Overview:
Selective nerve root blocks (SNRBs) are relatively painless needle based procedures. They are a commonly used treatment for both acute and chronic pain conditions. SNRBs are typically used to help reduce inflammation and irritation
around a very specific nerve in the lower back. When these nerves become irritated, they can produce radicular pain. Radicular pain is pain that travels down the nerve and can be felt in your hips or down your legs/feet. Patient’s
often describe this pain as “aching, shooting, burning, tingling, electricity or numbness.”
Conditions commonly treated with selective nerve root blocks:
- Failed back surgery syndrome – continued pain despite surgery to the spine
- Radiculopathy – pain that progresses down your arms/hands or legs/feet
- Stenosis – narrowing of the spinal canal or nerve root exits
- Bulging or herniated discs
- Degenerative Disc Disease
- Sciatica
The procedure:
Please arrive 20 minutes prior to your appointment on procedure day. Our nurses will start an IV if you are requesting sedation and take a pre-operative nurse assessment. All patients are taken to the procedure room on a hospital bed. Once in the procedure room you will be given sedation to help make you comfortable. A cold cleaning solution will be placed on your skin to help decrease chances of infection. The procedure site is then identified by your doctor under x-ray guidance. Once the site is identified a shot of numbing medicine (typically bupivicaine) will be given. This may feel like a bee sting, but will only last a few seconds. The spinal needle is then placed into the position using x-ray guidance. Dye is injected to confirm proper placement of the needle. Medication consisting of steroid (methylprednisilone) and local anesthetics (bupivicaine) is injected through the needle. This medication spreads around and bathes the painful nerve fibers – thus reducing inflammation and alleviating pain. Many patients report this feels like “warm water running down the back or legs.” This feeling can be expected and is actually a sign that the medication is being placed into the correct areas. The needle is then removed and you will be taken to the recovery room. The procedure itself takes 10-15 minutes and then you will be observed for another 15 minutes after the procedure. You may then go home and enjoy the rest of your day.
What to expect after procedure:
The steroid will usually begin working within 3-5 days, but in some cases it can take up to a week to feel the benefits. Most patients will report less pain and can actually do more physical activity and often physical therapy with less pain. The steroids are generally very well tolerated, but some patients may experience side effects, including a flushing, anxiety, trouble sleeping, changes in menstrual cycle, or temporary water retention. Diabetics may also have elevated blood sugars for several days. These side effects are usually very mild and will often resolve within a few days.
Selective nerve root blocks have been performed for many decades, and are generally considered as a very safe and effective treatment for chronic pain conditions. Complications are rare, but could include allergic reaction, bleeding, infection, nerve damage, headaches or paralysis.
Although not everyone obtains pain relief with selective nerve root blocks, often the injections can provide you with improvement in pain and function that last several months or longer. You first series of epidural injections will be done in a set of 3 injections around 3 weeks apart. If you get significant benefit from this entire series, the injections can be safely repeated periodically to maintain the improvements. Injections are also commonly coupled with other treatments (medications, physical therapy, etc) in an attempt to either maximize the benefit or prolong the effects.