Incidence of component size asymmetry in bilateral total knee arthroplasty patients in National Orthopaedic Hospital, Igbobi, Lagos, Nigeria, West Africa

Background Total knee arthroplasty (TKA) is a common surgical intervention for managing advanced knee osteoarthritis. The symmetry of components in bilateral TKA has been a subject of interest due to its potential impact on clinical outcomes. This study investigates the incidence of component size asymmetry in bilateral TKA patients at the National Orthopaedic Hospital, Igbobi (NOHI), Lagos, Nigeria, West Africa. Objective The study seeks to investigate the prevalence of component size asymmetry in patients undergoing bilateral TKA, emphasizing the importance of awareness regarding this frequent occurrence. This awareness is critical to mitigate the risk of inadvertent selection of incorrect component sizes during time-pressured surgical scenarios. Method The study included 66 eligible patients who underwent bilateral simple primary TKA at NOHI between 2018 and 2022. Data, including age, sex, BMI, component size, operation interval, and preoperative and postoperative knee scores, were retrospectively collected from their operative and postoperative records. Statistical analysis was conducted using SPSS Version 22, and results were presented using relevant tables and charts. A significance level of P less than 0.05 was used for analysis. Result The mean age of patients was 65.4 years (range 51–78 years), with a female-to-male ratio of 4: 1. Obesity was prevalent in 72.7% of patients, while 25.8% were overweight and 1.5% were of normal weight. Component size asymmetry was observed in 45.5% of cases, with 55.5% having symmetrical components. There was a significant improvement in both preoperative and postoperative knee scores across all groups ( P <0.001). No significant difference was found in the distribution of larger size components between the left (19.7%) and right (25.8%) knees. Conclusion Proper sizing of components is paramount for achieving successful outcomes in bilateral TKA. The incidence of component size asymmetry observed underscores the necessity for meticulous preoperative planning and intraoperative decision-making. Surgeons must adhere to accurate sizing protocols, independently measure each knee particularly in time-pressured surgical scenarios, and avoid solely relying on previously operated contralateral knee.