Medial Branch Blocks (MBB) & Facet Joint Injections
Medial Branch Blocks (MBB) and Facet Joint Injections are precise, minimally invasive procedures used to identify and treat chronic spinal pain stemming from the facet joints—the small stabilizing joints located between each vertebra. These joints can become inflamed due to arthritis, injury, or repetitive stress, leading to pain in the neck, mid-back, or lower back.
MBBs involve injecting a small amount of anesthetic near the medial branch nerves that supply sensation to the facet joints. If pain relief is achieved, this confirms the facet joints as the source of discomfort and may indicate that the patient is a candidate for a longer-lasting treatment such as radiofrequency ablation (RFA).
Facet joint injections, on the other hand, may involve the direct delivery of a steroid and anesthetic into the joint itself for both pain relief and inflammation control.
How It Works
During the procedure, your provider uses fluoroscopic (X-ray) guidance to precisely target the medial branch nerves or the facet joint capsule. A fine needle is inserted at the targeted area, and either a local anesthetic or a combination of anesthetic and corticosteroid is injected.
- Medial Branch Block: Primarily diagnostic; a temporary anesthetic is used to “turn off” the nerve supplying the facet joint. If pain relief occurs, it confirms the joint as the source of pain.
- Facet Joint Injection: Therapeutic; a mixture of anesthetic and steroid is injected directly into the joint to reduce inflammation and improve mobility.
The entire procedure is performed on an outpatient basis and typically takes 20–30 minutes. Most patients can resume light activity shortly after.
Conditions We Treat with MBB
- Cervical facet joint syndrome (neck pain)
- Thoracic facet syndrome (mid-back pain)
- Lumbar facet joint arthropathy (low back pain)
- Spinal osteoarthritis
- Chronic mechanical back or neck pain
- Post-traumatic facet joint pain (e.g., after a motor vehicle accident)
Frequently Asked Questions (FAQs)
What is the difference between a medial branch block and a facet joint injection?
An MBB targets the tiny nerves that send pain signals from the facet joints, mainly for diagnostic purposes. A facet joint injection delivers medication directly into the joint space to reduce inflammation and provide pain relief.
Is this procedure safe?
Yes. Both procedures are low-risk, image-guided, and done under sterile conditions. Most patients experience little to no side effects.
Will I need more than one injection?
Possibly. MBBs may be repeated once to confirm diagnosis before proceeding to radiofrequency ablation. If you’re receiving a therapeutic injection, additional treatments may be scheduled depending on your response.
Can I drive after the procedure?
You should arrange for someone to drive you home, as the injection may cause temporary numbness or weakness in the treated area.
What Types of Results Can I Expect?
- For MBBs: Expect temporary but immediate relief, which helps confirm a diagnosis and guide future treatment.
- For Facet Joint Injections: Relief may begin within 1–3 days and last from several weeks to a few months, depending on the severity of inflammation and your individual response.
- For both: These procedures are often a vital part of a multidisciplinary treatment plan that may include physical therapy, lifestyle modifications, and long-term pain management strategies.
Bibliography
Mayo Clinic. (2023). Facet Joint Injections and Medial Branch Blocks. Retrieved from https://www.mayoclinic.org
American Academy of Orthopaedic Surgeons (AAOS). (2023).
Spinal Pain Management Techniques. Retrieved from https://www.aaos.org
National Institute of Neurological Disorders and Stroke (NINDS). (2023).
Chronic Pain Management Approaches. Retrieved from https://www.ninds.nih.gov