Comparison of intermediate term efficacy between posterior stabilized and posterior cruciateretaining total knee arthroplasty

Objective To evaluate the intermediate term efficacy of posterior stabilized (PS) total knee arthroplasty(TKA) and posterior cruciate-retaining(CR) TKA and explore the clinical related problem.Methods The clinical data of 84 patients (87 knees) who treated with primary TKA from May 1992 to May 2006 were analyzed retrospectively.The intermediate term efficacy was compared between PS TKA (PS group,41 cases with 43 knees) and CR TKA (CR group,43 cases with 44 knees).Results All the patients were followed up for 5-10(7.6 ± 1.5 ) years,no infection,dislocation or neurovascular injury occurred in both groups.But 1 knee occurred intraoperative posterolateral femoral condyle fracture in PS group.The lateral retinacular release rate was 2.3％ ( 1/43 ) and 2.3％ (1/44) in PS group and CR group,respectively.The incidence of anterior knee pain was 4.7％(2/43 ) and 4.5％(2/44) after 6 months surgery in PS group and CR group.The incidence of anterior knee pain was 0 at the end of follow-up in both groups.There was no significant difference in the lateral retinacular release rate and the incidence of anterior knee pain between two groups (P ＞0.05).The range of motion and American knee society score (KSS) was similar and no statistical difference was found between two groups(P ＞ 0.05 ).The incidence of patellar tilt or subluxation in X-ray was 2.3％ (1/43) and 2.3％ (1/44) at the end of follow-up in PS group and CR group.There was no significant difference between two groups (P ＞ 0.05 ).At the end of follow-up,no osteolysis,X-ray radiolucent zone and prosthesis loosening were found in both groups.There was no revision owing to loosening or other reasons.Conclusions The intermediate term efficacy of PS TKA and CR TKA is near a tie.However,the future efficacy still need further follow-up. Key words: Arthroplasty,replacement,knee; Treatment outcome