Facet and Medial Branch Nerve Block


Epidemiology of back pain

In US, approximately 60% to 80% of the population will experience mild back pain at some point in our lives. In 2007 alone, about 27 million US adults aged 18 or older (11% of the total adult population) reported having back pain, according to the Agency for Healthcare Research and Quality. Of the 27 million people, about 19.1 million people sought treatment by a doctor. 

Causes of back pain

The human back is formed by a complex internetwork of nerves, tendons, ligaments, muscles discs and bone structures. At times, the system can develop problems from poor posture, medical conditions, repetitive movements, injury and others. Muscles and ligaments can be strained leading to muscle spasms and tension. There may be damaged discs, disc degeneration, disc herniation, arthritis, synovial cyst (sterile sac of fluid) of the facet joints (joints of the spine), tarlov cysts (sterile sac of fluid found attached to the nerve), fractured or broken bone or disc, slipping of back bone called spondylolisthesis among other causes. Essentially the nerves in the region are inflamed leading to the symptoms.

Just like arthritis of the hands and knees, arthritis does not spare any joints. If you notice an occasional or permanent swelling of the hands, fingers, hips and knees, it is likely arthritis will affect the spine. Joint is where two parts of the bone articulate. The joint of the spine is called a facet joint. The spine is composed of 5 different parts: Cervical, Thoracic, Lumbar, Sacral and Coccyx. Back can have single, but usually has a component of pain from many different sources such as the disc, ligaments, bone, soft tissue, and muscles.

How do you treat arthritic back pain?

The first line of treatment is conservative including over-the-counter medications such as Nonsteroidal Anti-inflammatory Drugs (NSAIDs) and Tylenol. Physical therapy and chiropractic therapy are recommended. If the severity of the symptoms is severe or not responsive to conservative treatment, treatment by a specialist should be sought. There are two different injections for treatment of spine arthritic pain: Facet injections and Medial branch nerve block. Facet injection involves injecting the medication directly into the joint space while medial branch nerve block blocks the nerves that relay pain perception of the joints. The injection can be diagnostic (figure out test) or therapeutic. Once the injection is successful, but does not last a long time, a procedure called rhizotomy or radiofrequency ablation is performed that lasts on average 6 months but can last longer. A facet block or medial branch nerve block has to be performed with good results prior to proceeding with rhizotomy or radiofrequency ablation. 

The medications injected can be a local anesthetic (numbing medicine) or a combination of local anesthetic and a steroid often referred to as cortisone. The local anesthetic temporarily stops the pain perception from the area of the spine injected for hours. If the combination of local anesthetic and steroid is injected, the relief can potentially last months or longer. The injected medication combination decreases the inflammation and the irritation of those nerve roots allowing the body to heal. The local anesthetic provides immediate pain relief while the steroid effect will peak within the week providing more long-term relief. The break in the pain cycle, caused by chemical irritants released by the body, when the medications are injected also provides a longer lasting relief. 

What can be expected on the day of the injection?

Facet injections and medial branch nerve blocks are performed generally at a surgical center and at times in the office procedure suite. Prior to the procedure, all blood thinners need to be stopped after discussing with the prescribing physician unless told otherwise by the physician. Similarly, on the day of the procedure, patients cannot eat by mouth and need an adult to drive the patient and to take care of him/her after the injection. The procedure is classically performed using an X-ray machine called c-arm or fluoroscopy. The needle is guided into the facet joint or the location of the medial branch nerve on the spine. Either a local anesthetic or a mixture of local anesthetic and steroid is injected. 

What can be expected after the injection?

As with any procedures, there are always risks.  Risks can be bleeding, headaches, tissue damage, nerve damage, allergic reaction, and infection. More serious events are very rare such as paralysis and other rare events. Pain procedures have additional safety of x-ray machine. Epidurals and pain procedures have been safely performed under the hands of well trained and qualified physicians for decades.

More often than not, patients tolerate the procedure without any notable side effects. At times, there can be steroid induced effects such as flushing of the face and chest, anxiety, water retention, trouble sleeping and menstrual cycle changes that resolve within days without a need for further treatment. One may experience a temporary continuation or an increase in symptoms post procedure depending on the nerve irritation and severity of symptoms prior to treatment. Patients are asked to have a non-eventful day post procedure to recover from both the injection and anesthesia. Patients generally do well after the facet injection or media branch nerve block resuming normal activities. 

Although there are no guarantees, most patients tolerate the procedure well and are very happy with the results. The symptoms can last from days to months to years. If the treatment is successful, patients receive periodic procedures to maintain pain relief without a need for surgery preventing permanent anatomical changes and other potential consequences. Even after surgeries, certain levels of the facet joints can be addressed as well as rhizotomy or radiofrequency ablation. A complete treatment plan may include periodic or regular medications and adjunctive therapy in addition to other types of injections as our body is complex with interworking of many different parts. 

Contact Houston Pain Specialists for a consultation today at 713-664-2662.


Houston Pain Specialists
5420 Dashwood Dr., Suite 103
Houston, TX 77081
Phone: 713-664-2662
Fax: 713-987-7691

Office Hours

Get in touch