Fig.2: Facet Joints in Motion
What is facet joint injection?
Zygapophysial joints, better known as facet
or “Z” joints, are located on the back (posterior) of the spine on each
side of the vertebrae where it unites the neighboring vertebrae. The facet
joints provide stability and give the spine the ability to bend and twist.
They are made up of two surfaces of the adjacent vertebrae, which are separated by a thin layer of cartilage. The joint is surrounded by a sac-like capsule and is filled with synovial fluid (a lubricating liquid that reduces the friction between the two bone surfaces when the spine moves and also nourishes the cartilage).
Why get a facet joint injection?
There are basically two reasons for having a facet joint injection: for diagnosis (to determine the source of pain) or for therapy (to treat an abnormality that has been detected.)
Most back pain will improve within a few weeks by itself, or with
conservative treatments such as rest, anti-inflammatory medications,
physical therapy and exercise. If you suffer from back pain for more than
4-6 weeks and conservative treatments have not helped, or if your pain has
increased, your physician may order diagnostic tests such as magnetic resonance imaging (MRI) or computerized tomography (CT) scans to look at the structures of the spine. A problem (such as inflammation, irritation, swelling or arthritis) in the facet joint may cause low back pain. If these diagnostic tests show an abnormality in a facet joint, it may be the source of the pain.
To determine if a facet joint is truly the source of back pain, an injection (sometimes called a “block”) may be prescribed. If an injection of a small amount of anesthesia into the facet joint reduces or removes the pain,
we can confirm that the facet joint is the source of the pain. This is diagnostic use of the facet injection.
Once a facet joint is localized as a source of pain, therapeutic injections of anesthesia and anti-inflammatory medications may give pain relief for longer periods of time.
How are the injections performed?
Facet joint injections are performed while you are awake, under a local anesthetic, and able to communicate. Sometimes,
we may prescribe immediate release pain medications (fentanyl lollipop)
and a sedative medication (xanax or ativan) to make you more comfortable during the procedure. The injection is usually performed while you are lying on your stomach on an X-ray table. EKG, blood pressure cuffs and blood-oxygen monitoring devices may be hooked up prior to the injection process.
During the procedure, you probably will undergo a
fluoroscopic X-ray that allows Dr.Thiyaga to place the
medication in the diseased facet joint. An assistant will clean the area of the back directly over the affected joint
with an antiseptic solution of iodine. A local anesthetic medication (lidocaine) is used to
numb the skin over the injection site.
Once the proper site has been accessed, a solution of steroid and local
anesthetic medication is injected into the affected joint. This process may then be repeated depending on the number of affected facet joints.
The procedure usually takes approximately 15 - 30 minutes. Be prepared to
spend about 1 hour in our clinic on the day of the procedure.
Are there special preparations?
Yes, please read our pre-procedure instructions given on this website.
What happens after the injection?
Immediately following the procedure, you may feel a reduction or complete relief of your back pain. Your health care provider may ask you to perform a task that would normally cause pain to assess the level of pain relief. You will be able to walk immediately after the procedure, although some patients may experience leg weakness, numbness or tingling for a few hours after the injection. Because your reaction times may be affected by the medications, driving is not recommended immediately following the injection. You probably should have someone who is able to drive you home following the procedure.
Once home, you can treat any pain you may have at the injection site with ice or a pain medication prescribed by your health care provider. It is generally recommended that you take it easy and not exert yourself for the first day. After the anesthetic component of the injection wears off, your back pain may return. It may take seven to ten days for the steroid component of the injection to relieve the pain. After the first day, you can usually return to your daily activities as your pain will allow; however, you should check with your health care provider to get his or her recommendations on specific activities that will be allowed. In most cases, you can return to work the day following the injection.
How effective are facet injections?
The effectiveness of facet injections for the treatment of low back pain is controversial. No medical study has definitively identified the facet joint as the cause of low back pain. Research has found that facet injections can give relief of lower back pain for longer than six months in 18-63% of patients who underwent the procedure. It has been recommended that facet injections be used as a method to allow the patient to be able to perform other forms of conservative treatment (such as physical exercise, yoga and stretching and bending), rather than using it as a stand-alone pain treatment.
If you do not get pain relief following the first therapeutic facet
joint injections, facet nerve blocks may be tried as an alternate
Who should not receive facet injections?
You should not undergo facet injections for the
treatment of low back pain if your pain has not been present for at least
four to six weeks and if other forms of conservative treatment have not
been tried. You should notify us if you are taking blood thinning
medications for special instructions. If your back pain has been diagnosed as a result of an infection or malignancy, it is also recommended that other forms of pain relief be used.
Are there any side effects?
There is a possibility of side effects with just about any medical procedure and you should always discuss that possibility with your physician before undergoing any treatment. Possible side effects from facet injections include pain at the injection site, bleeding, infection or a worsening of the pain symptoms. Side effects of the steroid medications used may include fluid retention, weight gain, elevated blood pressure, mood swings and insomnia.
As most of the medication is placed inside the painful arthritic joints,
systemic effects of steroids are rarely noticed.
What is evidence in the medical literature to support the
use of facet joint injections for diagnostic and therapeutic purposes?
There are numerous articles supporting the
use of facet injections. Below are listed referenced articles with short
Manchikanti, Laxmaiah et al. Evaluation of Role of Facet Joints in Persistent
Low Back Pain in Obesity: A Controlled, Prospective, Comparative Evaluation.
Pain Physician, vol. 4, No. 3, pp. 266 272, 2001.
This is a controlled prospective study with 100 lower back pain patients that
were divided into two groups, normal and obese. The prevalence of lumbar facet
mediated pain was 40% and obese patients and 36% in normal weight patients.
Laxmaiah et al. Effectiveness of Lumbar Facet Joint Nerve Blocks in Chronic
Low Back Pain: A Randomized Clinical Trial. Pain Physician, vol. 4, No. 1, pp.
101 117, 2001.
This study included 200 lower back pain patients evaluated with controlled
diagnostic blocks for the presence of facet joint pain. 42% of the patients
were determined to have lumbar facet joint mediated pain. These patients were
then treated with a local anesthetic and corticosteroid or Sarapin (a weak
neurolytic agent). After 4 to 6 months, 82% of the patients had reduction of
pain > 50% following 1 -- 3 injections.
Schwarzer et al. Clinical Features of Patients with Pain Stemming from the
Lumbar Zygapophyseal Joints. Spine, vol. 19, No. 10 pp. 1132 1137.
This was a prospective cross-sectional analytic study. There were 176
consecutive patients with lower back pain investigated with screening
zygapophyseal joint blocks using lidocaine and bupivacaine. Results indicate
that 47% of the patients had significant relief following the first facet
Manchikanti, Laxmaiah et al. Pain Physician, vol. 5, No. 3 pp. 243
2002. Prevalence of Cervical Facet Joint Pain in Chronic Neck Pain.
This is a study of the 106 neck pain patients that were seen in an
interventional pain practice in 2001. Results indicate a prevalence of 60% with
a false positive rate of 40% after one block.
Aprill, Charles et al. Cervical Zygapophyseal Joint Pain Patterns II: A
Clinical Evaluation. Spine, vol. 15, No. 6 1990.
This was a study conducted on 10 consecutive neck pain patients referred to the
radiology practice for the investigation of possible zygapophyseal joint pain.
All patients complained of neck pain with referring pain to the head, shoulders,
upper limb. In 8/10 cases there was complete concordance in the predicted levels
between the first and second observers.
Aprill, Charles et al. Cervical Zygapophyseal Joint Pain Patterns I: A Study
in Normal Volunteers. Spine, vol. 15, No. 6 June, 1990.
This was a study in which neck pain patterns were evoked in normal volunteers by
injecting contrast medium into the target joint. Specific referred pain patterns
were generated depending on the joint injected.