Comparison of the functional outcome of posterior cruciate-retaining versus posterior cruciate-sacrificing total knee arthroplasty

Abstract

Background: Although being debated for many years, the superiority of either posterior cruciate-retaining (CR) total knee arthroplasty (TKA) and posterior-stabilized (PS) TKA remains controversial. Materials and Methods: We conducted a prospective study on 40 knee replacements which were undertaken at our hospital between July of 2020 and July of 2021 out of which in 30 patients the cruciate ligament was sacrificed and the posterior cruciate ligament was retained in 10 of the knees undergoing surgery. The inclusion criteria were patients of age more than 50 years, with osteoarthritis and rheumatoid arthritis and Kellgren and Lawrence Grade of 3 and 4. The posterior cruciate ligament was retained if it was structurally intact, fixed flexion deformity of <15° a varus or valgus deformity of <10°. The overall average knee score was 84.9 for posterior cruciate-sacrificing and 74.6 for the CR patients as compared to the preoperative score of 43.9 and 37.6. Functional Knee Score was 97.87 and 98.4 for the CS and CR groups, respectively. The preoperative Functional Knee Score was 37.1 and 37.8 in these groups. The WOMAC Score also showed a marked improvement from 67.7 to 24.6 and 27.4 for CS and CR, respectively. Results and Conclusions: Analyzing the total knee scores, the average Knee Society Score for the PS group was 84.90 and that of the CR group was 74.60 and statistical analysis revealed a significant difference in the P value in favor of cruciate-sacrificing prosthesis, signifying that cruciate-sacrificing prosthesis has better functional outcome. The WOMAC Score also showed a marked improvement. In the CS group, it was 24.6, and in the CR group, it was 27.4. Statistical analysis showed a highly significant difference in favor of cruciate-sacrificing prosthesis.