Overview of Epidural Steroid Injections
Epidural steroid injection (ESI) is a procedure used to relieve neck, arm, back, and leg pain related to inflamed spinal nerves. This procedure is performed to relieve the pain associated with spondylolysis, spinal stenosis, and disc herniation.
Medications are injected around the spinal nerves through the epidural space, which is the area between the protective covering of the spinal cord and vertebrae. ESI effects are often temporary, and the pain relief may last for several days, weeks, or even months. The goal of an epidural spinal injection is to reduce pain so the patient can resume normal activities and utilize a physical therapy program.
The medication that is injected into the epidural space is a long-lasting corticosteroid, such as betamethasone or triamcinolone, along with an anesthetic numbing agent, such as bupivacaine or lidocaine. The medications are injected into the epidural space of the spine, which is the region between the spinal cord covering (dura) and the bony vertebrae. That area is filled with tiny blood vessels and fat. Cortisone injections reduce the inflammation in the discs, but do not correct a herniated disc.
Candidates for Epidural Steroid Injections
Any patient who has pain of the arm, neck, low back, or leg could benefit from ESI. Also, a steroid injection treats the following conditions:
- Spondylolisthesis – A weakness or fracture between the upper and lower facets of the vertebra. If that bone slips forward and compresses the nerve roots, it is called spondylolisthesis.
- Spondylolysis – This is a narrowing of the spinal canal and nerve root canal that causes back and leg pain with walking.
- Degenerative disc – This is aging of the intervertebral disc, which results in collapse of the disc space, growth of bone spurs, and tears in the annulus.
- Herniated disc – When the gel-like material in the disc bulges/ruptures out through the wall, pain, irritation, and swelling occurs. The herniated disc is when the material squeezes out and comes in contact with the spinal nerve.
- Sciatica – Pain that occurs along the sciatic nerve and radiates down the buttocks and legs. This is usually due to compression of the fifth lumbar or first sacral spinal nerve.
- Inflammatory conditions – ESI is helpful for patients who have inflammatory conditions, such as strains and sprains. Many patients take the epidural so they can continue with physical therapy.
Before the Procedure
An epidural cannot be performed on a person who has an infection, is pregnant, or has bleeding problems. It is not recommended for anyone with poorly controlled diabetes because it can result in elevated sugar levels. Due to the fact that blood pressure can elevate also, patients with hypertension cannot have this treatment. The procedure is administered by physiatrists, radiologists, anesthesiologists, neurologists, and surgeons.
Before the procedure, the doctor has to take a medical history and perform a physical examination. Any patient who has been taking a blood thinner cannot have an ESI. These medicines include Coumadin, Plavix, Heparin, Ticlid, Orgaran, Fragmin, Lovenox, aspirin, and Innohep. Be sure to discuss these medications with your doctor, including the one who prescribed them to you.
The day of the procedure, you should arrive 15 minutes before the scheduled appointment and have something light to eat that morning. Make arrangements to have someone drive you to and from the office or outpatient center on the day you have the ESI.
On the day of the procedure, the doctor will inject medication close to the site of pain using a translaminar or transforaminal injection. The type of shot he chooses depends on the patient’s condition and which procedure is best for that disorder. Most doctors use a fluoroscopy (x-ray) to guide the needle into the epidural space. Total time for the ESI is around 20 to 30 minutes, followed by a brief recover period.
- Step 1: Prepare the patient – The patient will remain awake during the epidural steroid injection, but a sedative is often given to ease anxiety. The patient receives a local anesthetic to numb the skin, and when IV sedation is used, the heart rate, blood pressure, and breathing is monitored.
- Step 2: Insert the needle – The doctor will direct a hollow needle through the skin into the epidural space. Fluoroscopy is done to ensure that the steroid medicine is delivered close to the nerve root. Expect some discomfort at this time, such as a sensation of pressure.
- Step 3: Deliver the medication – The doctor will use one of three ways to deliver the epidural steroid injection: translaminar, transforaminal, or caudal approach.
After the Procedure
Most patients walk around after the procedure, after being briefly monitored. Usually, patients resume full activity the next day, and soreness at the injection site is expected. The doctor will want to follow up with the patient in a week to make sure symptoms are relieved. Many patients have instant pain relief with the epidural steroid injection. For those who do not have relief, the doctor will perform another injection, usually in two weeks. The benefits of ESI are only short term, meaning they could last for weeks or months.
The Risks and Side Effects
There are few risks to the ESI, but they do exist. The potential risk associated with ESI include dural puncture, infection, bleeding, allergic reaction, and nerve damage. Corticosteroid side effects include water retention, weight gain, flushing, mood swings, insomnia, elevated blood pressure, and elevated blood sugar. Certain people should consult a physician before being treated with an ESI, such as those with chronic health conditions (diabetes, heart disease, rheumatoid arthritis), and those who are on blood thinners.
Botwin KP, Gruber RD, Bouchlas CG, et al. Fluoroscopically guided lumbar transformational epidural steroid injections in degenerative lumbar stenosis: an outcome study. Am J Phys Med Rehabil. Dec 2002;81.
Buenaventura RM, Datta S, Abdi S, Smith HS. Systematic review of therapeutic lumbar transforaminal epidural steroid injections. Pain Physician. Jan-Feb 2009;12(1):233-51.
Vad VB, Bhat AL, Lutz GE, et al. Transforaminal epidural steroid injections in lumbosacral radiculopathy: a prospective randomized study. Spine. Jan 1 2002;27(1):11-6.