INFLUENCE OF BODY MASS INDEX IN REVISION TOTAL KNEE ARTHROPLASTY

Objective: To evaluate the influence of the body mass index (BMI) on the functional assessment of patients who underwent revision total knee arthroplasty (RTKA). Methods: Thirty patients who underwent RTKA between January 2008 and January 2012 were retrospectively assessed using the WOMAC questionnaire. The patients were divided into three groups according to the BMI categories defined by the World Health Organization (WHO): Group I with normal BMI (18-24.9 Kg/m(2)), with eight patients; Group II, overweight (BMI 25-29.9 Kg/m(2)), with 15 patients, and Group III obesity with BMI >= 30 Kg/m(2), with seven patients. The post-operative function scores obtained through the WOMAC questionnaire were compared with the BMI of each group. The statistical analysis between BMI and WOMAC scores was performed with the Spearman correlation test. Results: The average functional WOMAC score for individuals in Group I was 16.7; in Group II it was 47.7; and in Group III it was 69.9, with a statistically significant difference between groups I, II and III (p< 0.0001). Conclusion: Patients with BMI > 25 Kg/m(2) had a worse functional evaluation through WOMAC scores when compared to patients with normal BMI after RTKA.