Facet Joint Injections
Facet or "Z" (Zygapophysial) joints, are located on the back (posterior) of the spine on each side of the vertebrae where it overlaps the neighboring vertebrae. The facet joints provide stability and give the spine the ability to bend and twist. They are made up of the 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.)Disease, injury, or wear can cause degeneration or deterioration of these joints with pain and restricted movement as a result.
Facet joint injections or "blocks" may provide useful diagnostic information which may help the UPC pain specialist determine the site of spinal pain and whether or not the facet joints are involved, in addition to providing short term relief of symptoms.
The block may be performed at the level of the facet joint itself, or at the level of the ‘median branch nerve’ supplying sensation to the joint. If pain recurs after a successful facet injection, additional procedures such as facet denervation or facet ’rhizotomy’ may be employed for long-term relief of symptoms.
Depending on the location, facet pain and pressure on neighboring nerves may cause ‘referred’ pain symptoms in the form of headaches, shoulder and arm pain, chest and rib pain, and buttock pain.
Why Get A Facet Joint Injection?
There are basically two reasons for 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, antiinflammatory medications, physical therapy and exercise.
However, if you suffer from back pain for more than six 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, your health care provider is assured that the facet joint is the source of the pain. This is diagnostic use of the facet injection. Once a facet joint is pinpointed as a source of pain, therapeutic injections of anesthesia and antiinflammatory medications may be given to achieve pain relief for longer periods of time.
Facet Joint Injection Procedure:
If you are to undergo a facet injection, you should not take any nonsteroidal anti-inflammatory (NSAID) medications (including MotrinTM, AdvilTM, TylenolTM or FeldeneTM) for three days prior to the procedure.
You may also be instructed not to take any prescription pain relievers for at least four hours before the injection.
On the day of the injection you should not have any food or drink (including water) for at least eight (8) hours before the procedure.
However, if you are insulin dependent diabetic, you may not need to change your normal eating habits prior to the procedure and you should discuss this with your UPC Clinic pain specialist. If you need to take medication within four hours before the procedure, a sip of water may be allowed; however, you should check with your UPC specialist prior to taking any medication before the injection.
Facet Joint Injections can be safely performed on an outpatient basis. The skin is always numbed with local anesthetic before careful placement of specially designed small gauge epidural needles. If needed, an I.V. will be started and sedation and other medications will be given. The skin overlying the site of injection is cleaned with antiseptic solution, and covered with sterile drapes.
X-ray (fluoroscopy) may be employed to ensure exact placement of the medication as close to the site of the problem as possible. Radiocontrast dye may be injected to confirm the spread of medications in the intended location unless allergy to these agents is known or suspected.
Once the proper site has been determined, your UPC pain doctor will inject the anesthetic and the anti-inflammatory (steroid) medication.
Afterward, the UPC doctor may ask you to perform a task that would normally cause pain to assess the level of pain relief, to make sure the injection is in the right place and determine if additional injections are needed. This process may then be repeated depending on the number of affected facet joints. At the completion of the procedure the needle and any catheters used to direct the placement of medications are withdrawn and a band-aid dressing is applied.
The overall procedure usually takes approximately 30 to 60 minutes
Immediately following the procedure, you may feel a reduction or complete relief of your back pain. 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.
Post-Procedural Care and Follow-up:
Some of the common recommendations are listed below. However, since the requirements for each patient is different, the University Pain Clinic team may give you specific instructions. As always, feel free to ask our staff if you have any additional questions or concerns
- Avoid being on your feet for 4-6 hours following the epidural injection, and do not drive or operate dangerous equipment or machinery during this time.
- Notify the UPC staff if you experience persistent pain at the injection site, headache that is worse when sitting or standing upright, fever, chills, dizziness, or leg or arm numbness that lasts more than 4-6 hours.
- A drop or two of blood at the injection site is normal. However, you should contact the UPC office if you experience persistent bleeding or drainage at the injection site and then follow all of their instructions for further care.
- 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. The UPC Pain specialist will instruct you regarding permitted activities and pain medication during this time.
- if you have any additional questions or concerns, feel free to contact the UPC Clinic Staff.