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Selective Nerve Root Block

A selective nerve root block (also known as a transforaminal epidural injection) is an injection immediately adjacent to a spinal nerve, which your doctor has identified as a possible cause for your symptoms due to irritation or compression. Under X-ray guidance, we will perform a targeted injection of local anesthetic (freezing) and cortisone (steroid) medications into the tissues surrounding the identified nerve. If this nerve is responsible for your symptoms, this injection is expected to diminish inflammation and provide some relief of your symptoms.

HOW DO I PREPARE FOR MY PROCEDURE?

  • Wear comfortable clothing
  • You must have a driver accompany you to this appointment.
  • You must have had an MRI or CT within the past 24 months.
  • If you’ve had recent surgery, but not updated your images, please inform the booking coordinator prior to injection
  • It is important to be off ALL blood thinners prior to injection. If this is not an option, please hold off on the procedure and consult with your doctor.
  • If you have diabetes, please eat one hour before your appointment.
  • Please arrive 15 minutes prior to your appointment.

WHAT HAPPENS DURING MY PROCEDURE?

  • We will provide you with a comfortable clinic gown to change into.
  • A team member will explain the consent form, procedure details, and answer any questions.
  • We will then escort you to our treatment suite where you will meet the radiologist who will clean the skin and inject a local anesthetic, similar to the freezing you get at the dentist.
  • The needle is then positioned under X-ray guidance and the correct location on the body is confirmed. To double-check the location, a short-acting anesthetic is injected in conjunction with neurologic testing. Once proper needle position is confirmed, the therapeutic medication is then injected.
  • It is possible you will feel pain or pressure similar to your normal back pain as the medicine is injected. This is a good sign and means the medicine is going to the right place. The pain usually disappears quickly.
  • A Band-Aid will be placed at the injection site, then you will be transferred to a wheelchair and brought into another room.
  • After 15 minutes, you will be checked for the expected injection response. If you are able to stand and walk safely, you will be free to leave with your driver.

POST-PROCEDURE INSTRUCTIONS

  • First 24 hours:
    • Keep the treatment area clean. Leave the Band-Aid on. Do not shower.
    • Avoid driving.
    • If possible, please avoid anti-inflammatory medication for 24 hours (i.e., ibuprofen/Advil).
    • A feeling of heaviness, numbness, or tingling in one or both legs is normal and could last for 4-6 hours.
  • First 48 hours:
    • Avoid bathtubs, hot tubs, and pools.
    • Avoid strenuous activities and lifting for 3-5 days.
  • After one week: You may resume strenuous activity, lifting, and physiotherapy. Be mindful of your pain and stop if it hurts too much. Notify your physiotherapist that you have had this injection so they can modify your exercises if necessary.
  • Watch for infection: If you develop worsening pain, skin redness at the site of injection, or a temperature greater than 38.5°C, please proceed to an urgent care or emergency centre.
  • If you have pain or other symptoms beyond 48 hours after your injection, please call our office at 403-568-3890 or email us at paintherapy@radiology.ca during business hours. You may apply heat and ice to the treatment area.
  • Diabetics: Note that cortisone can cause a temporary increase in blood sugar. Please monitor your blood sugar closely and if you have any concerns, consult with your doctor.
  • Anti-coagulant therapy: You will be directed when to resume any anti-coagulant (blood thinners) medication.

WHEN WILL I SEE RESULTS?

  • After your injection, the freezing may last for a few hours. Your symptoms may return until the steroid takes effect in two weeks. Please track your symptom response to share with your physician.
  • These injections typically provide at least three months of symptom relief. If an injection does not help relieve your symptoms, then you may need further evaluation by your referring doctor for another cause of your symptoms.

HOW MUCH WILL IT COST?

This exam is covered under your Alberta Health Care Plan. It is not currently offered at our Saskatchewan clinic.

FOR YOUR APPOINTMENT

Please ensure that you bring your requisition with to your appointment.


DURATION

30-40 minutes

FREQUENTLY ASKED QUESTIONS

How long does the injection take to work?

After your injection, the freezing may last for a few hours. Your symptoms may return until the steroid takes effect in two weeks. Please track your symptom response to share with your physician.

How long will the injection last?

These injections typically provide at least three months of symptom relief. If an injection does not help relieve your symptoms, then you may need further evaluation by your referring doctor for another cause of your symptoms.

What are the potential side effects?

Feeling of heaviness, numbness or tingling on the affected leg is normal and can last for 4-6 hours. Some people also experience headaches which typically respond to caffeine, Tylenol or Ibuprofen, proper hydration and lying flat. If your headache hasn’t resolved itself after 24-48 hours, or you cannot employ the above recommendations, please see your referring physician.