Lumbar Epidural is performed for chronic pain, mostly radiating into the lower extremities. The chronic lumbar pain also called as sciatica or radiculopathy may or may not be associated with tingling, numbness as well as weakness of the lower extremities. The procedure is performed either for diagnostic purpose or therapeutic reason.
Diagnostic injection is performed to evaluate the cause of the pain. There are 5 lumbar nerves which are passing into the lower extremities. The pain may come from any one of the 5 or it may involve more than 1 lumbar nerve. Reason diagnostic injection is performed is to find out the level of the nerve which is pinched either by disc herniation or bulge disc and to perform the injection so pain is relieved and the cause of the pain is possibly treated with surgical treatment.
Therapeutic injection is performed if the patient is not a candidate for surgery or any other treatment and not responding to oral pain medications and any other treatments. Therapeutic injection are performed multiple times and repeated every 3 to 6 months.
Diagnostic injection or therapeutic injection of the procedure transforaminal injection is done in the operating room. The surgical center provides the sterilized environment which is important to prevent any infection in the epidural space.
Patient is brought in the operating room and asked to lie in prone position which is on the stomach. The pillow is kept underneath the patient’s stomach or over the operating bed. X-ray is used to identify lumbar vertebrae. The diagnostic injection is performed at the selected nerve either lumbar nerve 1, 2, 3, 4, or 5. The level requested for the diagnostic injection depends on findings of the clinical examination, MRI studies, CAT scan and EMG examinations.
If the patient is scheduled for diagnostic injection, then 1 or 2 level injections are performed the same time. If the patient is scheduled for therapeutic injection, then up to 3 levels of injections are performed the same time.
Once the patient is in the operating room, on the bed in prone position, the x-ray is used to identify the level of the foramina where the injection is to be performed. The local anesthesia is used to anesthetize the skin as well as subcutaneous tissue. AP view of the x-ray, lateral or oblique view of the x-ray is used for the procedure. Once the foramen is observed using the x-ray, the needle entry point is marked with marking pen. The skin over the needle entry point is anesthetized with local anesthesia. Local anesthesia used for skin and subcutaneous tissue is 1% Lidocaine. The amount used is 1 to 2 cc. The medication is injected using 25 gauge needle. After local anesthesia, the needle is passed under the x-ray guidelines in to the foramina from oblique side. The needle is very carefully introduced into the foramina. Sometimes patient may feel a parasthesia which means patient may have a severe pain passing through the nerve into the leg if the needle is touching the nerve. In that case, carefully nerves have to be placed on the side of the nerve. The needle placement is extremely important to prevent any complications. X-ray guideline and frequent change of the view of the x-ray either AP, lateral, or oblique is necessary to prevent the passing of the needle into the epidural space or into the spinal space. Once the needle is placed into the foramina, the dye is injected. The dye spread along the nerve is observed. The dye will spread along the nerve and exterior direction as well as into the spinal canal. After confirmation of the satisfactory placement of the spinal needle, the procedure is performed by injecting the medications. Medications injected are normal saline, local anesthesia, and cortisone injection. Cortisone injection used is either Depo-Medrol or Kenalog while local anesthesia used is 2% Lidocaine or Bupivacaine. The local anesthesia which is used should not have any preservative. After the procedure, needle is removed, patient is transferred to the recovery room and patient is observed for any further complication. Patient is discharged home if there is no complication. Patient is evaluated following the procedure as well as first visit after the injection in the office.