Epidural steroid injections (ESIs) have been used since the 1950s for many forms of low back pain and leg pain. The spine is made up of bones called vertebrae, with discs in between that allow the spine to be flexible, and many people suffer from disease or other problems related to the spine and discs. An image-guided lumbar epidural corticosteroid injection can help improve flexibility and reduce pain in this area.
Basics and Why It’s Done
This procedure involves the accurate placement of a thin needle into the spine, with assistance from computed tomography (CT) or X-ray images to inject a form of steroid, and often a long-acting anesthetic.
The most common reason for this procedure is severe or chronic back pain, which often extends down into the leg or buttocks on one or both sides, and could be related to aging or arthritis. It’s not recommended for back pain from other causes such as cancer or infection. They may also be recommended for a recurrence of back pain after surgery. In some cases it’s used just to reduce back pain; in others, it is an effective treatment to eliminate or delay the need for back surgery.
Before getting an ESI, be sure you have taken proper steps to prepare:
- •Limit food intake to a light meal only up to two hours before the procedure; you’ll be lying on your stomach, and will be uncomfortable if you’re too full
- •Don’t drink anything in the two hours before the procedure, and use the restroom right before the procedure–anesthetic may cause you to not feel your bladder filling up like normal
- •Wear comfortable clothes that are easy to remove, and leave jewelry at home
- •Wear dark-colored clothing if possible; some disinfectant agents used may stain light-colored clothing
- •Let your radiologist or doctor know if you are taking any blood-thinning medication
- •You may be given a blood test in advance to check for clotting
- •If you have issues lying on your stomach, advise your doctor in advance
- •Arrange to have someone else take you home, as you won’t be allowed to drive after the procedure
The steps of the injection will go as follows:
- •You’ll change into a hospital gown, then be asked to lie on a table on your stomach – either in the CT scanning (please link to CT/CAT Scans for the Brain and Body blog when posted) room or the fluoroscopy suite.
- •A metal marker is taped to your lower back skin, and images or pictures will be used to adjust the position of this marker so it’s at the right level for the injection.
- •The skin is marked with a pen or felt marker to indicate the injection site, and the metal marker will be removed.
- •The skin is cleaned with antiseptic, and a drape may be placed on your back.
- •You’ll get a local anesthetic injection – you will remain awake, and the area of the injection will be numb.
- •A thin spinal needle is guided into the epidural space, with a contrast medium enabling CT images to show that area of the body.
- •Once the needle is properly positioned, a mixture of corticosteroids and sometimes a long-acting anesthetic will be injected. Pain may momentarily increase but will be quickly relieved as the anesthetic does its work
The procedure should take no more than 15 to 20 minutes, though it can take longer if X-ray imaging is used instead of CT imaging. Full recovery, including leg function, bladder function, and blood pressure normalization, generally takes between 30 minutes and an hour. Overall, you should allow four hours between when you arrive at the practice and when you’ll be able to leave – you won’t be allowed to leave until leg function, bladder function and blood pressure are normal and you’re able to walk without feeling dizzy.
Feel free to ask your doctor or clinic for a written report on your procedure, or check the Follow My Health [link to FMH] patient portal 72 hours after your procedure to view the report. This can be provided to your doctor for future reference.
Risks and Side Effects
As noted above, you may feel temporary side effects related to blood pressure, leg numbness or bladder function. Other risks of an image-guided lumbar epidural corticosteroid injection include:
- •Increase in back or leg pain during injection – this is temporary and normal, and as long as you get your procedure done by an experienced medical professional, the overall risk of any complication is extremely low
- •Allergic reaction to contrast dye used to check needle position – this is very rare, with risk of a serious reaction under one in every 100,000 cases
- •Allergic reaction to local anesthetic – also rare, but can occur
- •Urinary retention – the inability to empty your bladder, is uncommon but will require a catheter to help
- •Severe headache – if the fluid sac is punctured by the needle you may experience a severe headache that worsens with standing, sitting, or walking around; the chance of it happening is less than five percent
- •Infection of the epidural space – very rare, and minimized by using sterile techniques; notify your doctor if you have a skin infection on or near your back
- •Bleeding into the epidural space – also very rare, though more common if you’re on blood thinning medication (this is why you’re advised to inform your doctor about these medications)
“Image Guided Lumbar Epidural Corticosteroid Injection.” Inside Radiology. https://www.insideradiology.com.au/ig-lumbar-epidural/
“Lumbar Epidural Steroid Injections for Low Back Pain and Sciatica.” Spine-Health.com. https://www.spine-health.com/treatment/injections/lumbar-epidural-steroid-injections-low-back-pain-and-sciatica