Comparison of Short-term Results between High-flexion and Standard Posterior Stabilized Rotating Platform Mobile Bearing Prosthesis

Abstract：Objective To compare the results of rotating-platform high-flexion(Depuy,RPF)total knee arthroplasty with rotating-platform standard(Depuy,RP)for clinical and radiographic assessment after a short-term period. Methods We ret-rospectively analyze Patients undergoing standard and high-flexion prostheses replacment in Peking University First Hospital for osteoarthritis from Jan 2013 to Dec 2014. Post-operation results were compared between two groups. The clinical evaluation in-cluded range of motion(ROM),Score of the Hospital for Special Surgery(HSS score),squattingand patellarcrepitus. The radi-ographic evaluation included Insall-Salvati ratio and patellar tilt. Results Totally 48 cases(55 knees),including 14 cases (18 knees)in RP group and 33 cases(37 knees)in RPF group,were followed-up for 7 ~ 31 months. The post-operative range of motion was(124. 17 ± 12. 04)in the RP group and(121. 41 ± 14. 06)in the RP-F group with no statistical difference. The HSS score was 94. 00 ± 4. 61 in the RP group and(92. 59 ± 4. 44)in the RP-F group with no statistical difference. There were no statistical differences in squattingor patellar crepitus(P > 0. 05). The results of X-ray demonstrate that there was statistical differences in postoperative Insall-Salvati Ratio(P ﹦ 0. 03)between RP group and RP-F group,but no difference in postopera-tive patellar tilt(P ﹦ 0. 96). Conclusion Total knee arthroplasty with RP and RPF both showed excellent and predictable re-sults at the short-term follow up. But no significant differences were found between standard and high-flexion rotating-platform mobile-bearing total knee prostheses in terms of ROM,HSS score,squatting. The incidence of patellar crepitus in RPF group was higher than that in RP group with no statistical differences.