How significantly greater is the risk of infection in severely obese patients who are having their total hip revised? To quantify that answer, researchers from the Netherlands prospectively followed 444 patients who had their total hip replacements revised.
Infection, Obesity and Revised Hips. What’s the Risk?
1 min read Premium comments
#obesitySecondary#infectionrisk#revisiontotalhiparthroplasty#rtha
The study, “Severe obesity increases risk for infection after revision total hip arthroplasty,” appears in the July 27, 2019 edition of The Journal of Arthroplasty.
Joris Bongers, M.D., with the Department of Orthopaedics at Sint Maartenskliniek Nijmegan in the Netherlands explained the hypothesis and genesis of the study to OTW, “We were curious what were the risk factors for complications following revision total hip arthroplasty. Since there are few (prospective) results on this question we analyzed various risk factors on their outcome.”
Bongers and his team measured each patient’s Oxford Hip Score preoperatively and then measured again at the one and two year postoperative intervals. Then they further categorized by body mass index into the cohorts—non-obese (<30 kg/m2, n=328), obese (≥ 30 – 35 kg/m2, n=82) and severely obese (≥ 35 kg/m2, n=34).
Dr. Bongers explained the findings of the study to OTW, “The most important finding is the high infection rate in patients with severe obesity. Subsequently we also deem it important to know that the infection rate increases with a growing obesity class. Another important finding is the rise of complications overall in the severe obese patients.”
“We were not surprised that infection occurs more in patients with high obesity. Studies have previously showed this in primary total hip surgery, and we refer to another study that has shown similar results in revision surgery. But we were surprised with the high relative risks of infection in severe and morbid obese patients compared to non-obese patients.”
“I hope that orthopaedic surgeons take notice of the high risk at developing an infection or any other complication in severe and morbid obese patients following revision total hip surgery. In the preoperative setting this finding can help a surgeon in the decision whether there is an indication for surgery in these patients.”
React:
Discussion
This is a fascinating development. In my practice we've seen similar outcomes with the revised protocol. The key differentiator seems to be patient selection criteria. Has anyone else noticed the correlation with BMI thresholds?
Great point. I'd push back slightly on the conclusion, the sample size in the cited study is too small to draw population-level inferences. That said, the directional signal is compelling and worth a larger RCT.
We implemented a similar approach last year. Early results are promising but we're still gathering 12-month follow-up data. Happy to share our protocol if anyone is interested.
Join the conversation
Orthopedic professionals are discussing this. Sign in and upgrade to read every comment and add your voice.