Beyond Body Mass Index: A Systematic Review and Meta-Analysis of Adiposity Measures Versus Body Mass Index in...

Area of Science:

• Orthopedic Surgery
• Infectious Disease Epidemiology
• Surgical Risk Assessment

Background:

• Postoperative infections are common after spinal surgery, increasing costs and complications.
• Body mass index (BMI) is a limited measure for obesity-related surgical risk, lacking anatomical specificity.
• Regional fat distribution significantly impacts wound healing and surgical outcomes.

Purpose of the Study:

• To systematically review and compare the predictive value of BMI versus site-specific adiposity metrics for surgical site infections (SSI) in elective spinal fusion.
• To evaluate the reliability of localized fat measurements in assessing infection risk compared to general BMI.
• To inform preoperative risk stratification and infection prevention strategies in spinal surgery.

Main Methods:

• Systematic review following PRISMA guidelines, searching five databases for observational studies.
• Inclusion of studies comparing BMI and regional adiposity metrics for predicting postoperative SSI in spinal fusion.
• Subgroup meta-analysis using a random-effects model to pool odds ratios (ORs) for subcutaneous fat thickness.

Main Results:

• Seven studies met eligibility criteria, consistently showing localized adiposity measures outperformed BMI in predicting SSI.
• Subcutaneous fat thickness demonstrated a statistically significant increased odds of infection (pooled OR 1.09; p=0.0193).
• Significant heterogeneity (I²=84%) was noted across studies.

Conclusions:

• Site-specific adiposity metrics, especially subcutaneous fat thickness, are superior predictors of postoperative infection risk in spinal surgery.
• Integrating regional adiposity assessment into preoperative planning can enhance surgical risk evaluation and infection control.
• Further research is needed to standardize measurement protocols and validate thresholds for diverse spinal procedures.