The study included 854 nonobese patients with a Body Mass Index (BMI) of less than 30 kg/m², and 336 obese patients with a BMI greater than 30 kg/m², enrolled in the Spine Patient Outcomes Research Trial (SPORT) for the treatment of lumbar disc herniation. Researchers compiled patient demographic and clinical characteristics at baseline, and then compared that information with data compiled during regular follow-up visits for four years.
At four years, improvements in function were less for obese patients - in both the surgical and nonsurgical groups - as measured by the Oswestry Disability Index. Reported pain (using the Short Form-36 scale) was statistically similar for obese and non-obese patients.
"The findings suggest that obese patients with symptomatic lumbar disc herniation do not do as well as nonobese patients with nonsurgical or surgical treatment," said Jeffrey Rihn, MD, associate professor at Thomas Jefferson University Hospital and The Rothman Institute.
Other Key Findings:
- Obese patients did not have an increased rate of infection, intraoperative complications, recurrent disc herniation or reoperation.
- Obese patients had significantly less improvement in the Sciatica Bothersomeness Index and Low Back Pain Bothersomeness Index, but reported no significant difference in self-rated overall improvement/satisfaction.
- The benefit of surgery over nonoperative treatment was not affected by body mass index.
- Recurrence of disc herniation and need for additional surgical procedures did not differ significantly between obese and nonobese patients. This finding contradicts previous studies on this topic.