At least once a week, I hear from a new patient that a friend of theirs recommended “an epidermal” for back pain or this mysterious disease called, “sciatica”. I gently explain that the procedure is called an epidural although we do go through the “epidermal layer” which is the outermost component of the skin.
The term, “epidural” refers to the space between the bony part of the spinal canal and the covering of the spinal cord called the “dura mater”. In pain management, we use this space to inject liquid medications, usually containing a combination of local anesthetics and a corticosteroid. The local anesthetic acts quickly and gives short-term relief while the corticosteroids act slower but give longer-lasting relief. The aim of the injection is to relieve inflammation and nerve irritation, thus, decreasing pain.
There are three techniques interventional pain specialists use in delivering epidural injections in the low back. These are 1) the interlaminar approach 2) the transforaminal approach and 3) the caudal approach. All these procedures are done under x-ray guidance (called fluoroscopy). We also make sure to utilize sterile techniques to avoid infection.
1) Interlaminar Approach:
This is the most common technique. We usually choose this approach when the patient has low back pain radiating down both legs equally or when the MRI of the lumbar spine shows narrowing in the middle of the spine (central spinal stenosis).
2) Transforaminal Approach
When people have low back pain shooting down either leg, this is commonly referred to as “sciatica”. The sciatic nerve is the longest nerve in the human body. It is actually a combination of the 4th, the 5th lumbar spinal nerves, the 1st, the 2nd and the 3rd sacral nerves. These nerves start in the lowest part of the back, come together and exit through the buttocks through an opening called the sciatic notch. The nerve then goes down the entire leg all the way to the foot. When a disc is out of place (disc herniation) or when bone spurs (osteophytes) develop in the spine, the spinal nerves can be irritated. The irritation causes inflammation that produces the pain radiating down the leg. The transforaminal epidural injection is a more targeted approach to delivering medication to the inflamed nerve. This technique involves placing the needle right where the nerves come out from the spine. The spinal nerves exit from the both sides of the spine through the intervertebral foramen (“trans” in Latin means “through” and “foramen” in Latin means “window”).
3) Caudal Approach
The caudal space is located in the tailbone. There is an opening at the end of the sacrum called the sacral hiatus. We use a special needle to access this space and deliver the medication. The liquid goes upward coating the nerves in the process. This technique is very use for people who have had lumbar spine surgery as the scar tissue sometimes makes it difficult to do an interlaminar epidural injection.
A few months ago, epidural steroid injections came into the spotlight because of reported cases of fungal meningitis due to contaminated medications from a private company in Massachusetts. The infection was not due to the procedure itself. It was due to the medication that did not meet safety standards. Needless to say, the whole incident gave epidural injections a bad rap. I always explain to my patients that millions of people die in car accidents every year. It does not mean we have to stop driving. Every procedure has a risk, benefit and alternative. It is the doctor’s responsibility to minimize the risks by taking every possible precaution. This is based on the premise he/she has the proper training for the procedures in the first place.
Talk to your physician. Do not be afraid to ask about their experience. Make sure you understand all the risks involved. Be proactive in your care. Your doctor is on your side. He/she is your ally in controlling your pain. By working together, you will find what works. Real pain management is a team effort. The only reason to play is to play to win.
For more information contact any of Epidurals, or any of our other services, 911 BioCare Centers at 855-901-0911.