron 20.28 to 35.52 kg/m2,and average of BMI were 26.74±2.45 kg/m2.There were 53 patients In the severe group,including 28 on the left and 25 on the right,20 male and 33 female,aged ranging from 55 to 78 years,average of age were 66.28±6.37 years,and BMI ranging from 22.15 to 32.54 kg/m2,average of BMI were 25.48±4.29 kg/m2.The two groups of patients were followed up respectively,and the data of clinical function score and radiographic outcomes were collected in the 3 months,6 months,1 year after the operation.The American knee society score,the Feller score and the pain score of knee were used to evaluate the prognosis of clinical function.The radiographic prognosis was evaluated by patellar tilt angle,congruence angle,lateral patellar displacement and patellar ligament ratio.This study was designed as a prospective study,a=0.05 and the Power1-?=90%was used to estimate the sample size before the study,SPSS 21.0 software was used to analyze the data.After the normality test,the t test or mann-whitney rank sum test were used for the measurement data.The counting data were tested by chi-square test,and P<0.05 was statistically significant.ResultsThe two groups of patients were followed up for at least 1 years.7 patients were lost to follow-up,and 1 patient had postoperative incision fat liquefaction,which was healed affer debridement.One patient suffered from periprosthesis fracture due to accidental fall one year after surgery,and the prosthesis healed well without loosening after internal fixation.One patient had persistent knee pain after surgery.There were no infected revision patients.There was no significant difference in age,gender,BMI,operation time and follow-up time between the two groups(P>0.05).There were statistically significant differences in knee clinical score,by patellar tilt angle,congruence angle,lateral patellar displacement between the mild and severe groups before surgery(P<0.05).Clinical scores,knee function scores,Feller scores,pain scores of knee,patellar tilt angle,congruence angle,lateral patellar displacement and patellar ligament ratio of the mild group and the severe group at 3 months,6 months and 1 years after surgery showed no statistically significant differences(P>0.05).Conclusion1.The postoperative clinical function and radiographic evaluation in the severe and mild patellofemoral arthritis groups were significantly improved compared with the preoperative results,indicating that patients with severe patellofemoral arthritis underwent TKA with patelloplasty and dennerized of retented patellar will not affected the clinical efficacy.2.There was no significant difference in postoperative clinical function and radiographic evaluation between the two groups with severe and mild patellofemoral arthritis,indicating that patients with severe patellofemoral arthritis could still not replace the patella in TKA,and the same excellent effect as mild patellofemoral arthritis could be obtained through patelloplasty and dennerization3.There was no significant difference in the effect of severe and mild patellofemoral arthritis on postoperative anterior knee pain in patients,both of which could significantly reduce preoperative anterior knee pain,indicating that severe patellofemoral arthritis did not cause significant anterior knee pain by TKA with patelloplasty and dennerized of retented patellar4.The severity of patellofemoral arthritis should not be used as the standard for TKA patella replacement.