An epidural steroid injection is performed to help reduce the inflammation and pain associated with nerve root compression. Nerve roots can be compressed by a herniated disc, spinal stenosis, and bone spurs. When the nerve is compressed it becomes inflamed. This 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 epidural space is located above the outer layer surrounding the spinal cord and nerve roots. An epidural steroid injection goes into the epidural space, directly over the compressed nerve root.
There are several types of epidural steroid injections. They can be described according to the location they are given. Injections in the neck are called cervical epidural injections, while injections in the middle back are thoracic epidural injections, and 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 the lamina, known as interlaminar epidural steroid injections. The lamina is portions of the bones on the back side of the spine that are arranged like shingles. The needle is aimed upwards toward the head and passes between two adjacent laminae. Another type of injection is a transforaminal steroid injection. In this case, the needle passes along the course of the nerve and enters the spine from a more diagonal direction.
Patients with several common conditions - including a lumbar disc herniation, degenerative disc disease, and lumbar spinal stenosis - may benefit from an epidural injection. For these and other conditions that can cause acute or chronic pain, an epidural steroid injection may be an effective non-surgical treatment option.