Total knee replacement in octogenarians, Is age a determining factor in predicting complications? a retrospective cohort study.

introductionGiven the increase in life expectancy in the general population of our country, there is an exponential increase since the last decades of functional older adults who undergo total knee replacement (TKR). There is a direct relationship between the increase in age and the prevalence of both functional and cognitive disabling chronic diseases, however, little we know about whether age is an independent factor in predicting worse functional outcomes and readmissions after TKR. The objective of this study was to evaluate the clinical-functional results and unplanned readmissions within the first 90 postoperative days in patients older than 80 years compared with a control group of patients younger than 80 years.

methodsFrom our institutional patient database, 450 patients who underwent TKR between 2016 and 2019 were retrospectively analyzed. All patients had the medical assurance of Hospital Italiano (Plan de Salud), for which none of these was lost on the follow-up nor were treated in another hospital. Patients were divided in two groups: Group A with 186 patients over 80 years and a control group B with 264 patients between 70 and 80 years. The fragility of these was defined according to the Charlson Comorbidity Index and the Simple Frail Score. Comorbidities were divided in eight groups to define which were the most influential in the final results.

resultsNo significant differences were observed in terms of unplanned readmissions, pain or in functional scores within 90 days between both groups. There was a significant difference in the length of postoperative hospital stay in favor of group A (A: 2.56 SD + - 0.76, B: 4.08 SD =  - 2.23; p = 0.00001). The Charlson score was higher in the group of patients older than 80 years (p = 0.02) as well as the Simple Frail Score (p = 0.004). The ASA score did not show significant differences between both groups.

conclusionAge as an independent factor proved not to be a predictor by itself of unplanned readmissions or worse clinical-functional results in a period of 90 postoperative days between both groups. We believe that the preoperative evaluation of octogenarian patients should be multidisciplinary, with special attention to the identification of comorbidities that can influence the fragility of a patient and the optimization of the pathology.