Medial Branch Blocks

These procedures are for diagnostic purposes and help your physician determine where you pain generators are located and what additional treatment may be helpful in decreasing spine pain.  The medial branches are small nerves that pick up pain from irritated facet or zygapophysial joints, which are small joints located at the back of the spine. When these are helpful, they may be followed by a radiofrequency neurotomy, which can provide longer relief of pain. 

These injections usually contain local anesthetic, which is designed to reduce the pain temporarily for diagnostic purposes.  Depending upon the type of medication used, the pain relief duration will vary.  The duration of relief is important to the physician in determining how effective the blocks are and generally the patient is not informed of the expected duration due to protocol.  To ensure proper placement of the medication, the procedure is performed under fluoroscopic imaging, a low dose type x-ray.

Generally, these procedures are performed in the surgery center.  The patient will be asked to change into a hospital gown.  An IV may be started for medications and safety.  A brief pre-procedure history and physical examination are performed.  All patient medications taken at home will be reviewed to ensure there are no contraindications to the procedure and that the patient has complied with pre-procedure instructions.  The patient will be required to have a complete list of all medication normally taken at home.  The patient is then transported to the procedure room and positioned on an x-ray table.  The skin will then be cleaned with a sterile soap and draped in a sterile fashion.  The skin over the injection target site is then anesthetized with a local anesthetic.  Fluoroscopy is then used to guide a needle into the proper location.  Once the procedure is completed, the patient returns to the recovery area for approximately 30 minutes to rest.

The entire process for check-in, preparation, recovery and check-out will take 1-2 hours.  The procedure itself generally lasts for only 15 minutes, but the rest of the time is necessary to ensure a safe, efficacious procedure. During the injection, pain is sometimes increased temporarily.  The patient will be asked to complete a pain diary after the procedure for several hours to determine the effectiveness of the blocks.

Every medical procedure, no matter how minor, contains some risks.  Anytime, a needle is placed into the body there is a risk of tissue injury, infection and bleeding.  If this occurs near the spine, it can result in nerve damage.  Although extremely rare, nerve damage and death have occurred following spine injections.  Injections near the spine also risk puncturing the dura and can result in headaches, which can easily be treated.  More common risks include a temporary increase in pain, local tenderness after the injection  and  allergic reactions to the medications.

Since this is a diagnostic procedure, the best results are obtained when the patient performs activities that normally increase pain for several hours after the blocks.  This is the only way to determine how effective they were for the patient.  This should be documented on the pain diary.