Medial Branch Block (MBB)



Spinal joints can hurt just like elbows, knees, wrists, and hips. Your body uses nerves to signal that a joint is in trouble, causing pain. The nerve which tells your brain there is something wrong with the spinal joint is called the medial branch. So blocking the medial branch silences the pain coming out of a spinal joint for as long as the blocking medication lasts. If you’ve ever had your mouth numbed for dental work, you know that nerve blocks only last a few hours. The same is true for the medial branch blocks for spinal joint pain: it only lasts a few hours.

Since the medial branch block of the spinal joints only lasts a few hours it doesn’t last long enough to be a treatment. In fact, studies have shown just what you would think, that medial branch blocks are not an effective treatment for back pain. So why do we use them? Because they are a lousy treatment, but medial branch block is a great test.

At Phoenix Spine & Joint we do a medial branch block to test if a spinal joint is causing your pain if:

  • Your pain symptoms suggest the spinal joint(s) are the problem
  • MRI shows swelling in the joint
  • The swollen joint is tender to touch

If the block is positive the pain will go away (hopefully completely!), and then come back after a few hours. If you pass the medial branch block test, then Direct Visualized Rhizotomy has a good chance of reducing or eliminating your pain. If not, then your pain is probably coming from a nerve root, or the disc itself.