Introduction: Epidural steroid injections (ESIs) have been widely used for over 50 years in the treatment of low-back pain with radiculopathy. Most interventional pain physicians strongly believe in their efficacy and safety. Recent Cochrane systematic reviews have disclosed controversial results and have questioned the effectiveness of ESIs. Moreover, a few neurological adverse events have been reported recently.
Methods: A literature search of systematic reviews analysing the effectiveness and complications of ESIs was carried out. The scientific quality of the reviews was assessed using the validated index of Oxman and Guyatt. We relied on data abstraction and quality ratings of the placebo-controlled trials as reported by high-quality systematic reviews.
Results: Two types of systematic reviews were found. The Cochrane high-quality systematic reviews combining the three approaches and different pathologies were predominantly non-conclusive. The second type of review, emanating from the US Evidence-based Practice Centers, distinguishing between the routes of administration and between the principal pathologies found a moderate short-term benefit of ESIs versus placebo in patients with disc herniation and radiculitis, in keeping with the clinical experience. ESIs are generally well tolerated and most complications are related to technical problems. Cases of paraplegia, complicating the foraminal route and related to the violation of a radiculomedullary artery, have been recently reported. They are predominantly observed in previously operated patients.
Conclusions: Epidural steroid injections have a moderate short-term effect in the management of low-back pain with radiculopathy. Severe neurological complications are exceptional, but call for research for alternative approaches to the foramen as well as for means to detect an eventual arterial injury.