Interlaminar Epidural Steroid Injections

Back and neck pain are two of the leading causes of disability in the world, with over one-third of cases being predominantly neuropathic or mixed in nature. The classification of spine pain is important as it affects treatment decisions at all levels of care, with epidural steroid injections (ESIs) being widely acknowledged to be more effective for radicular than mechanical spine pain. Among treatments for chronic pain, ESIs represent the most commonly performed procedure, with over 9 million per year being done in the United States alone. Yet, considerable controversy still remains regarding their efficacy and risks. The interlaminar route constitutes the oldest approach to the epidural space and is the most studied form of ESI. Randomized studies comparing interlaminar to transforaminal are mixed regarding whether or not the latter is more effective, but nearly all are characterized by methodological flaws including small numbers of participants. The main limitation of ESI is that the medications are not deposited directly into the ventral epidural space or around the dorsal root ganglia, where the pathology resides. Yet, interlaminar ESIs are ideal in patients with bilateral pain and are widely considered safer than transforaminal injections when depo-steroids are used. In this review, we discuss the evidence supporting interlaminar ESI, technical considerations, complications, and ways to prevent some of them.