What is an epidural injection?
A medication is injected into the epidural space, or the area surrounding the spinal cord, to provide temporary or long-lasting relief from pain or inflammation. The epidural space is the spinal canal's exterior region. Steroids, anaesthetics, and anti-inflammatory drugs are typically administered via epidural injection. The injection may alleviate pain and inflammation in and around the spinal nerve roots and in and around damaged nerves that may recover over time.
The doctor may use imaging guidance, such as fluoroscopy (multiple x-ray images) or computed tomography (CT or "CAT" scan), to position the needle in the exact location to target the specific area causing the patient's pain, thereby maximizing the patient's benefit from the injection.
What are some common uses of the procedure?
In addition to physical therapy, oral medications, and surgery, physicians use epidural injections to relieve pain in patients who do not respond to conservative treatments.
An epidural injection may be administered to relieve pain brought on by:
- A herniated or bulging disk that causes discomfort by impinging on nerves.
- Spinal stenosis (constriction of the spinal canal)
- Post-surgical "failed back" syndromes (chronic back or leg pain following spinal surgery).
- Other spinal nerve, vertebrae, and adjacent tissue injuries
- Bone spurs
How should I prepare for the procedure?
You will receive detailed preparation instructions, including any necessary adjustments to your regular medication regimen.
You may be instructed not to eat or drink for several hours before your procedure to prevent an unsettled stomach after receiving an injection or because some centres offer sedation.
You may be required to change into a gown for the procedure.
You will likely be required to use the restroom before the procedure.
The doctor will then have simple access to the injection site(s) by positioning you on your stomach or side on a special fluoroscopic or CT table. A nurse and technologist will make every effort to ensure your comfort during and after the procedure.
Plan to have someone drive you home following your procedure.
How does the equipment appear?
The actual injection will be administered with a device similar to routine vaccinations. The doctor will load the syringe with medication from a small vial. The type of medication prescribed depends on the specific requirements of each patient.
The imaging guidance employed, such as fluoroscopy or CT, will necessitate the placement of additional apparatus on the table. Both types of imaging are painless and involve using X-rays to obtain essential images that enable the physician to place the injection needle in the area of interest precisely.
Typically, a radiographic table, one or two X-ray canisters, and a video monitor are used for this examination. Fluoroscopy creates video images from X-rays. It is used to monitor and direct medical procedures. The X-ray equipment and a detector suspended above the exam table produce the video.
The CT scanner is typically a large, donut-shaped device with a brief tunnel in the middle. You will be positioned on a table that slides in and out of this short tunnel. In a gantry, the X-ray tube and electronic X-ray detectors are positioned opposite one another in a ring that rotates around you. The computer workstation in a distinct control room processes the imaging data. Here, the technologist will operate the scanner and visually monitor your examination. The technician can hear and communicate with you via a speaker and microphone.
How is the procedure performed?
Typically, this procedure is performed on an outpatient basis. Nonetheless, some patients may require hospitalization after the procedure. Ask your doctor if you will require hospitalization.
The epidural injection is typically administered in minutes, whereas CT or X-ray machine positioning may take longer.
When you arrive at the office, hospital, or surgical centre, a nurse or technologist may insert an intravenous (IV) line in your arm to administer a sedative during the procedure; this is rarely necessary but will be available if required. On a table in the fluoroscopic or CT scan room, you will be positioned on your stomach or side and made as comfortable as feasible.
The physician will identify the injection site and sterilize the skin with an antiseptic solution before administering the injection. A local anaesthetic is then administered to immobilize the area before the epidural injection.
Once the area is numbed, the doctor will most likely use imaging guidance to position the epidural catheter precisely. Once the needle is in position, a contrast material will be injected so the physician can specifically target the nerves for adequate medication distribution. Your physician will then steadily inject the medication, typically a combination of anaesthetic and anti-inflammatory drugs (cortisone/steroids).
After the procedure, you will be transferred to a chair or bed for a few minutes to an hour of rest. Before you are permitted to leave, the nurse or technician will verify that you have not experienced any adverse drug reactions.
What are the benefits versus risks?
Benefits
- Temporary or long-lasting pain relief.
- Temporary or long-term reduction of inflammation in the painful region of the spine.
- Greater capacity to engage in daily activities without the limitations previously imposed by discomfort.
- It may help determine the source of the discomfort. This is a common issue for patients with multiple potential pain causes.
- Potentially reduces the necessity for invasive procedures.
Risks
- A temporary increase in pain
- Headaches are highly uncommon but possible.
- Reactions to the medication, including hot surges and rashes.
- Infection at the site of injection.
- If a blood vessel gets accidentally damaged, bleeding can occur.
- Nerves are injured at the injection site.
- Temporary paralysis of the nerves that supply the bladder and intestines results in temporary dysfunction of the bladder or intestine.
- When fluoroscopy or CT is utilized, minimal low-level radiation will be emitted.
