The spine is made up of 24 bones stacked into a column. These bones are the vertebrae. Between each vertebra is a cushion -- the disk -- that acts as a shock absorber between the bones. Every vertebra has two sets of bony knobs that meet between each vertebra. The point where they meet is called the facet joint. (In the neck, these are sometimes called the zygoaphophyseal or apophyseal joints.)
The facet joints allow the spine to flex forward or extend backward. They also allow the spine to twist from side to side. A capsule of soft tissue protects these joint. A fluid -- synovial fluid -- is made in this capsule to lubricate the joints so they move smoothly. A layer of slick white cartilage covers the joint, also helping it to glide smoothly when the body moves.
Over time, the cartilage can get damaged or wear thin. The joints can become enlarged. Spurs of bone may grow on or near the joint. This causes arthritis, pain and swelling in the joints.
Nerves that branch off from the spinal cord pass through the facet joints. They extend nerves into the body to control its activities and movement and receive sensation. These are called nerve roots. The nerves that serve the facet joints themselves are called the medial branches. They carry pain signals to the spinal cord and on to the brain. The pain is a warning sign that a joint is irritated.
The bones of the spine are grouped into three sections. The top part, which connects the skull to the torso is the cervical spine. (The middle portion is the thoracic spine where the ribs attach. The lowest part of the spine is the lumbar spine where the spine connects to the pelvis.)
Cervical Blocks to Diagnose and Relieve Pain
When a person is having pain in the cervical region of the spine, it is important to discover what is causing the pain. Knowing the source allows a doctor to select the best treatment option.
During a cervical block, the doctor injects a pain-relieving fluid into the nerves that serve the neck. A combination of a local anesthetic and cortisone are usually used in the injection. (The anesthetic numbs the pain. The cortisone reduces the swelling.)
The doctor uses X-ray guidance to place the injection in the correct nerve. If the procedure relieves the pain, the doctor knows that nerve is the source of the pain and the target for treatment.
In some cases, the cervical block is all that is needed. In other cases, its effects wear off. If a cervical block successfully numbed the pain, it is likely that a patient will have a good response to radiofrequency ablation. If it does not, the patient probably is not a good candidate for radiofrequency ablation.
Radiofrequency Ablation to Relieve Pain
Radiofrequency ablation uses radio waves to create heat that is used to kill tissue. When the procedure is done on nerve tissue, it can provide relief from pain that hasn¿t been helped by other approaches. It has been used very successfully to treat people who have heart rhythm problems. More recently, it has been used to destroy tumors and treat pain.
Radiofrequency waves are electromagnetic waves that travel at the speed of light (186,000 miles per second).
Radiofrequency ablation gives longer term pain relieve than nerve blocks or other types of injections. Many types of chronic pain respond well to radiofrequency ablation including pain from:
- Injuries such as whiplash
- Neuropathic pain conditions like complex regional pain syndrome or peripheral nerve entrapment syndromes
- Prior spine surgeries
- Spinal arthritis (spondylosis)
What Happens During Radiofrequency Ablation
An intravenous (IV) line will be started before the procedure begins. It will be used to give the patient drugs to make the procedure more comfortable and to calm fears. The area will be carefully cleaned and numbed before the IV line is inserted.
During the procedure, the patient needs to be alert to help the doctor to correctly place the electrode used during the ablation procedure.
The doctor will use X-rays to guide twin, insulated needles to the proper place next to the nerve. A tiny electrode is placed inside the needle. A small radiofrequency current is directed to the medial branch nerve of the joint capsule for 60 to 90 seconds. The radiofrequency waves make heat. This destroys the nerve tissue that is sending the pain signals to the brain.
The procedure is done with sterile technique to minimize the risk of infection.
After the procedure, you will be taken to a recovery area. The nurses will monitor you and be sure you do not have an allergic reaction. You will be allowed to leave once you are stable.
You should rest for about 24 hours. During that time you should not drive a car.
You may feel more pain for several days after the procedure. Your doctor may give you additional pain relieving medications until this goes away. There may be some swelling or bruising where the needle was inserted. A cold pack will help reduce the swelling.
Preparing for Radiofrequency Ablation
The doctor gives patients instructions about how to prepare for radiofrequency ablation. The guidelines usually include instructions such as:
- Arrange for someone to drive you home after the procedure
- Do not eat or drink anything for at least six hours before the ablation. If you take medications, you can do so with a small amount of water. If you have diabetes, you should not take insulin or diabetes pills until after the procedure.
- Do not take aspirin or medicines that contain aspirin for at least 11 days before the procedure. Aspirin can cause bleeding or slow the clotting process.
- Do not wear jewelry
- Shower on the morning of the procedure using bacterial soap to lower the risk of an infection
- Wear clothes that are easy to take off and put on
Pain Relief From Radiofrequency Ablation
How much pain is relieved after the procedure varies from person to person. It can take three or more weeks for the full effects of radiofrequency ablation to be felt. The pain relief may last six months to a year or even longer. Sometimes, nerves do grow back. In such cases, the radiofrequency ablation may need to be repeated.
After the procedure, becomes easier to be more active. Having pain makes it hard to be active. A person who has had a great deal of pain may have weaker muscles. It is important to build up strength and fitness gradually.
While this procedure is a safe, non-surgical treatment with low risks for complications. They sometimes do happen.
Complications from radiofrequency ablation can include infections, numbness or allergic reactions to the medications or contrast dye that may be used during the procedure. The doctor will give you instructions about what to watch for.