Epidural Steroid Injection
The epidural cavity is the space surrounding the spinal cord, which extends from the skull to the tailbone, and consists of fat, nerves and blood vessels. Nerves in this space can be blocked by injecting an anesthetic, or a constricted nerve can be relieved of pain and inflammation by injecting steroid medication into the epidural space. Caudal epidural injections are administered at the spinal segments of the lower back and tail bone. The injection can also be used as a diagnostic tool to ascertain the location of pain caused by a nerve pinched by vertebral bone herniation or bone spurs.
Caudal epidural injections are recommended to treat conditions such as:
- Sciatica: weakness or pain caused by irritation of the nerve root originating from the lower back
- Herniated/bulging disc: vertebral discs extend beyond the vertebrae, pinching the neighboring nerve
- Degenerative lumbar spinal stenosis: nerve impingement caused due to narrowing of the spinal canal
Caudal epidural injection is contraindicated in those allergic to anesthetic or steroid medication.
You will lie on your abdomen on an X-ray table. Your doctor will administer intravenous medication to help you relax. Your lower back area will be numbed using local anesthesia. Your doctor then inserts a needle into your back just above your tail bone, guided by X-ray imagery. A contrast dye is injected to confirm the epidural space. Following this, your doctor injects a mixture of anesthesia and steroid medication which spreads throughout the epidural space to treat and relieve the inflammation and pain. The procedure takes about 15 minutes and you will be discharged on the same day.
After your procedure, you will be advised to rest and not drive for the next 24 hours. You can commence your normal activities after 24 hours. The effect of the medication starts working after a week, however, if you do not experience improvement within 10-14 days, please consult your doctor.
Risks and complications
Complications from caudal epidural injections are very rare. There is a risk of bleeding or infection at the site of the injections and sometimes headache in case of a puncture of the dura (outer membrane of the spinal cord). You may also have allergic reactions to the medication administered.
Steroids are chemicals that are naturally present in our body. Synthetic steroids are generally used in the treatment of inflammatory conditions such as spinal disc injury and degenerative diseases among others. Epidural refers to the space outside the covering of the spinal cord and inside the spinal canal. The epidural space runs along the length of your spinal cord. Epidural steroid injection (ESI) is a minimally invasive method of delivering steroids to the spinal nerve through the epidural space. The epidural injection procedure is performed with the help of a fluoroscope (live X-ray). It is effectively used to target the direct source of the pain and reduce inflammation. The ESI can be delivered by translaminar, caudal or a transforaminal approach.
Epidural injections are potentially used as a non-surgical procedure for the treatment of inflammation and pain in patients suffering from disc herniation, spinal stenosis and degenerative disc disease. ESI can help relieve pain in the arms, neck, back and legs. It is used for the treatment of inflamed spinal nerves. Patients suffering from spondylolysis and sciatica may also find ESI to be beneficial in relieving pain. ESI is not performed in pregnant women and in people with infections, diabetes or high blood pressure.
Your doctor will review your medical history thoroughly before the procedure. You may be asked to undergo an imaging test to help your doctor plan for the treatment. The doctor might recommend that you stop taking blood thinning medications 3 to 5 days before an ESI. You will be advised to eat light food before the treatment.
The ESI procedure generally takes 15 to 30 minutes. Patients are awake during the procedure. If you feel anxious about the procedure, then the doctor may give you a sedative. You will lie face down on the table. A local anesthesia may be given to numb the skin before giving the injection. The doctor uses fluoroscope (live X-ray) to direct the needle to the epidural space. Steroid medication is delivered to the nerve root close to the area of inflammation. The approach of injection depends on your condition.
- Translaminar ESI: The injection needle is placed directly from the middle of the back to the interlaminar space (between the lamina of 2 vertebrae). This allows your doctor to access the epidural space. The steroids are delivered to the nerve roots on the inflamed area.
- Transforaminal ESI: The injection needle is placed in the neural foramen, on the side of the vertebra. This allows your doctor to access the area outside the epidural space just above the opening of the nerve root. This procedure uses X-ray to help confirm the flow of medication (combined with contrast dye) after injection. It is usually preferred for patients who previously underwent spine surgery.
You will be monitored for a short while after the procedure, during your recovery period. You are encouraged to walk around immediately after the procedure. You may experience mild discomfort at the site of injection. Soreness in and around the injection site can be relieved by using ice packs. You will be advised to resume your normal activity on the next day after ESI. You may have to go to your doctor for a follow-up visit after a week of the procedure.
The risks associated with ESI include bleeding, infection, allergic reaction and nerve damage. The steroid medication used in ESI might have some side effects such as weight gain, hot flashes, mood swings, high blood sugar levels and sleeplessness.