Intermediate-Term Comparison of Posterior Cruciate-Retaining Versus Posterior-Stabilized Total Knee Arthroplasty Using the New Knee Scoring System

With the dramatic shift in the proportion of younger and more active patients undergoing total knee arthroplasty (TKA), the difference in patient-reported outcomes between cruciate-retaining and posterior-stabilized prostheses will become very important. The goal of this study was to clarify and compare the intermediate-term results of cruciate-retaining and posterior-stabilized TKAs with new patient-derived scores. This study included 60 patients who underwent TKA because of varus-type osteoarthritis (30 patients in the cruciate-retaining group and 30 patients in the posterior-stabilized group) an average of 8 years earlier. The authors investigated patient-reported outcomes using the Knee Society's new scoring system, which was adapted to the diverse lifestyles and activities of contemporary patients undergoing TKA. The results of 48 patients (23 patients in the cruciate-retaining group and 25 patients in the posterior-stabilized group) were assessed. The questionnaire included 7 sections: symptoms, patient satisfaction, patient expectation, walking/standing, standard activities, advanced activities, and discretionary activities. For patient satisfaction, the score of the cruciate-retaining group was slightly but not significantly higher than that of the posterior-stabilized group. No significant difference in score was seen between the cruciate-retaining group and the posterior-stabilized group for any other sections. In addition, no statistically significant difference was seen in range of motion or radiographic alignment postoperatively. After intermediate-term follow-up, the authors found no statistically significant difference in clinical outcomes between patients undergoing cruciate-retaining TKA and those undergoing posterior-stabilized TKA. Additional studies are needed to corroborate and validate these results.