Equivalence of clinical and radiological outcomes in cruciate-retaining and cruciate-substituting total knee arthroplasty with medial pivot knee: A comparative study

Abstract

IntroductionTotal knee arthroplasty (TKA) has been recognized as the most efficacious surgical intervention for individuals suffering from advanced arthritis; however, there is ongoing debate on the technical details of the procedure. It remains unknown whether preservation of the posterior cruciate ligament (PCL) significantly affects the mid-to long-term performance of ADVANCE® medial-pivotal (AMP) knee implants to enhance patient satisfaction. The hypothesis of this study was to investigate whether the preservation of the PCL has a substantial impact on the functional outcomes of medial pivot (MP) implants in patients undergoing TKA. Therefore, this study aimed to compare the midterm clinical and radiographic outcomes of cruciate-retaining (CR) and cruciate-substituting (CS) TKA using MP prostheses. MethodsWe included 376 consecutive patients who underwent unilateral TKA between January 2011 and April 2014. Follow-up evaluations were conducted in April 2021. After propensity score matching analysis, clinical and radiological outcomes and complication rates were compared between patients in the CR and CS groups. ResultsThe postoperative outcomes in the two groups significantly improved the preoperative conditions of the patients (all p > 0.05). The postoperative outcomes (WOMAC score, p = 0.517; KSS, p = 0.107; KSFS, p = 0.240; ROM, p = 0.795; FJS, p = 0.822) and radiographic outcomes (preoperative FTA, p = 0.997; postoperative FTA, p = 0.646; aLDFA, p = 0.094; aMPTA, p = 0.970; PTS, p = 0.243) were comparable between the two groups. The complication and revision rates between the groups were not statistically significant (p = 0.34). The Kaplan–Meier cumulative survival of patients in the CRTKA and CSTKA groups was 100 % and 98.6 %, respectively. ConclusionsThis study supports the hypothesis that when MP prostheses are used, both CR and CS procedures achieve equally good mid-to long-term clinical and radiographic outcomes and complication rates. These findings suggest that PCL preservation may not significantly affect the overall performance of MP implants in patients undergoing TKA.