Outcomes of Kinematically Aligned Total Knee Arthroplasty in Indian Population-Case Series with Three Year Clinical Results.

Abstract

Kinematic total knee arthroplasty (KA) is emerging as an alternative for conventional mechanically aligned (MA) total knee arthroplasty (TKA) for treating patients with osteoarthritis (OA) knee. Since its introduction, concerns remain about the reproducibility and outcomes in different ethnic groups. This study was undertaken to analyse patient-reported outcomes of kinematically aligned total knee arthroplasty using Oxford Knee Score (OKS) in Indian population. A total of 104 consecutive patients (75 females and 29 males) who underwent total knee arthroplasty between February 2016 and February 2018 were included in this prospective study. Only patients with primary OA knee were included, those with rheumatoid arthritis, previous knee surgery were excluded. All surgeries were done by a single surgeon using the same type of cruciate-retaining prosthesis (Vanguard, Zimmer Biomet, Indiana, United States) with the conventional instruments. The principles of kinematic knee alignment were followed. Preoperative and postoperative OKS were recorded. Secondary outcome variables such as Haemoglobin (Hb) drop and blood transfusion rate were noted. The mean age of this group of patients was 65.28years (range 54-83years). 96 patients (108 knees) were available for final review. The average preoperative OKS was 15.71 whereas the average OKS at 2years follow-up improved to 42.07. The mean Hb drop was 1.18g/dl and none of the patients required blood transfusion. This study demonstrates that kinematic alignment TKA provides excellent to good patient satisfaction in Indian population. There were no catastrophic failures in three years of follow-up in this series. The results of KA TKA were not compared to MA TKA in this study and our sample size is not big enough to make recommendations on routine use of this technique. Larger randomised trials in Indian patients are needed to propose solid recommendations. Our pilot data can be useful in calculating sample size for such studies.