An epidural steroid injection (ESI) is a procedure to inject steroid medicine into the epidural space. The epidural space covers the spinal cord and is between your spinal cord and vertebrae.
Steroids reduce inflammation and fluid buildup in your spine that may be causing pain. You may be given pain medicine along with the steroids.
When is it used?
An epidural steroid injection is performed to help reduce the inflammation and pain associated with nerve root compression. Nerve roots can get compressed by a herniated disc, spinal stenosis, and bone spurs. Inflammation occurs when the nerve is compressed, which can lead to pain, numbness, tingling or weakness along the course of the nerve. This is called radiculopathy. The goal of the epidural steroid injection is to help lessen the inflammation of the nerve root.
The location along the spinal column is one way to describe the type of epidural steroid injections.
- Injections in the neck are called cervical epidural injections,
- Injections in the middle back are thoracic epidural injections
- Injections in the low back are called lumbar epidural injections.
They can also be described according to the path of the needle.
Most epidural steroid injections are placed between two lamina, known as interlaminar epidural steroid injections. The two lamina are part of the vertebral bone (body) on either side of the spinous process—the bony part that sticks out of your spine and can be felt as the back bone. The spinal cord is not shown here but would becoming through the opening called the vertebral foramen from the base of the skull down to the tailbone. Another type of injection is a transforaminal steroid injection.