LUMBAR FACET-JOINT AND MEDIAL BRANCH INJECTIONS
Lumbar facet-joint injections are both a minimally invasive treatment for lower-back pain caused by inflamed facet joints, and a diagnostic tool to determine whether facet-joint inflammation is the source of the pain. Facet joints connect each vertebra to the vertebra above and below it. A facet-joint injection, administered either into the joint capsule or its surrounding tissue, combines a long-lasting corticosteroid with a local anesthetic; a medial branch block administered near the nerves that go to the facet joint is done with local anesthetic alone and is used to confirm the source of the pain is from the facet joint. Although the anesthetic provides only very temporary pain relief, the corticosteroid reduces inflammation and can relieve pain for up to a few years. Enduring pain relief from the injection is diagnostically significant, indicating that the pain originates in the facet joint that received the injection.
Lumbar facet-joint injections can be repeated up to 3 times a year for those who experience successful but short-term pain relief. While this treatment is very helpful for certain patients, it is not effective in all cases.
Candidates for Lumbar Facet-Joint Injections
Patients with pain in the lower back, hips or buttocks, or radicular pain that radiates down the upper legs, are likely candidates for facet-joint injections. Facet-joint pain can be the result of injury, spinal stenosis, sciatica or osteoarthritis. Facet-joint injections may be administered after anti-inflammatory medications, a physical therapy or other conservative methods have failed to alleviate symptoms. Although lumbar facet-joint injections can be effective in relieving pain and determining its point of origin, they are not considered safe for a patient who is pregnant, or has an infection or chronic bleeding disorder.
The Lumbar Facet-Joint Injection Procedure
Facet joint injections are done in the office setting and with very small needles; local anesthesia in the skin is usually more painful to place than the small needle, so local anesthesia is used for the injection itself but not usually to numb the skin. The needle is then inserted, using fluoroscopy (an imaging technique) to ensure precise placement, through the back and directly into the facet joint. Once the needle is correctly positioned, a combination of anesthetic and corticosteroid is injected. This procedure takes less than 30 minutes to perform. The patient typically experiences immediate pain relief because of the anesthetic used in the injection, but measurable results of the corticosteroid may take several days to appear. Mild, temporary pain can occur at the injection site, but it can be managed by taking acetaminophen (Tylenol) and applying ice.
Recovery from Lumbar Facet-Joint Injections
After receiving a facet-joint injection, the patient is able to return home shortly thereafter, and resume regular activities the next day. The corticosteroid used in a facet-joint injection may take up to a week to fully relieve pain. During a follow-up visit in about a week, an evaluation is made of how effective the injection has been in lessening symptoms.
A patient is often encouraged to become involved in an exercise program that involves both stretching and strengthening exercises, which can enhance the effects of the facet-joint injection. Some patients experience long-term, sometimes even permanent, pain relief after one injection and require no further treatment; others may need additional treatment a few weeks or months later.
Risks of Lumbar Facet-Joint Injections
Although considered safe, there are risks involved with facet-joint injections. In rare cases, they can cause infection, allergic reaction, bleeding or nerve damage.
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