Does the Timing of Preoperative Epidural Steroid Injection Affect Infection Risk After ACDF or Posterior Cervical Fusion?

STUDY

DESIGN

A retrospective database analysis.

OBJECTIVE

The aim of this study was to determine whether any association exists between preoperative cervical epidural steroid injections (CESIs) at various time intervals before anterior cervical discectomy and fusion (ACDF) or posterior cervical fusion (PCF) and the incidence of postoperative infection.

SUMMARY OF BACKGROUND DATA: Although infectious complications following CESI are uncommon, the association between preoperative CESI and postoperative infection following ACDF or PCF has yet to be evaluated in the current literature.

METHODS

A national insurance database was utilized to compare postoperative infection rates within 90 days in patients who received a CESI before ACDF or PCF. Three cohorts were created for each procedure: PCF (n = 402) or ACDF (n = 4354) within 3 months, PCF (n = 586) or ACDF (n = 5183) between 3 and 6 months, and PCF (n = 629) or ACDF (3648) between 6 and 12 months following a CESI. These cohorts were compared with control cohorts who underwent PCF (n = 61,253) or ACDF (n = 241,678) without prior CESI. Postoperative infection rates within 90 days were assessed using International Classification of Disease, 9th Revision (ICD-9) and Current Procedural Terminology (CPT) codes. Odds ratios (ORs), 95% confidence intervals (95% CIs), and P values were then calculated using SPSS. A multivariate binomial logistic regression analysis was performed to determine the independent effect of preoperative injection on postoperative infection following ACDF or PCF controlling for known risk factors for infection, including age, gender, obesity, diabetes, and smoking.

RESULTS

Patients who underwent CESI within 3 months (OR 2.21, P < 0.0001) and within 3 to 6 months (OR 1.95, P = 0.0002) before PCF had significantly increased odds of developing a postoperative infection. Patients who underwent CESI within 3 months (OR 1.83, P < 0.0001) before ACDF had significantly increased odds of developing a postoperative infection.

CONCLUSION

The present study demonstrates that cervical ESI within 6 months of PCF, and within 3 months of ACDF, is independently associated with significantly increased rates of postoperative infection.

LEVEL OF EVIDENCE: 3.