What Are Facet Joints?
Facet joints connect the vertebrae, the bones of the spine, in neck, upper back and lower back. They help guide your spine when you move. Facet joints are found on both sides of the spine. Each is about the size of a thumbnail. Facet joints are named for the vertebrae they connect and the side of the spine where they are found The right L4—5 facet joint, for example, joins the 4th and 5th lumbar vertebrae on the right side.
Medial branch nerves are found near facet joints. They communicate pain from the facet joint. They tell the brain when facet joints have been injured. Each facet joint has two or three medial branch nerves that communicate pain.
What Is Facet Joint Pain?
You may feel pain if a facet joint is injured. Sometimes it feels like simple muscle tension. Other times it can be severe pain.
The cartilage inside the joint may be injured. Other times only connecting ligaments surrounding the joint are injured. Facet pain also depends on which joint is affected. The diagrams show areas of pain usually associated with facet injuries.
If you have pain in one or more of these areas, and it has lasted longer than two months, you may have facet pain.
Common tests such as x—rays or MRIs may not show if a facet joint is causing pain. The best way to diagnose facet pain is to block the pain signal in a medial branch nerve.
What Is An RFA?
An RFA uses radiofrequency energy to disrupt nerve function. When this is done to a medial branch nerve, the nerve can no longer transmit pain from an injured facet joint.
What Happens During An RFA?
An RFA may start with an IV (medicine given intravenously) to help you relax. A local anesthetic may be used to numb your skin. The doctor will then insert a thin needle near the facet joint. Fluoroscopy, a type of x-ray, will be used to position the needle.
The doctor will then check to make sure it is at the correct nerve by stimulating it. This may cause muscle twitching and provoke some of your pain.
Once the needle is properly placed, the area will be numbed. Radiofrequency energy will then be used to disrupt the medial branch nerve. This is often performed at more than one level of the spine.
What Happens After An RFA?
You will be monitored after the RFA. When you are ready to leave, the clinic will give you discharge instructions. You may also be given a pain diary. It is important to fill this out because it helps your doctor know how the RFA is working. Take it easy for the rest of the day.
You may feel sore for one to four days. This is normal. It may be due to muscle and nerve irritation Your back may feel numb, weak, or itchy for a couple weeks. Full pain relief normally comes in two to three weeks.
How Long Can I Expect Pain Relief?
Nerves regenerate after an RFA, but how long this takes varies. Your pain may or may not return when the nerves regenerate. If it does, another RFA can be done.