Facet Joint Injections
Facet
joints are small joints at each segment of the
spine that provide stability and help guide motion. The facet
joints can become painful due to arthritis of the spine, a back
injury or mechanical stress to the back. A cervical (neck), thoracic
(upper back) or lumbar (lower back) facet joint injection involves
injecting a steroid medication, which can anesthetize the facet
joints and block the pain. The pain relief from a facet joint
injection is intended to help a patient better tolerate a physical
therapy routine to rehabilitate his or her injury or back condition.
Facet joint injections usually have two goals: to help diagnose
the cause and location of pain and also to provide pain relief:
Diagnostic goals:
By placing numbing medicine into the joint, the amount of immediate
pain relief experienced by the patient will help confirm or
deny the joint as a source of pain. If complete pain relief
is achieved while some of the facet joints are numb it means
those joints are likely to be the source of pain.
Pain
relief goals: Along with the numbing medication,
a facet joint injection also includes injecting time-release
cortisone into the facet joints to reduce inflammation, which
can often provide long term pain relief. The procedure may also
be called a facet block, as its purpose is to block the pain.
Anatomy of the Cervical, Thoracic and Lumbar Facet Joints
The facet joints are paired joints in the back and neck, one
pair at each vertebral level (one joint on each side of the
vertebrae). These joints have opposing surfaces of cartilage
(cushioning tissue between the bones) and a surrounding capsule
that is filled with synovial fluid, which reduces the friction
between bones that rub together.
Cervical
facet joints are located on the back or side of the neck. Thoracic
facet joints are in the upper back and lumbar facet joints are
in the lower back. Depending on which joints are affected, pain
can be located in different areas of the body:
Cervical
facet joints. Pain caused by cervical facet
joints is usually felt in the head, neck, shoulder, and/or arm.
Thoracic
facet joints. Pain caused by thoracic facet
joints is typically felt in the upper back, chest and/or arm
(rarely).
Lumbar facet joints.
Pain cause by lumbar facet joints is typically felt in the lower
back, hip, buttock, and/or leg.
Cervical,
Thoracic and Lumbar Facet Joint Injection Procedure
As with many spinal injections, facet joint injections are best
performed using fluoroscopy (live x-ray) for guidance to properly
target and place the needle (and to help avoid nerve injury
or other injury).
The
injection procedure includes the following steps:
• An IV line will be started
so that adequate relaxation medicine can be given, if needed.
The patient lies face down on an x-ray table and the skin over
the area to be treated is well cleaned.
•The physician numbs a small
area of skin with an anesthetic (a numbing medicine). This may
sting for a few seconds.
•The physician uses x-ray
guidance (fluoroscopy) to direct a very small needle into the
joint. Several drops of contrast dye are then injected to confirm
that the medicine only goes into the joint.
• A small mixture of anesthetic
(such as lidocaine)and anti-inflammatory medication (cortisone)
is then slowly injected into the joint.
The
injection itself only takes a few minutes, but the entire procedure
usually takes between thirty and sixty minutes.After the procedure,
the patient typically remains resting on the table for twenty
to thirty minutes, and then is asked to move the area of usual
discomfort to try to provoke the usual pain. Patients may or
may not obtain pain relief in the first few hours after the
injection, depending upon whether or not the joints that were
injected are the main source of the patient’s pain. On
occasion, the patient may feel numb or experience a slightly
weak or odd feeling in the upper back for a few hours after
the injection. On the day of the injection, patients are advised
to avoid driving and avoid doing any strenuous activities.
The patient should record the levels of pain relief during the
next week in a pain diary. Tracking the level of pain is helpful
to clearly inform the treating physician of the injection results
and in planning future tests and/or treatment, as needed.
Facet
Joint Injection Results and Follow-up
On
the day a patient is to receive a facet joint injection, they
are advised to avoid doing any strenuous activities, unless
instructed by their physician. The patient should not drive
the day of the injection unless approved by the treating physician.
If sedation was used, the patient should not drive for 24 hours
after the procedure. Patients may notice a slight increase in
pain lasting for several days as the numbing medicine wears
off and before the cortisone starts to take effect. If the area
is uncomfortable in the first two to three days after the injection,
carefully applying ice or a cold pack to the general area of
the injection site will typically provide pain relief.
If
the facet joints that were treated are the source of the pain,
the patient may begin to notice pain relief starting two to
five days after the injection. If no improvement occurs within
ten days after the injection, then the patient is unlikely to
gain any pain relief from the injection and further diagnostic
tests may be needed to accurately diagnose the patient’s
pain.
Patients
may continue to take their regular pain medicine after the procedure,
with the exception of limiting pain medicine within the first
four to six hours after the injection so that the diagnostic
information obtained is accurate. Patients may be referred for
physical therapy or manual therapy after the injection while
the numbing medicine is effective and/or over the next several
weeks while the cortisone is working.
On the day after the procedure, patients may return to their
regular activities. When the pain is improved, it is advisable
to start regular exercise and activities in moderation. Even
if the pain relief is significant, it is still important to
increase activities gradually over one to two weeks to avoid
recurrence of pain.
If
the facet block procedure is effective in alleviating the patient's
back pain, it is often considered reasonable for the procedure
to be done up to three times per year. However, if the first
facet joint injection does not relieve the patient’s pain
then the injection should not be repeated.