Body Mass Index Screening in Knee Arthroscopy: An Analysis Using the National Surgical Quality Improvement Database
William J Rubenstein1, Drew A Lansdown2, Brian T Feeley2
1Department of Orthopedics, University of California San Francisco, San Francisco, CA, U.S.A..
Purpose:
To analyze patients undergoing knee arthroscopy stratified by body mass index (BMI) and assess the tradeoffs in complications avoided versus access to care that occur when instituting BMI eligibility criteria.
Methods:
The National Surgical Quality Improvement Program (NSQIP) database was used to identify patients who underwent knee arthroscopy from 2015 to 2016. Patients were categorized by BMI, and differences in complication rates between BMI categories were assessed. The positive predictive value (PPV) was calculated for various BMI cutoffs, with further analysis performed to identify the number of surgeries that would be denied to avoid a single complication.
Results:
There were 44,153 knee arthroscopy cases identified and an overall complication rate of 1.7%. There was no significant difference found in major complication rate between those with a BMI >40 kg/m2 and those with a BMI <40 (1.7% vs 1.7%, P = .70), and no significant associations between increased complications and a higher BMI were found on binary logistic regression. Instituting a BMI cutoff of 40 has a PPV of 1.7% and would result in the avoidance of 11% of complications while denying 10% of otherwise uncomplicated surgeries. This cutoff would deny 57 surgeries for every complication avoided.
Conclusion:
In patients undergoing knee arthroscopy, this study failed to detect a significant increased risk of major complications associated with having a BMI >40. The institution of BMI eligibility cutoffs would result in low PPVs and a high number of denials for surgery that would otherwise be complication free.
Level Of Evidence:
Level IV, retrospective cohort-based database study.
