Facet Injections, Medial
Branch Blocks

Facet injections are used for patients with low back pain and leg pain stemming from inflammation or irritation of the facet joints. These patients normally do not respond to other conservative means, such as oral anti-inflammatory medication, rest or physical therapy.

Facet blocks are used to diagnose and occasionally treat a number of painful conditions, including twisting work or sports injuries, low back pain without disk disease, facet arthritis, and pain after back surgery without new disk disease. The steroid injected reduces the inflammation and/or swelling of tissue in the joint space. This may in turn reduce pain, and other symptoms caused by inflammation / irritation of the joint and surrounding structures. Facet blocks can be used as a diagnostic test to determine if the patient will benefit from a facet radiofrequency rhizotomy. The pain relief can last from days to years, or in some cases, permanently. The physician uses a relatively short-acting anesthetic to temporarily numb nerves to relieve pain. A long-acting steroid medication is frequently added to the anesthetic to reduce swelling and inflammation, and to provide more lasting pain relief. The procedure takes just a few minutes; fluoroscopy (x-ray) is used so that the exact location of pain can be pinpointed.

How do I prepare for the procedure?
  • Do not eat solid food for at least 6 hours before your procedure.
  • Take your medications as usual, unless your nurse tells you otherwise. When taking your medications, take just enough water to help swallow them, and no more than that.
  • Someone must come with you to drive you home.
  • Arrange for someone to be available to assist you at home, if needed.
  • If you are a diabetic, call prior to your appointment to discuss possible alterations in your insulin dose for that day.
  • If you are on Plavix or Coumadin therapy, you will need to stop it, prior to the procedure. Make sure to notify your nurse and physician, prior to the day of your procedure.
How Is a Facet Block Done? After your injection, you will return to the recovery area for a 15-30 minute observation period. It is important that you have someone to drive you home afterward. In the follow-up visit the physician will inquire about the level of pain relief obtained from the procedure. At the time of your injection, you will be asked to put on a patient gown (opened towards the back), and sign a consent form. Your blood pressure, pulse rate and respiration will also be checked. You will be asked what medications you are presently taking and if you have any allergies to medication. Depending on your pain location and the facet joints to be treated, you will be positioned on your stomach with a pillow under your abdomen [for back], or with a small pillow under your chest and your forehead resting on a small pad [for neck area]. Your blood pressure and heart rate will be constantly monitored. Prior to the procedure, your back will be cleansed with antiseptic solution and the physician will numb the area around the injection. A burning sensation lasting 2-3 seconds is to be expected. You may receive a small dose of Valium, or a similar agent, to help you relax. After that, your doctor will position a special needle into the facet joint. During placement of the needle, you can expect to momentarily feel your usual pain, which lets the doctor know the needle is positioned correctly. He/she will then inject the medication slowly. You can expect to feel pressure, but usually not much discomfort, during the injection. Facet injections are performed using a C-arm fluoroscope (X-Ray machine) to direct needles through the skin and muscles of the back to the path of the sensory nerves that are located in the facet joints. At that point a mixture of anesthetic and a steroid (Depomedrol or triamcinolone) is injected into or around the joints. The Facet Block is temporary, since the medication is eventually absorbed into the body.
How long does the injection take?
The actual procedure may take only 15 to 20 minutes. Nevertheless, you need to allow sufficient time for the legal paperwork, the pre-procedure nursing assessment, the procedure preparation, as well as the recovery period. On the average, you should plan to spend 1 to 2 hours in the facility.
What is actually injected?
The injection consists of a mixture of local anesthetic (like lidocaine or bupivacaine) and a steroid medication (betamethasone). The choice of local anesthetic and steroids is dependent on the location of the block and the desired duration of effects. Occasionally the physician will select a short-acting or a long-acting local anesthetic, without informing the patient of the choice. This helps the physician in the evaluation of the effectiveness of the procedure. When the patient returns for evaluation, if the described duration of benefits is concordant with the expected duration of the local anesthetic used, this will provide significant validity to the test.
Will the injection(s) hurt?
The procedure involves inserting a needle through skin and deeper tissues (like a “tetanus shot”). So, there is some discomfort involved. However, we numb the skin and deeper tissues with a local anesthetic using a very thin needle prior to placing the needle near the facet joint. Intravenous sedation is also available.
Will I be “put out” for this procedure?
No. This procedure is done under local anesthesia. If you feel extremely nervous about this procedure, an IV may be placed to give a medication to help you relax. However, physicians frequently try to limit the amount of medication you receive so that you may go home as soon as possible. Let your doctor know how you feel; extra time must be allowed for patients who receive IV medications, sometimes referred to as “conscious sedation.” For “conscious sedation” many doctors use Versed, a fast-acting anti-anxiety medication that helps patients relax, yet remain awake. Patients frequently report partial amnesia (memory loss) regarding the procedure, but do not feel drugged or high afterward. All patients receiving Versed are monitored closely, because the drug can cause a serious drop in blood pressure, heart rate, and breathing in some individuals. Putting a patient to sleep, or even oversedating the patient, may be unsafe, since you loose the ability to monitor correct needle placement, risking the possibility of permanent nerve damage.
What should I expect after the injection?
Immediately after the injection, you may feel that your pain may be gone or significantly reduced. This is due to the local anesthetic injected. This will last 4 to 6 hours. Leg numbness and weakness is rather common after the procedure (when done in the lower back). Arm numbness and weakness is rather common after the procedure (when done in the neck area). This should be self limiting and should wear off in 4 to 6 hours. Your pain will return and may actually feel worse than usual for 5 to 6 days. This is due to the mechanical process of needle insertion as well as initial irritation form the steroid itself. You should start noticing pain relief starting the 5th day or so. This is how long it takes for the steroids, on the average patient, to bring the swelling down to a point where the patient will be able to tell a difference.
What should I do after the procedure?
You should have a ride home. Do not plan on doing anything else for the rest of the day. You should not drive, since you may be under the influence of sedatives (drunk, for all practical purposes). You should avoid making any important decisions, since you may regret them later, as the sedation wears off. We advise the patients to take it easy for a day or so after the procedure. You may feel great, but we advise you against doing things that you were not been able to do while in pain. Remember that this feeling of wellbeing may be secondary to the sedation and the effects of the local anesthetics (numbing medicine), both of which will wear off. Remember to apply ice to the affected area, 15 minutes on and 15 minutes off. Remember to wrap the ice with a towel, to prevent burning the skin. Perform the activities as tolerated by you. Use common sense.
Can I go to work to work the next day?
Unless there are complications, you should be able to return to work the next day or so. The most common thing you may feel is soreness in and around the injection sites.
How long the effect of the medication lasts?
The immediate effect is usually from the local anesthetic injected. The local anesthetics take 15 to 20 minutes for their peak effect. This wears off in a few hours. The steroid starts working immediately after it is injected, but it takes about 5 to 10 days for the patients to see any benefits. This period of time is dependent on the amount of swelling present in the area. The more swelling, the longer it takes for the benefits to be seen. The beneficial effect of the steroids can last anywhere from a couple of days to several months, or even years. The duration of benefits is directly related to the underlying condition. The information on the duration of these medications and their effects is used by your pain physician in interpreting the results of the procedure, and ultimately determining the mechanism of your pain.
How many injections do I need to have?
Possibilities include:
  • If the first injection does not relieve your symptoms in about a week to two weeks, you may be recommended to have one more injection. This is occasionally done, just to make sure that the lack of response was not secondary to a technical difficulty during the procedure (i.e. distorted anatomy secondary to prior surgeries).
  • If your response to the procedure is beneficial, but still have residual pain, you may be recommended to have one more injection. As long as you keep improving with each procedure, you may do up to 3 blocks in a 6 month period.
  • If your pain completely goes away and does not seem to be returning, then there is no need for further treatments.
  • If you get excellent results, but they just do not last, we may recommend changing techniques (i.e. radiofrequency).
Can I have more than three injections?
We generally do not perform or recommend more than three injections in a six-month period. Each case is evaluated individually. If three injections have not helped you, it is very unlikely that you will get any further benefit from more injections. At this point you should consider other alternatives, such as radiofrequency. Also, giving more injections may increase the likelihood of side effects from the steroids.
Will the Facet Joint Injection help me?
It is very difficult to predict if the injection will indeed help you or not. Generally speaking, the patients who have recent onset of pain may respond much better than the ones with long standing pain. Remember that above all, this is a diagnostic procedure meant to help us find the cause of your pain. Even a procedure that does not provide you with relief of the pain, it will provide your physician with invaluable information about the mechanism of your pain, ultimately putting us one step closer to the solution of the problem.
What are the risks and side effects?
Generally speaking, this procedure is safe. However, with any procedure there are risks, side effects, and possible complications. The most common side effect is pain – which is temporary. The other risks involve, infection, bleeding, worsening of symptoms, spinal block, Epidural block etc. The other risks are related to the side effects of steroids: These include weight gain, increase in blood sugar (mainly in diabetics), water retention, suppression of body’s own natural production of cortisone etc. Fortunately, the serious side effects and complications are uncommon.
Who should not have this injection?
If you are allergic to any of the medications to be injected or if you have an active infection going on, you should not have the injection. If you can safely come off of your blood thinners, then you can have the procedure.
What should I expect after the procedure?
You will be given specific instructions to take home. Most patients having a facet injection are pain-free on discharge. For some patients, the pain relief can be long-term; however, it is unusual for one block to completely relieve pain for a long period of time. Keep a pain diary between appointments so that your doctor can work with you more effectively. Your physician will need specific information about your response to treatment so that he can determine whether additional facet injections will help you. Help yourself by following instructions about medications, exercise, relaxation techniques, and sleep aids.
As with everything in medicine, results can vary; you may have complete pain relief, partial relief, or no change in your pain level after the facet block. As in all invasive procedures, there is a small chance of infection or bleeding. Numbness and /or loss of feeling in the back or extremities can last for several hours. Your physician will discuss the risks and benefits of facet blocks with you prior to treatment