Analysis of the Resolution Rate of Complications in Obese Joint Replacement Patients

Due to the high risk of complications, the body mass index (BMI) has been a commonly used cutoff metric for joint replacement surgery. However, the percentage of these complications that are treatable has been minimally reported on. This study seeks to quantify the type and incidence of complications that were treated and resolved within 90 days.

The demographics, comorbidities, perioperative variables, and complications were reviewed for 700 patients with BMI >40. 475 patients underwent total knee replacement (TKAs) and 225 underwent total hip replacement (THAs). Univariable and multivariable hierarchically generalized linear mixed models (GLMMs) were utilized to control for relevant covariates.

211 of the total 700 patients had at least one complication. 205 procedures resulted in a medical complication (29.3%), 105 surgeries resulted in a surgical complication (15.0%), 97 procedures required reoperation (13.9%), and 104 procedures required readmission (14.9%). 149 of the 211 (70.7%) complications were treatable. Among hip replacements on patients with a BMI >40, BMI did not demonstrate a significant overall effect on any unadjusted (p=0.94) complication rate or adjusted analysis (p=0.66). Among knee replacements on patients with a BMI > 40, BMI did not demonstrate a significant overall effect on any unadjusted complication rate (p=0.95) or adjusted analyses (p=0.66). BMI stratification was performed (40-44.99, 45-49.99, and > 50), and no appreciable difference in complications, treatable or non-treatable, were observed.

Although high complication rates were observed in this population rate with significant preoperative morbidities, the majority were treatable.