Facet Joint Injections vs Medial Branch Blocks: Diagnosing and Treating Spinal Pain

Back and neck pain can have many causes, but when it stems from the small joints along your spine — called facet joints — specialized procedures can help pinpoint the problem and offer relief. These procedures are known as Facet Joint Injections and Medial Branch Blocks (MBBs).

Both are minimally invasive, outpatient treatments that serve dual roles: they can diagnose the source of your pain and provide significant relief. Let’s break down what they are and why they’re so valuable.

What Are Facet Joints?

Facet joints are small joints located between each pair of vertebrae in the spine. They allow your spine to move and flex while providing stability. Like any other joint in your body, they can become irritated or inflamed due to:

Arthritis
Degenerative disc disease
Injury or trauma
Poor posture or repetitive strain

When these joints become painful, the discomfort is often localized to the neck (cervical spine), mid-back (thoracic spine), or lower back (lumbar spine). In some cases, the pain may radiate to the shoulders, buttocks, or thighs — making it hard to identify the root cause without further testing.

What Are Facet Joint Injections?

A facet joint injection involves injecting a combination of a local anesthetic and a steroid directly into the painful facet joint. The anesthetic provides immediate, temporary pain relief, while the steroid reduces inflammation and may provide longer-lasting relief.

These injections are often used for:

Diagnosis: If your pain improves after the injection, it’s a strong sign that the facet joint is the source of the pain.
Treatment: In some cases, the steroid component can offer weeks or even months of relief.

What Are Medial Branch Blocks?

A medial branch block targets the small nerves (medial branch nerves) that carry pain signals from the facet joints to the brain. Instead of injecting medication into the joint itself, the anesthetic is placed near the nerve responsible for transmitting pain from the joint.

Why do this?

Diagnostic Value: If the block temporarily relieves your pain, it confirms the facet joint as the source.
Precursor to Radiofrequency Ablation (RFA): If the block is successful, you may be a candidate for RFA — a procedure that provides longer-lasting pain relief by disrupting the nerve’s ability to send pain signals.

Diagnostic and Therapeutic Benefits

The dual purpose of these procedures is what makes them so powerful:

Diagnostic: They help determine if the facet joints are truly the source of pain.
Therapeutic: They can reduce pain and inflammation, helping patients return to normal activities more comfortably.

What to Expect During the Procedure

Both procedures are performed under image guidance (usually X-ray or fluoroscopy) to ensure accuracy.

You’ll lie comfortably on a procedure table.
The skin is cleaned and numbed.
A thin needle is guided into the correct location.
Medication is injected, and you’re monitored briefly before going home.

Most people return to light activities the same day.

Is It Safe?

Facet joint injections and medial branch blocks are generally safe with low risk of side effects. Potential risks include:

Temporary soreness at the injection site
Mild bleeding or bruising
Rare allergic reactions or infection

If you’re living with persistent neck, mid-back, or lower back pain, facet joint injections and medial branch blocks can be key tools in identifying the source of your discomfort and finding relief. They’re minimally invasive, quick, and often incredibly informative when it comes to guiding your next steps in treatment.