Lumbar Nerve Root Blocks
A lumbar nerve root block (also called a selective nerve root block or SNRB) is a precise injection of local anesthetic and steroid medication directly adjacent to a specific lumbar nerve root as it exits the spinal canal. Nerve root blocks serve both diagnostic and therapeutic purposes.
Diagnostic Value
When a patient's symptoms — leg pain, numbness, or weakness — could originate from more than one nerve root level, a selective nerve root block can isolate which specific root is responsible. If your leg pain is significantly reduced (by 50% or more) after the block, this confirms that specific nerve root as the pain generator, providing critical information to guide further treatment planning.
Therapeutic Value
Beyond diagnosis, the steroid component of the injection reduces inflammation around the nerve root and can provide weeks to months of pain relief — often enough time to allow natural healing, participation in physical therapy, or avoidance of more invasive procedures.
Conditions Treated
- Lumbar disc herniation with leg pain (sciatica)
- Foraminal stenosis compressing a specific nerve root
- Nerve root irritation after lumbar surgery
- Multi-level disease where the symptomatic level is unclear
The Procedure
Under fluoroscopic guidance, the needle is directed to the specific nerve root foramen at the target level. After contrast injection confirms precise placement, a small amount of local anesthetic with steroid is delivered. Immediate leg pain relief from the anesthetic confirms correct nerve targeting.
After the Block
You will be monitored for 20–30 minutes. We ask that you track your pain relief during the first 2 hours after the block — this is the critical diagnostic window. A pain diary completed that day provides valuable information regardless of whether injection therapy is continued.
Contact Us
Call 516-492-3100 to schedule a lumbar nerve root block for diagnostic evaluation or therapeutic pain relief.