Medial congruent with posterior cruciate ligament resected achieves similar short term outcome as posterior stabilised total knee arthroplasty.

Introduction: Medial congruent (MC) systems and Posterior stabilized (PS) systems are widely utilized as implant options in total knee arthroplasties (TKAs). Nevertheless, determining which system yields superior clinical outcomes remains unresolved. This study seeks to compare these two systems by conducting a retrospective analysis of data from a single surgeon's registry encompassing both systems. Evaluation parameters consist of range of motion (ROM) and various clinical scoring systems.

Methods: A retrospective analysis of data from a single surgeon's registry compared 45 MC with PCL resected (MC-PCLR) TKAs with 44 PS TKAs. Inclusion criteria comprised primary knee osteoarthritis with a minimum 1-year follow-up, while exclusion criteria involved secondary knee osteoarthritis and revision TKAs. Range of motion, Oxford Knee Score (OKS), Knee Society Scoring System (KS) Function Score (KS-FS), and KS Knee Score (KS-KS) were assessed preoperatively, at 3 months, and at 12 months postoperatively. Statistical analysis was performed on retrieved data.

Results: Both group has similar baseline demographics in terms of gender (68% vs. 73% female, p = 0.60), BMI (26.4 ± 5.7 vs. 28.3 ± 5.1 p = 0.81) and American Society for Anaesthesiology score (75% vs. 84% score of 2, p = 0.12), with the exception of age where the PS group is significantly greater (71 ± 8 vs. 66 ± 7 years, p < 0.01). There was no significant difference in range of motion (ROM), Oxford Knee Score (OKS), Knee Society Scoring System (KS) Function Score (KS-FS) and KS Knee Score (KS-KS) for all time periods except for one time stamp where preoperatively, the preoperative KS Knee Score (KS-KS) was significantly lower in the PS group. However, when comparing the change between KS-KS of pre-operation and 3 months post operation (44 ± 18 vs. 31 ± 18,p < 0.01), and pre-operation and 1 year post operation (46 ± 16 vs. 34 ± 17,p < 0.01), it is found to be significantly higher in the PS group for both time periods. All other comparisons between the three time periods were found to have similar parameters.

Conclusions: PS and MC-PCLR demonstrates similar outcomes at the 1-year mark. However PS exhibits a faster rate of improvement from pre-operation to 3 months as compared to MC-PCLR.