Obese and morbidly obese patients are at significantly
greater risk of complications after a total hip reconstruction than non-obese
patients, according to research published in the Medical Journal of
Prof Peter Choong, Director of the Department of Orthopedics
at St Vincent's Hospital, Melbourne, and co-authors conducted a prospective
study of 471 patients who underwent total hip arthroplasty (THA) between 2006
They found that the risk of complications in the first 12
months after THA increased by seven per cent for each unit increase in body
mass index (BMI), after adjusting for age and sex, with morbidly obese patients
having an almost six fold higher complication rate than non-obese patients.
Prof Choong said that despite the significant reduction in
pain and improvement in function reported in obese and morbidly obese patients,
the study found that clinically significant weight loss in these patients after
THA was uncommon.
At 12-month follow-up, only nine per cent of obese or
morbidly obese patients had lost five per cent or more of their preoperative
weight, and 25 per cent had in fact gained five per cent or more of their
"Functional ability is only one of a number of factors that
affect a person's willingness to participate in physical activity (and thus aid
weight loss) after surgery," Prof Choong said.
"Several variables not recorded in our study have been found
to be associated with motivation to participate in physical activity, including
cost, accessibility, knowledge, cultural influences, socio-economic status and
Prof Choong said poorer mental health might present another
barrier to participation in physical activity, with the study finding that
weight gain after THA was associated with poorer preoperative mental health
"Before consenting to surgery, obese patients should be
counseled about the high risk of adverse events," he said.
"Interventions targeting weight loss and health improvement
in obese patients undergoing THA are yet to be tested, and this should be the
focus of future research."
The Medical Journal of Australia
publication of the Australian Medical Association.