Postoperative Nonsteroidal Immunosuppressant Use Within 30 Days of Posterior Lumbar Fusion are Not Associated with Wound and Bone Healing Complications

Introduction: Postoperative administration of immunosuppressants (IS) in patients undergoing posterior lumbar fusion (PLF) is theorized to affect the inflammatory response associated with wound and bone healing, thereby potentially impacting patient’s surgical outcomes. However, studies are yet to evaluate how the use of postoperative nonsteroidal IS impact surgical results and patient recovery.

Methods: Using the Integrated Database of Electronic Health Records, we analyzed 9,542 posterior lumbar fusion (PLF) patients aged 18 and over. The analysis focused on various outcomes over a minimum follow-up duration of two years, including all-cause 30-day readmissions, length of hospital stay (LOS), chronic pain, revision surgery, and specific complications such as pseudoarthrosis, hardware failure, and wound complications. The outcomes of patients who did not receive nonsteroidal immunosuppressive agents (IS) postoperatively (no-IS group, n = 9458) were compared to those administered with IS within a 30-day postoperative period (≤30 IS, n = 84). Nonsteroidal IS medications were defined as interleukin inhibitors, tumor necrosis factor α inhibitors, and selective IS.

Results: After propensity-score matching, the ≤30 IS group did not demonstrate a statistically significant increase in association with LOS (OR=1.97, 95% CI=[0.642, 6.02], p=0.24), 30-day readmissions (OR=1.22, 95% CI=[0.221, 6.68], p=0.82), wound complications (OR=0.658, 95% CI=[0.157, 2.75], p=0.57), pseudoarthrosis (OR=1.04, 95% CI=[0.67, 1.6], p=0.87), hardware failure, or revision surgery (OR=0.231, 95% CI=[0.001, 46], p=0.59)—all compared to the no-IS group. However, patients in the ≤30 IS group did have a statistically significant increased association with chronic pain (OR=8.16, 95% CI=[3.96, 16.8], p< 0.00001).

Conclusion : Based on our analysis, the use of nonsteroidal IS postoperatively in patients who underwent PLF appears to be broadly safe as bone healing and wound complications are not apparent in our analysis. These findings suggests that patients not need to halt their IS treatment after surgery as they are not associated with increased rates of complications.