An update on epidural steroid injections: is there still a role for particulate corticosteroids?

Epidural steroid injections (ESIs) play an important role in the multifaceted management of neck and back pain. Corticosteroid preparations used in ESIs may be considered “particulate” or “non-particulate” based on whether they form a crystalline suspension or a soluble clear solution, respectively. In the past two decades, there have been reports of rare but severe and permanent neurological complications as a result of ESI. These complications have principally occurred with particulate corticosteroid preparations when using a transforaminal injection technique at cervical or thoracic levels, and only rarely in the lumbosacral spine. As a result, some published clinical guidelines and recommendations have advised against the use of particulate corticosteroids for transforaminal ESI, and the FDA introduced a warning label for injectable corticosteroids regarding the risk of serious neurological adverse events. There is growing evidence that the efficacy of non-particulate corticosteroids for pain relief and functional improvement after ESI is non-inferior to particulate agents, and that non-particulate injections almost never result in permanent neurological injury. Despite this, particulate corticosteroids continue to be routinely used for transforaminal epidural injections. More consistent clinical guidelines and societal recommendations are required alongside increased awareness of the comparative efficacy of non-particulate agents among specialists who perform ESIs. The current role for particulate corticosteroids in ESIs should be limited to caudal and interlaminar approaches, or transforaminal injections in the lumbar spine only if initial non-particulate ESI resulted in a significant but short-lived improvement.