Low Back Pain Treatment: Radiofrequency for Facet Joint Pain
As I mentioned previously, facet joints are a common and underdiagnosed source of chronic low back pain. Medical studies show that 15-40% of non-sciatica low back pain is caused by facet joint problems. Fortunately, one of the most safe and effective treatments in all of pain medicine (radiofrequency neurotomy) targets facet joint pain specifically.
What are Facet Joints?
Facet joints, properly known as zygopophyseal joints, are small joints that connect each level of your vertebrae. There is one joint on each side of each level of your spine, for a total of 48 facet joints in your body, from your neck to your sacrum. Facet joint disease, or facet joint arthropathy, typically develops in one of two ways. Trauma, especially after motor vehicle accidents, can aggravate some of the joints and cause long-term inflammation. In older patients, arthritis can develop in these joints, just like other joints of the body. The diagram on the upper left of this post illustrates a pair of irritated facet joints in the low back.
What are the Symptoms of Facet Joint Pain in the Low Back?
Facet joint pain is hard to diagnose because the symptoms vary greatly from person to person. It is common for this sort of pain to become worse when bending backwards at the waist, or rotating from side to side. Many patients with this sort of pain describe stiffness of the back. It is often worse in the morning and improves a little with activity. In some patients, the pain can radiate to the buttock or thigh, imitating sciatica. However, studies show that the only universal symptom of facet joint problems is back pain itself, and other symptoms may or may not be present. In other words, facet joint problems can’t be ruled out by your symptoms alone.
Will an X-ray or MRI show Facet Joint Problems?
People with low back pain from facet joint problems will often have subtle findings on X-rays or MRIs that hint toward the diagnosis of facet joint arthropathy. However, this is not always the case. In some cases, painful facet joints appear normal on medical imaging. This means that unlike most painful medical problems, this cause of back pain can’t be diagnosed with just a physical exam and medical imaging.
Medial Branch Block
The gold standard for diagnosing this kind of back pain is a procedure called Medial Branch Block. The idea is that if facet joints are the source of pain, temporarily numbing their small nerves (“medial branch nerves”) will block the pain for a few hours. If they are not the source of pain, blocking those nerves will do nothing. The procedure uses local anesthetic for comfort, X-ray for accuracy, and very thin needles (thinner than the needle for an IV in a premature baby). It only takes a few minutes, and most people are surprised by how little they feel during the procedure.
What are the Treatment Options?
One option is to inject medication (like cortisone) directly into the facet joints. In some patients this works very well, but the medication usually wears off within a few months at most. For most patients, there is a newer and better option: Radiofrequency Neurotomy. (I have discussed how it works previously here.)
The effectiveness of radiofrequency neurotomy is well-established in medical studies. In two separate studies (published in 2005 by van Wijk in the Clinical Journal of Pain and in 2008 by Nath in Spine), patients with facet joint pain were randomized to either receive radiofrequency treatment or a “sham” procedure in which no radiofrequency was used. They were blinded so they did not know if they were receiving radiofrequency treatment or no treatment. After one year, both studies showed that the patients who received the treatment had a significant reduction in back pain, compared to the placebo treatment. Nath’s study also found that radiofrequency treatment improved people’s back and hip movement and overall quality of life. Although the treatment eventually wears off, it tends to last for 9 to 18 months and can be safely repeated.
Figure from van Wijk’s 2005 study in the Clinical Journal of Pain. The black squares show the pain reduction from 3 to 12 months after radiofrequency (RF) neurotomy. The white boxes are the placebo treatment.
Am I a Candidate for Radiofrequency?
In-person evaluation of your low back pain is needed to determine if radiofrequency might work for you. With good medical evidence supporting its use, my consultation and radiofrequency treatment are covered by medical insurance. Radiofrequency can be repeated as often as every 6 months, although most patients require it to be repeated less often. I see many patients every week with this sort of back pain in my Ventura office and would be happy to discuss it with you.
Image Credit: Facet Joint Diagram by BruceBlaus [CC-BY-3.0], via Wikimedia Commons