Epidural steroid injections do not improve outcomes in patients with lumbar stenosis
A subgroup analysis of the SPORT study found that patients with spinal stenosis who received epidural steroid injections had significantly less improvement compared to those who did not receive them, despite whether patients were treated surgically or nonsurgically.
The research, presented at the 2011 Annual Meeting of the North American Spine Society, also revealed that epidural steroid injected [ESI] patients showed no avoidance to surgery, had longer surgical times and hospital stays.
Epidural steroid injections are a common treatment of lumbar stenosis, study investigator Kris E. Radcliff, MD, said during his presentation. Other studies have reported that epidural steroid injections result in temporary pain relief, possibility for surgical avoidance, and an improvement in short-term outcome. Disadvantages of epidural steroid injections are some studies show an increased rate of surgeries and opioid use in patients with spinal stenosis who receive ESIs.
SPORT subgroup analysis
Based on previous research, Radcliff and colleagues hypothesized that patients given the injections would avoid surgery and have a lower crossover rate to surgery. The study population was patients with lumbar stenosis who were enrolled in the SPORT study. All patients had lumbar spinal stenosis, complaints of lumbar radiculopathy or neurogenic claudication of at least 6 weeks duration, and confirmatory imaging studies. Patients who received ESIs as part of nonsurgical treatment were compared to patients who did not receive ESIs. Patients who received ESIs prior to the study or more than 3 months after enrollment were excluded from the study. Outcome measurements included SF-36, Oswestry Disability Index (ODI) and patient satisfaction scores.
The researchers found no differences in demographics or baseline outcome scores between the groups. Patients who were injected showed less of a preference for surgery than the non-injected group. The researchers also found no significant differences in clinical factors, surgeon-rated stenosis severity or number of levels of stenosis between the groups.
An examination of change in outcome scores from baseline for surgically-treated patients during a 4-year period showed that ESI patients had less improvement than non-injected patients using SF-36 bodily pain domain, ODI and sciatica bothersomeness index scores. Satisfaction at 4 years among surgically treated patients was 40% in the ESI group and 70% in the non-injected group.
Nonsurgically treated patients in the ESI group also showed less improvement compared to the non-injected group using the SF-36 sub scores for bodily pain and physical function, and the SF-36 physical component summary.
Topics of further study
Radcliff noted that the study was limited by the use of fluoroscopic guidance, heterogeneous injection techniques and a variable number of injections.
This was a subgroup analysis, so patients were not randomized to receive epidural injections and we do not know why the patients received epidural injections, he said.
In terms of the etiology or the reason for these results, we wonder if perhaps epidural spinal stenosis is more of a vascular process or maybe some adverse effect of adding volume in the form of an injection of a particulate steroid to an already stenotic spinal canal, Radcliff said. Or, there may be some possible toxicity of either the local anesthetic agents or even the injection procedure itself. But these are topics for further study. by Renee Blisard
- Radcliff K, Kepler C, Hilibrand A, Zhao W, et al. Do epidural steroid injections affect the outcome of patients treated for lumbar stenosis? A subgroup analysis of the SPORT. Paper #49. Presented at the 2011 Annual Meeting of the North American Spine Society. Nov. 2-5. Chicago.
- Kris E. Radcliff, MD, can be reached at 2500 English Creek Ave., #602, Egg Harbor Township, NJ 08234; 609-569-1000; email: firstname.lastname@example.org.
- Disclosure: Radcliff has no relevant financial disclosures.