For patients with spinal stenosis, epidural steroid injections (ESI) may actually lead to worse outcomes, whether or not the patient later undergoes surgery, according to an American study in a recent issue of Spine.
“There was no improvement in outcome with ESI whether patients were treated surgically or non-surgically,“ according to the study by Dr Kris E. Radcliff of Thomas Jefferson University, Philadelphia, and colleagues.
The researchers analysed data from the Spine Outcomes Research Trial (SPORT), one of the largest clinical trials of surgery for spinal disorders. In SPORT, patients meeting strict criteria for spinal stenosis (or other common spinal problems) were randomly assigned to surgery or non-surgical treatment such as physical therapy and medications. The current analysis focused on the effects of ESI as part of treatment for spinal stenosis. Dr Radcliff and colleagues compared outcomes for 69 patients who underwent steroid injection during their first three months of enrolment in SPORT versus 207 patients who did not receive ESI. The two groups were similar in terms of most initial characteristics, although patients receiving steroid injections were more likely to prefer non-surgical treatment: 62 versus 33%.
“Despite equivalent baseline status, ESI were associated with significantly less improvement at four years among all patients with spinal stenosis in SPORT,“ the researchers write. Among patients who eventually had surgery, those who had ESI showed less improvement in physical functioning through four years’ follow-up. For those treated non-surgically, steroid injections were associated with less improvement in pain as well as functioning.
There was also evidence that surgery was more complicated in patients who had previously been treated with epidural steroids. On average, surgery took about one-half hour longer in patients who had received ESI, who also spent about one day longer in the hospital. Patients who received ESI were also more likely to “crossover“ from their initially assigned treatment to the other treatment group. There was no evidence that receiving steroid injections helped patients to avoid surgery.
Dr Radcliff and colleagues conclude: “Despite the common treatment practice of incorporating one or more ESI in the initial non-operative management of patients with spinal stenosis, these results suggest that ESI is associated with worse outcome in the treatment of spinal stenosis.“
They believe the “most likely“ reason for the worse outcomes after ESI is that the injection causes worsening of the spinal narrowing or result spinal nerve impingement, although other explanations are possible.