A medial branch block is an injection of medication to determine if the cause of back pain is a facet joint. Facet joints connect the vertebrae of the spine, giving it support and allowing it to bend and twist. Each joint is also connected to two nerves that carry pain signals from the spine to the brain, called medial branch nerves.
A medial branch block is an injection of anesthetic and a steroid near the affected medial branch nerve. If the injection provides pain relief, the pain probably originates in the facet joint. If it does not provide pain relief, then your doctor knows the pain probably does not come from the facet joint and can look for other causes.
If the pain improves from the medial branch block, it can be repeated in the future if the pain worsens again. Short-term pain relief might mean that another procedure, called radiofrequency ablation, could be effective.
A medial branch block may treat pain resulting from:
Procedure and Recovery
This procedure is done in the office under mild sedation. Because of the sedation, you will need someone to drive you home after the procedure.
- You’ll be given mild sedation through an IV to help you relax.
- In the procedure room, you’ll lie on your stomach.
- Your skin where the needle will be inserted will be numbed with a topical anesthetic.
- Your doctor will insert a thin needle into the area being treated, using a fluoroscope (a type of X-ray) for guidance.
- The anesthetic and steroid will be injected, and then the needle will be removed.
- Your injection site will be washed and bandaged.
You can go home after a short recovery period. You should not drive, exercise, or do any strenuous activities for the first 24 hours. You’ll be asked to track the amount and length of your pain relief throughout the rest of the day. Your results will help your doctor determine your next steps.
Risks and Side Effects
Complications from a medial branch block are rare but may include:
- Allergic reaction to the steroid or anesthetic
- Chemical meningitis
- Increased fluid retention in people with a history of fluid retention
- Nerve injury
- Pain at the injection site
- Short-term elevation of blood sugars in people with diabetes
- Spinal cord damage
- Temporary weakness or numbness
This type of block should not be done on someone who has:
- Active infection
- Cold or flu
- Very high blood pressure
- Or who takes blood thinners
If you think a medial branch block is right for you, schedule an appointment today!