Background: Obesity, a growing public health concern, is often
thought to be an important risk factor for postoperative complications. We
hypothesized that body mass index is predictive of complications after
operative treatment of acetabular fractures.
Methods: A retrospective chart review identified 169 consecutive
patients in whom an acetabular fracture had been treated with open reduction
and internal fixation at a level-1 trauma center. The patients were stratified
into four classes according to their body mass index: normal (<25),
overweight (=25 but <30), obese (=30 but <40), and morbidly
=40). The perioperative outcomes that were evaluated included estimated
blood loss, wound infection, nerve palsy, deep venous thrombosis, pulmonary
embolism, and heterotopic ossification. Multivariate general linear models
were used to test for the relationship between body mass index and
perioperative outcomes while controlling for potential intervening variables
(including surgical approach, fracture type, and surgeon experience). Odds
ratios were calculated as well.
Results: When body mass index was measured as a continuous variable,
it was found to have a significant relationship with estimated blood loss (p =
0.003), prevalence of wound infection (p = 0.002), and prevalence of deep
venous thrombosis (p = 0.03). Odds ratio analysis revealed that obese subjects
(body mass index of =30) were 2.1 times more likely than patients of normal
weight (body mass index of <25) to have an estimated blood loss of >750
mL and 2.6 times more likely to have a deep venous thrombosis. Morbidly obese
patients (body mass index of =40) were five times more likely to have a
wound infection.
Conclusions: Body mass index is predictive of complications after
operative treatment of acetabular fractures.
Level of Evidence: Prognostic Level II. See Instructions
to Authors for a complete description of levels of evidence.