• What are these injections?
• How should I prepare for the procedure?
• How does the procedure work?
• How is the procedure performed?
• What will I experience during the procedure?
• What are the benefits vs. risks?
• What are the limitations of these injections?
What are these injections?
Each of the vertebrae in our spine is associated with 2 major sensory (touch) and 2 motor (action) nerves, one pair for each side of the body. The human lumbar spine is composed of 5 such vertebrae. These nerves arise from the spinal cord and are contained in a bony and soft tissue space that we refer to as the epidural space. The nerves travel within this bony space from which they exit at different levels; the nerves then descend to our groin, buttocks, legs and feet. Individuals that have spinal stenosis (narrowing of the bony canal) or disc problems may experience leg and foot pain in addition to back pain.
Fluoroscopy will be used to help the doctor place the needle in exactly the right location so the patient can receive maximum benefit from the injection.
How should I prepare for the procedure?
Most critically, it is absolutely necessary to stop all medications that might potentially increase your tendency to bleed excessively. Aspirin, even “baby doses”, plavix and coumadin are the most common medications which have such effects but all anti inflammatory drugs such as ibuprofen, celebrex etc should be discontinued, typically for 5 days. It cannot be emphasized enough that such drugs can only be stopped with permission of the physician who prescribed them for you, such as your internist or cardiologist. When scheduling examinations in our office, our staff will remind you of this caveat.
Every patient being considered for epidural block must have a pre-injection imaging procedure, typically an MR (in some instances, a CT is acceptable) and the study must be brought with the patient (unless it was performed in our office; we store all of our data electronically). It is our very strong preference that the MR be performed in our office since we must review the procedure at the time of injection. We understand that patients may bring a set of films, or a CD of a recent study from another institution but frequently the CD does not open on our computers, or the studies may not have been performed in a manner that we prefer. Bringing a report only of a prior examination is not acceptable and we will not proceed with the injection. All pre injection imaging procedures must be no older than 1 year, or it is likely that we will repeat the MR before injection.
We suggest that patients refrain from large meals prior to injection, but a snack or coffee is permitted.
You should plan to have a relative or friend drive you home after your procedure.
Cortisone type drugs are anti-inflammatory agents, reducing swelling and nerve irritation to allow damaged nerves and joints time to heal, thereby preventing further discomfort. These drugs are injected in such a manner that they coat the affected target areas. Therefore, a lumbar injection could affect the lower back and the nerves traveling to the lower limbs, such as the sciatic nerves. A patient may experience relief for a matter of days up to many months; however, the pain may eventually return, requiring either another injection or an alternative treatment.
How is the procedure performed?
This procedure is done on an outpatient basis.
The injection itself usually takes only 10 minutes to perform but the patient should expect to be in our facility for 45 minutes. You will be positioned on your stomach or side on a special fluoroscopic (x-ray) table that will give the doctor easy access to the injection site(s). The staff will help to make you as comfortable as possible, both during and after the procedure.
The doctor will identify where the injection should be given and will sterilize the skin with an antiseptic solution. He or she will then inject a local anesthetic to help numb the area before administering the epidural injection.
Once the area is numb, the doctor will most likely use imaging guidance to help guide the epidural needle to exactly the right position. When the needle is in place, a small amount of a contrast material (x-ray dye) will be injected so the doctor can ensure the distribution of the medication given. Then, your doctor will slowly inject the medication.
When finished, you will be moved into a chair and allowed to rest for a few minutes. An assistant will make sure you do not have any unfavorable reactions to the medication before you are allowed to leave, usually in 10-20 minutes.
What will I experience during the procedure?
You may have no sensation whatsoever, however you may feel tingling or pressure when the injection is administered. Depending on the amount of swelling in the area, you may experience a burning sensation or some mild discomfort. When the injection is finished, however, any discomfort usually disappears. It is possible to feel "pins and needles" in your legs, depending on the injection site. If you feel any sharp pains, however, tell your doctor immediately.
You should take it easy for the rest of the day, though, and may resume normal activities the next day. Please refer to the post injection instructions that you will receive.
The epidural may not take effect immediately-it is common for improvement in the pain to occur progressively over the first 48 hours. The effects may last for a matter of weeks, and often months.
What are the benefits vs. risks?
Benefits:
- Temporary or prolonged pain relief.
- Temporary or prolonged reduction of inflammation in the region of the spine causing pain.
- Better ability to function in daily life without the restrictions previously caused by pain.
Risks:
- The most common “complications” include rapid heart beat, sleeplessness and flushing of the skin, especially the face, for 24-48 hours after injection. These side effects are uncomfortable but are not dangerous and don't require treatment.
- Temporary increase in pain, typically for 1-2 hours.
- Headache is unusual, but possible.
The following are very rare complications.
- Infection at the injection site.
- Bleeding if a blood vessel is inadvertently damaged.
- Injury to the nerves at the injection site.
- Temporary paralysis (extraordinarily rare).
What are the limitations of these injections?
Occasionally, the effects of such injections are temporary but each individual is different; many patients experience many months of improvement. If needed, the injection may be repeated after a number of weeks or months to receive maximum benefit from the medication. If the injections do not help alleviate your pain, your doctor will most likely recommend a different site of injection or possibly a different therapeutic approach.
You may have heard that these injections are given as a series of three. Such one size fits all directions do not work, and in fact, the “series of three” mantra is an old wives tale. It is our belief that if a properly done procedure (performed with fluoroscopic guidance) fails to produce any significant improvement in symptoms, it is unlikely that a second injection to the exact same area, will be of value. Alternatively, if the first injection provides a 30-50 percent improvement in symptoms, second injections tend to be even more gratifying. Injections may be repeated provided each subsequent injection results in progressive improvement. However, it is rare to give more than 3-4 per year.
© 2006 Mink Radiologic Imaging, Inc.