Back injections may help treat two major back pain problems: radiculopathy and spinal stenosis. Doctors also use injections for other types of back pain. Sometimes, they also use them to help find out what's causing the pain.
Radiculopathy refers to inflammation or damage to a nerve usually in the neck or the low back. The problem originates where the nerve exits the spine. With radiculopathy, sharp pain shoots from the lower back down into one or both legs or from the neck into the arm. A herniated disc can cause radiculopathy.
With spinal stenosis, the lower spine becomes narrowed. As a result, it compresses the nerves inside. This usually causes pain in the buttock or leg and may or may not be accompanied by back pain. The pain from spinal stenosis may increase with activity. It may also lessen when you lean forward.
Medications for back pain can be injected into the area around the inflamed or damaged nerves. There are several kinds of injections, including:
Epidural means "around the spinal cord." Typically, epidural injections are performed in a doctor's office or the hospital. They're usually given by anesthesiologists, physiatrists, or interventional radiologists with special training.
Before receiving an epidural injection, you will probably undergo an imaging test. This may involve a CT scan or an MRI of the back. The test allows the doctor to identify possible causes of back pain.
At the doctor's office, you will lie face down on a table or special bed. The doctor might give you a sedating medication. But sedation is not usually necessary. The epidural injection takes place in several steps:
The skin will be cleaned and injected with an anesthetic to numb it.
The doctor will insert a needle through the skin toward the spine.
The doctor will use a machine that produces live X-ray video called fluoroscopy. With it, the doctor will maneuver the needle between the bones of the spine.
Using a contrast dye, the doctor will confirm the needle is placed in the epidural space. That's the space between the spine and the spinal cord inside it.
When the needle is in position, the doctor will inject a solution into the epidural space. The solution contains a steroid medicine, also called corticosteroid, and usually an anesthetic medicine, too.
The epidural injection is usually not painful because of the numbing medicine used at the start. Many people do have mild tenderness for up to a few days after the injection.