The spinal cord runs within the bony structure of the vertebral column and is encased by three membranous sacs~ the dura mater, the arachnoid mater, and the pia mater. The pia mater is adherent to the brain and spinal cord. The dura mater and arachnoid mater are adherent to each other, and together are often referred to more simply as the dura. The sub-arachnoid space (between the arachnoici mater and the pia mater) contains spinal fluid (CSF) that bathes and nourishes the spinal cord. The epidural space is between the outer surface of the dural sac and the bones of the vertebral column it completely surrounds the dura but does not contain any fluid. Instead, it is filled with epidural fat and a large network of blood vessels.
Nerves from the upper and lower limbs (including the nerves that make up the sciatic nerve) enter the vertebral column and pierce the dural sac to reach the spinal cord. For various reasons these nerves can become irritated as they enter the vertebral column and cause pain in the lower limbs. This pain is felt as shooting down the lower limb and is referred to as nerve root pain or, technically, radicufar pain (from the Latin radix, a root). The common name for this sort of pain in the low back and leg is sciatica.
How Does An Epidural Steroid Injection Work?
There are two ways in which it is thought that epidural steroid injections may work, however, there is little scientific evidence supporting either of these theories. The first belief is that sortie leg pain involves the inflammation of one or more of the nerves, their covering, or their roots, in the back. The injection of steroids directly into the part of the spinal column called the epidural space is thought to aid in reducing this inflammation.
The other belief is that the corticosteroids act like a local anesthetic and block the pain long enough to allow the body to begin the process of repairing itself.
Transforaminal Epidural Steroid Injection
The chief effect of an epidurar steroid injection is to reduce pain. Pain relief from epidural injections, in conjunction with therapy has been proven to provide long-lasting relief of back and leg pain. On occasion patient’s will get relief for only a few weeks or months, and in those cases the doctor may opt to repeat the procedure Some patients do not experience any pain relief and may in fact suffer an increase in pain and/or other symptoms as detailed later.
How is an epidural steroid injection administered?
Certain medications may increase the risk of complications. If you are taking aspirin you should stop it 5 days prior to the procedure. If you are on Coumadin (warfarin) heparin, Lovenox (enoxoparin), Ticlid (ticlopidine), Plavix (clopidogrel) or other blood thinning agents such as anti-inflammatow agents, please let your physician know at least one week prior to the procedure. You. can continue to use Celebrex (ceiecoxib) before the procedure. Do not take your regular pain medications for six hours before or after the procedure You should continue to take your routine medications (such as high blood pressure and diabetes medications) before the procedure. If you are on antibiotics please notify your physician, have an active infection or fever we will not do the procedure.
You should not eat or drink anything (except your routine medications) for the six hours prior to the procedure; this again, lowers the chance of having complications. You are expected to have a ride to and from the procedure. The procedure usually takes about a half an hour though you may be at the facility for as long as three hours. Once you arrive to the facility, a nurse will place an IV in your arm. After this
has been done and the doctor is ready, you will be taken to the room and positioned on the table. The physician may do the procedure through an opening on the side of the spine where a nerve root comes out (transforaminal approach), through the middle of the neck or back (intralaminar approach), or through a small opening in the sacnjm, near the tailbone (caudal approach) Local anesthetic will be injected into the skin and underlying tissues to decrease the discomfort of introducing the epidural needle.
Caudal Epidural Steriod Injection
Once the local anesthetic is working the epidural needle is advanced into the epidural space using the bones as landmarks. Your physician will use fluoroscopy (a live x-ray) and other technical aids to ensure that the needle is in the right place.
When the needle is in the epidural space, a syringe containing the corticosferoid solution is connected to the needle. After making sure that the needle is not in a blood vessel or in the spinal fluid, the doctor injects the solution slowly. The doctor will ask you to describe how you are feeling while the solution is being injected.
You may briefly feel pins and needles in the arms or legs (depending on the site of injection). You may get a headache. If the needle touches a bone you will feel a sharp local pain. You should tell your doctor about these feelings.
The corticosteroid will be injected with a local anesthetic, however, the dosage and the volume of the steroid and the other components will vary according to the doctors judgment.
Following the injection, you will be asked to stay at the surgery center for about 20-30 minutes until you adequately recover from the anesthesia. While recovering, you will be monitored for any adverse reactions to the procedure. Once you are feeling well enough to walk, you will be allowed to leave with your ride. You are expected to call or follow-up with your phyáician in 5-7 days to let him know how you are feeling. This will help him determine whether or not to perform another injection.
IF YOU HAVE ANY QUESTIONS ABOUT THE PROCEDURE OR ANY OF THE INFORMATION YOU HAVE JUST READ, PLEASE ASK THE STAFF OR YOUR DOCTOR. THEY WILL BE MORE THAN HAPPY TO ANSWER ANY QUESTIONS YOU MAY HAVE.