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MRgFUS is a noninvasive alternative to facet pain injections.

4 Needles You May Not Want in Your Back

One of the conventional treatments for facet joint pain is x-ray guided injections into the inflamed joints. The facet joints are located between each vertebra (backbone) where the small outer projections of one vertebra meet those above and below. These joints, cushioned with cartilage, allow spinal flexibility (bending and twisting) while at the same time limiting the range of motion. When the cartilage is damaged by injury or arthritis, the joints can become inflamed and compressed, resulting in pain. The areas most affected are either in the upper back by the neck (cervical spine) or lower back by the hips and buttocks (lumbar spine).

There are two cases in which injections into the facet joint may be recommended:

  1. Diagnostic – if an injection of anesthetic into the joint quickly relieves the pain, then the doctor knows that the facet join is at least one source, though muscle pain often accompanies facet joint problems
  2. Treatment – though not curative, injections can alleviate pain for months

What is in the injections?

The ingredients that are injected into the joint are an anesthetic, to ease the pain of the injection, and an anti-inflammatory steroid.

What does the patient experience?

The injections themselves would be quite painful without the local anesthetic, and even with it patient reports vary from a dull pressure to acute pain. Most physicians offer an IV which has a relaxing and sedative effect, and the patient may not remember much about the procedure. Each injection takes about 15 minutes, and generally injections are administered in pairs (left and right facet joint) on up to two vertebrae. It’s common for a patient to have 4 injections during a treatment appointment, but the number will depend on the individual case.

What happens after?

When the local anesthetic wears off in a couple of hours, there may be a return of the pain partly from the injection itself, and partly because it takes 2-7 days for the time release steroid to reduce the inflammation. As that process begins, pain should diminish. How long pain relief will last is unpredictable. Some patients have no relief, some will have weeks of pain-free living, and in the best case, success will last for several months. Most doctors will allow repeat injections twice more in a 12 month period, for a total of three times.

What are the risks?

During treatment injections, both the doctor and the patient are exposed to low doses of ionizing radiation because of the x-ray guidance. This is not usually included in the list of injection risks, but patients who are not comfortable with the idea of radiation should discuss this with their practitioner. Other risks include not only pain during the procedure but increase pain after the anesthesia wears off (usually this clears up as the steroid goes into effect), infection, bleeding, nerve damage, or simply treatment failure to bring relief.

In addition, patients should understand that while the steroid is administered as a local injection, some patients will have systemic side effects from cortisone: weight gain, fluid retention, “hot flashes” (flushing with a feeling a warmth), and diabetics may have increased blood sugar. These are all temporary.

Is there an alternative to injections?

Once a patient has gone through an initial diagnostic round of injections, the idea of injections as treatment may not sound very attractive. There is no guarantee that they will work, and if they do the duration is unpredictable. The procedure can be unpleasant, though compared to chronic facet joint pain it may be the first invasive approach patients will try. However, many patients skip injection treatments and opt for a nerve-deadening procedure called a rhizotomy. After receiving an x-ray guided nerve block injection of anesthetic, a probe is inserted into the nerve where radiofrequency waves create intense heat. This damages the nerve that transmits pain signals, and pain is relieved for about 1-2 years without the use of injected steroids.

Now there is a new, noninvasive way to accomplish the same nerve destruction. It is called MRI-guided Focused Ultrasound (MRgFUS) and involves beaming sound waves to meet precisely at the target area of the nerve, where they generate heat. In one sense, it is similar to the radiofrequency probe in that heat is the effective mechanism, but two major differences are a) magnetic resonance imaging has NO exposure to radiation and b) there is no physical penetration of skin (100% noninvasive). Studies show that MRgFUS is effective for the majority of patients, with few to no negative side effects or risks.

Contact the Sperling Medical Group for more information on how MRgFUS offers a safe and effective pain-free alternative to facet joint injection treatments.

CATEGORY:
Facet Pain