An epidural steroid injection (ESI) is a minimally invasive course of action that can help alleviate  leg, back, arm, and neck pain caused by inflamed spinal nerves. ESIs may be carried out to relieve pain produced by spinal stenosis, or disc herniation. Medicines are dispensed to the spinal nerve through the epidural space, the region between the protective covering of the spinal cord and vertebrae. The effects of ESI tend to be brief. The objective is to reduce pain so that you may continue normal activities and a physical therapy program.

An epidural steroid injection comprises of both a long-lasting corticosteroid (e.g., triamcinolone, betamethasone) and an anesthetic numbing agent (e.g., lidocaine, bupivacaine). The two 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.

Corticosteroid injections can reduce inflammation and can be effective when delivered directly into the painful area. Regrettably, the injection does not make a herniated disc smaller; it only works on the spinal nerves. This liberation from pain can last from days to years, permitting you to improve your spinal condition with an exercise program and/or physical therapy.
Patients with pain in the lower back, neck, leg or arm may benefit from ESI. Especially those with the following conditions:

  • Sciatica: 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.
  • Spinal stenosis: A tightening of the spinal canal and nerve root canal can cause back and leg pain, especially when walking.
  • Degenerative disc: A breakdown or aging of the intervertebral disc causing collapse of the disc space, tears in the annulus, and growth of bone spurs
  • Herniated disc: 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.
  • 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.

ESI has proven useful for many patients in the treatment of the above painful inflammatory conditions. ESI can also help establish whether surgery might be beneficial for pain linked with a herniated disc. When symptoms get in the way of rehabilitative exercises, an epidural can immediately deliver pain relief to patients, so that they can continue their physical therapy.

ESI should NOT be done on people who are pregnant, have bleeding problems, or have an infection. It may faintly elevate the blood sugar levels in patients with diabetes, usually for less than 24 hours. It may also briefly elevate blood pressure.