An epidural steroid injection (ESI) is a minimally invasive procedure that can help relieve neck, arm, back, and leg pain caused by inflamed spinal nerves. ESI may be performed to relieve pain caused by spinal stenosis, spondylolysis, or disc herniation. Medicines are delivered to the spinal nerve through the epidural space, the area between the protective covering of the spinal cord and vertebrae. The effects of ESI pain relief may last for several days or even years. The goal is to reduce pain so that you may resume normal activities and a physical therapy program.
An epidural steroid injection includes both a long-lasting corticosteroid (e.g., dexamethasone, triamcinolone, betamethasone) and an anesthetic numbing agent (e.g., lidocaine, bupivacaine). The drugs are delivered into the epidural space of the spine, which is the area between the protective covering (dura) of the spinal cord and the bony vertebrae. This area is filled with fat and small blood vessels.
Patients with pain in the neck, arm, low back, or leg (sciatica) may benefit from ESI. Specifically, those with the following conditions:
- Spinal Stenosis: A narrowing of the spinal canal and nerve root canal can cause back and leg pain, especially when walking.
- Spondylolysis: A weakness or fracture between the upper and lower facets of a vertebra. If the vertebra slips forward (spondylolisthesis), it can compress the nerve roots causing pain.
- Disc Herniation: The gel-like material within the disc can bulge or rupture through a weak area in the surrounding wall (annulus). Irritation, pain, and swelling occur when this material squeezes out and comes in contact with a spinal nerve.
- Degenerative Discs: A breakdown or aging of the intervertebral disc causing collapse of the disc space, tears in the annulus, and growth of bone spurs.
- Radiculitis: Pain that courses along the sciatic nerve in the buttocks and down the legs. It is usually caused by compression of the 5th lumbar or 1st sacral spinal nerve.
ESI has proven helpful for some patients in the treatment of the above painful inflammatory conditions. ESI can also help determine whether surgery might be beneficial for pain associated with a herniated disc. When symptoms interfere with rehabilitative exercises, epidurals can ease the pain enough so that patients can continue their physical therapy.
ESI should NOT be performed on people who have an infection, are pregnant, or have bleeding problems. It may slightly elevate the blood sugar levels in patients with diabetes, typically for less than 24 hours. It may also temporarily elevate blood pressure.
The doctor who will perform the injection reviews your medical history and previous imaging studies to plan the best approach for the injections. Be prepared to ask any questions you may have at this appointment.
Patients who take take blood thinner medication (Coumadin, Heparin, Plavix, Ticlid, Fragmin, Orgaran, Lovenox, Innohep, high-dose aspirin) may need to stop taking it 3 to 5 days before the ESI. Discuss any medications with your doctors, including the one who prescribed them and the doctor who will perform the injection. If you take Coumadin, a blood draw will be done at least 2 hours prior to the procedure to test your blood clotting (PT-INR test).
If you think you may be pregnant or are trying to get pregnant, please tell the doctor. Fluoroscopy x-rays used during the procedure may be harmful to the fetus.
The goal is to inject the medication as close to the pain site as possible, using either a translaminar or transforaminal injection. The right type of injection depends on your condition and which procedure will likely produce the best results and the least discomfort or side effects. Studies have shown that use of fluoroscopy (X-ray) to guide the needle into the epidural space is more effective than when the ESI is performed without fluoroscopy. The procedure usually takes 15-30 minutes and is followed by a recovery period.