Facet vs. Medial Branch Blocks: Which Is Right for Your Spinal Pain?

Chronic back and neck pain affects millions of people every year. When conservative treatments like physical therapy, medications, or lifestyle changes don’t provide enough relief, doctors may recommend minimally invasive injections. Two of the most common options are facet joint injections (also known as facet blocks) and medial branch blocks. While these procedures are often used for similar conditions, they work differently and serve slightly different purposes. Understanding the distinctions can help you feel confident in your treatment plan.

What Are Facet Joints?

Your spine is made up of vertebrae stacked on top of one another. Between each vertebra are facet joints, which act like hinges. These joints give your spine flexibility while keeping it stable. Over time, these joints can become irritated or develop arthritis, leading to pain, stiffness, and inflammation.

Facet joint pain can radiate into the neck, shoulders, lower back, buttocks, or thighs, depending on which part of the spine is affected.

What Is a Facet Joint Injection?

A facet joint injection delivers a mixture of a local anesthetic and corticosteroid directly into the painful joint. This has two main purposes:

• Diagnostic: If the injection provides quick, temporary relief, it confirms that the facet joint is the source of pain.
• Therapeutic: The steroid reduces inflammation in the joint, often providing longer-term relief that can last weeks or even months.

Facet injections are typically recommended for people with arthritis, degenerative disc disease, or chronic spinal pain that seems to be linked to the joints themselves.

What Is a Medial Branch Block?

A medial branch block (MBB) is slightly different. Instead of injecting medication into the facet joint, the doctor targets the medial branch nerves—tiny nerves that carry pain signals from the facet joints to the brain. By numbing these nerves with an anesthetic, the block interrupts the pain signals.

Medial branch blocks are primarily diagnostic. If you feel significant but temporary pain relief after the injection, your doctor can confirm that the facet joints are indeed the problem. This step is often used to determine whether you’re a candidate for a longer-lasting procedure called radiofrequency ablation (RFA), which burns the medial branch nerves to stop pain signals for months or even years.

Key Differences Between Facet Blocks and Medial Branch Blocks

While both procedures are designed to pinpoint and treat facet-related pain, there are some key differences:

• Injection site: Facet blocks go into the joint itself, while medial branch blocks target the nerves outside the joint.
• Purpose: Facet blocks can be both diagnostic and therapeutic, while medial branch blocks are usually diagnostic.
• Duration of relief: Facet injections may last weeks to months; medial branch blocks usually only last hours to days, but they help guide the next step in care.
• Next steps: If facet injections help, they may be repeated occasionally. If medial branch blocks help, RFA may be recommended for longer-term relief.

When Is a Facet Joint Injection the Right Choice?

Facet joint injections may be recommended if:

• Your pain is thought to come directly from an arthritic or inflamed facet joint.
• You have stiffness, localized tenderness, or pain that worsens when bending or twisting.
• You need both a diagnostic tool and potential therapeutic relief.
• You’re not ready or not a candidate for radiofrequency ablation.

Because facet joint injections include steroids, they can reduce inflammation and provide real pain relief in addition to helping with diagnosis. Many patients find this especially useful if their pain flares during daily activity.

When Is a Medial Branch Block the Right Choice?

Medial branch blocks are often recommended if:

• Your doctor suspects facet joints are the source of pain, but confirmation is needed before moving forward with RFA.
• You’ve tried other injections without enough success.
• You’re considering a long-term solution like radiofrequency ablation.

Since medial branch blocks only involve numbing medication (not steroids), they don’t provide lasting relief on their own. Instead, they are a step in the process of confirming the diagnosis and preparing for a more permanent treatment.

What to Expect During the Procedures

Both procedures are outpatient treatments that take less than an hour. Here’s what typically happens:

1. Preparation: You’ll lie on a treatment table, and the area will be cleaned and numbed with a local anesthetic.
2. Guidance: Using fluoroscopy (X-ray guidance), the doctor carefully inserts a thin needle into the targeted joint or near the medial branch nerve.
3. Injection: The doctor injects a small amount of contrast dye to confirm placement, then delivers the medication (anesthetic with or without steroid).
4. Recovery: You’ll rest for a short time before going home. Most people can resume normal activities the next day.

Some patients feel immediate relief, while others may notice improvement over the following days.

Risks and Side Effects

Both procedures are considered safe, but as with any injection, there are potential risks:

• Temporary soreness at the injection site
• Mild allergic reaction to medications
• Bleeding or infection (rare)
• Short-term numbness or weakness in the area

Because facet joint injections often include steroids, repeated use may have limitations due to steroid-related side effects, such as increased blood sugar or weakened tissues.

How Do Doctors Decide Which to Recommend?

The decision between a facet injection and a medial branch block depends on your symptoms, medical history, and treatment goals.

• If your doctor wants to both diagnose and treat at the same time, a facet joint injection may be the first step.
• If your doctor suspects facet pain but is considering radiofrequency ablation, a medial branch block is usually required to confirm the diagnosis before moving forward.

Often, patients may even receive both at different points in their treatment journey.

The Bottom Line

Facet joint injections and medial branch blocks are two valuable tools for identifying and managing spinal pain that originates from the facet joints.

• Facet joint injections can both confirm the source of pain and provide meaningful relief with anti-inflammatory medication.
• Medial branch blocks serve primarily as a diagnostic step to determine whether you’re a good candidate for a longer-term solution like radiofrequency ablation.

If you’re struggling with chronic back or neck pain, talk with a pain management specialist about which approach makes the most sense for you. With the right treatment plan, it’s possible to reduce pain, restore mobility, and improve your quality of life.