What Is an Epidural Steroid Injection?
An epidural steroid injection is a minimally invasive procedure that delivers a corticosteroid (anti-inflammatory medication) combined with a local anesthetic directly into the epidural space — the area between the outer covering of the spinal cord (dura mater) and the bony vertebral canal. This targeted delivery bathes the inflamed nerve roots in anti-inflammatory medication, reducing swelling, decreasing pain signal transmission, and restoring function.
Unlike oral steroids or pain medications that distribute throughout the entire body, epidural injections deliver medication precisely to the anatomical site of inflammation — maximizing therapeutic effect while minimizing systemic side effects. The procedure is performed under real-time fluoroscopic (X-ray) guidance with contrast dye confirmation to ensure accurate needle placement.
Three Approaches: Interlaminar, Transforaminal, and Caudal
Interlaminar ESI
The needle is inserted between two adjacent vertebral laminae, approaching the epidural space from the posterior (back) midline. This approach provides broad medication distribution across multiple spinal levels — ideal for bilateral symptoms or diffuse spinal stenosis.
Transforaminal ESI (Selective Nerve Root Block)
The needle is directed through the intervertebral foramen — the opening through which the nerve root exits the spinal canal. This approach delivers medication directly to the specific nerve root causing symptoms, providing both therapeutic relief and diagnostic confirmation of the pain generator.
Caudal ESI
The needle is inserted through the sacral hiatus at the base of the spine, allowing medication to flow upward through the caudal epidural space. This approach is particularly useful for lower lumbar and sacral nerve root pathology, including post-surgical epidural fibrosis.
Conditions Treated with Epidural Injections
What to Expect: Before, During, and After
Preparation
You may be asked to stop blood thinners 5–7 days before the procedure. Arrange a driver — you should not drive after sedation. Wear comfortable clothing and arrive 30 minutes early for check-in.
The Procedure (15–30 minutes)
You lie face-down on a fluoroscopy table. The skin is cleaned and numbed with local anesthetic. Under live X-ray guidance, the needle is advanced to the epidural space, contrast dye confirms placement, and the medication is injected. Mild pressure or temporary nerve pain may be felt.
Recovery
You rest in recovery for 30–60 minutes. Most patients experience temporary leg weakness or numbness from the local anesthetic — this resolves within hours. Pain relief may begin within 1–3 days as the steroid takes effect, with maximum benefit at 1–2 weeks.
Suffering from Disc or Nerve Pain?
Our board-certified pain specialists at NYC Pain Management perform fluoroscopy-guided epidural injections in Rego Park, Queens. Most insurance plans accepted.