Facet and Medial Blocks

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Joint inflammation between spinal bones can cause back pain.  Facet and medial blocks involve injecting steroid medication into one or more joint structures to determine if a specific joint generates pain. 

A facet joint block is an injection of local anesthetic and steroid medication into the joint.  A medial block uses similar medication injected outside the joint space near the nerve that feeds a specific joint. Both injection procedures are performed using fluoroscopy.

If pain is relieved, it could mean that the joint or medial nerve generates pain.

Before the Procedure

Patients will get specific advice prior to the procedure. In general, patients will be advised to:

• Stop blood thinners about two days before the test
• Stop aspirin and anti-inflammatory medications about five days before the test
• Stop pain medication about eight hours before the test

Patients will be asked to stop eating and drinking about six hours before the procedure. Although facet and medial blocks are often administered as outpatient procedures, the patient should arrange for someone to drive him or her home after the test.

At the Medical Facility

Upon arrival at the medical facility, patients will be interviewed about their history, condition, medications, allergies, and other relevant information and asked to change into a hospital gown. A nurse will monitor heart function (EKG), blood pressure, blood-oxygen levels (finger oximeter), and other vital signs before, during, and after the procedure.

An intravenous line is placed and patients are given medication to help them relax. Patients are awake during the procedure and will be asked questions by the doctor as the test progresses.

During the Procedure

The procedure is performed in a sterile setting similar to an operating room. The injection site is cleaned and draped.  Numbing medication is injected into and around the procedure site.

The procedure is observed on fluoroscopy, a kind of video x-ray that projects images on monitors in the operating room. The fluoroscope’s C-arm, named for its characteristic C-shape, will be positioned over the patient.

Diagnostic injections may include an anesthetic, steroid, and/or antibiotic. The goal of a diagnostic injection is to relieve the patient’s symptoms. During the procedure, the physician may ask for feedback from the patient.

Possible Complications

A facet and medial block, like other medical procedures, may present risks.  Rare but possible complications include risk of infection, low blood pressure, headache, and injury to nerve tissue.

Patient Restrictions

Some patients should not undergo a facet and medial block.  Patients who may not be appropriate for this procedure are those who are pregnant or breast-feeding or who have:

• Allergy to the contrast medium and/or drugs to be injected
• Anemia
• Significant asthma
• Bleeding problems
• Infection
• Kidney disease
• Severe spinal abnormality

Conclusion

Facet and medial blocks are important to help identify the source of pain. They have benefited many patients with a variety of spinal conditions, but they are not suitable for all patients.