Balancing Act: Infection Risks of Nonoperative Treatments Before Lumbar Fusion

Commentary With the advancement of technology in acupuncture and epidural steroid injections (ESIs), an increasing number of patients are seeking these treatments for back pain prior to surgery. As these techniques gain popularity, clinicians are faced with questions regarding the risks of infection following these treatments. Specifically, surgeons often are asked to describe the optimal time interval between nonoperative treatments and surgery and to describe at which time point an injection may increase the risk of postoperative infection. Given the low rates of infection in spine surgery, Sung and colleagues have conducted a clinically relevant study to address those questions utilizing a large nationwide database. In their article, Sung et al. sought to evaluate whether there was an association between preoperative acupuncture or ESI and spinal infection within 3 months following elective lumbar fusion surgery. Using the Health Insurance Review and Assessment (HIRA) service of the authors’ country along with claims data, they were able to include a large number of subjects in their investigation. While large databases provide greater statistical power, they also present challenges, often related to the lack of granularity associated with the large amount of data. The claims data do not provide specific data important for drawing definitive conclusions, for instance, surgical details (e.g., number of fusion levels or surgical approach), details on where the injections landed anatomically in relation to the surgical site, and data on the type of injections (including non-reimbursed procedures, such as acupuncture involving introduction of a foreign body). The external validation of this large data set within individual practices is difficult due to the lack of granularity in information that is necessary for drawing patient-specific conclusions. We reviewed the literature, looking at rates of postoperative spine infections in lumbar fusion surgery, and found a range of 1.60% to 1.95%1,2. Sung et al. observed an overall infection rate of 4.29%. The authors found that injections performed >2 weeks before surgery did not increase the risk of postoperative infection. However, a systematic review and meta-analysis by Patel et al.3 found that lumbar spine fusion surgery within 30 days of preoperative lumbar spinal steroid injections was associated with higher postoperative infection rates. While there are limitations to the study by Sung et al. involving the use of nationwide claims data, it provides insights into the risks of infection in spine surgery as more people seek nonoperative pain treatments prior to surgery.