What Is a Medial Branch Nerve Block?

It’s an injection that numbs the tiny nerves carrying pain from the facet joints. MBB involves percutaneous placement of a spinal needle adjacent to the medial branch nerves under fluoroscopic guidance, followed by injection of local anesthetic ± corticosteroid to block nociceptive transmission.

Conditions Treated

• Facet joint arthritis (cervical, thoracic, lumbar)
  
  

• Chronic neck pain or low back pain suspected to originate from facet joints
  
  

• Pain that worsens with extension, twisting, or prolonged standing
  
  

• Diagnostic evaluation before Radiofrequency Ablation
  
  

The Medial Branch Block Procedure: Step by Step

Plain-English Overview

1. Preparation: Outpatient procedure with local anesthesia, mild sedation if needed.
   
   

2. Needle placement: Guided by X-ray into the target nerve location.
   
   

3. Anesthetic injection: Small dose of numbing medicine delivered to medial branch nerves.
   
   

4. Observation: If pain is relieved, facet joints are confirmed as the pain source.
   
   

Surgeon-Level Detail

• Positioning: Patient prone; sterile prep and draping.
  
  

• Needle placement: 22–25G spinal needle advanced under AP/oblique/lateral fluoroscopy to the junction of transverse process and superior articular process.
  
  

• Confirmation: Contrast dye ensures correct placement, avoiding vascular spread.
  
  

• Injection: Small volume of anesthetic ± steroid injected.
  
  

• Assessment: Patient’s pain response monitored to confirm diagnostic value.