A Comparative Analysis Of The Postoperative Outcome Of Fixed-Bearing And Mobile-bearing Prosthesis Of Unicompartmental Knee Arthroplasty

Objective:The surgical techniques,postoperative outcomes and the correction of alignment of two kinds of unicompartmental knee arthroplasty(fixed-bearing and mobile-bearing)were compared,so as to provide a reference for clinicians in the selections of prosthesis preoperatively.Methods:Sixty-three patients(seventy-nine knees)who had a unicompartmental knee arthroplasty in The First Hospital of China Medical University from September 2016 to September 2019 was analyzed retrospectively,allotted into fixed-bearing group and mobile-bearing group according to the kind of prostheses(thirty-six for fixed-bearing group and twenty-seven for mobile-bearing group).The changes of Knee Society Score system(KSS),The Western Ontario and McMaster Universities Osteoarthritis Index(WOMAC)and Oxford knee score(OXFORD-12)were compared to evaluate the postoperative recovery of pain and range of motion of knees.The hip-knee-ankle angle(HKA)and femorotibial angle(FTA)were measured preoperatively and postoperatively.The correction of HKA and FTA were used to evaluate the correction of alignment postoperative.Results:The differences between KSS,WOMAC and OXFORD-12 scores of two groups were not significant preoperatively(P>0.05).The difference of KSS score between two groups was not significant(P>0.05).The WOMAC and OXFORD score of Fixed-bearing group was lower than mobile-bearing group,which has a significant difference(P<0.05).The scores of KSS,WOMAC and OXFORD of two groups were significantly better than those before operation(P<0.05).There was no significant difference in HKA and FTA between the two groups before operation(P>0.05).The postoperative HKA and FTA and the correction values of those between the two groups were significantly different(P<0.05).Conclusion:Mobile-bearing UKA and Fixed-bearing UKA are both capable of lessening pain and improving function of anteromedial knee osteoarthritis,with which patients have a satisfying clinical outcome.Two prostheses have no significant difference from the perspective of function.Fixed-bearing UKA has a better subjective feeling in the early postoperative period and mobile-bearing UKA has a larger correction of alignment.