An epidural steroid injection places this powerful anti-inflammatory medication directly around the spinal nerves. Traditionally epidural injections were administered without any special equipment, by inserting the needle by feel in the area around the spinal nerves. More recently epidural injections have been administered with the aid of imaging tools to allow your physician to see the needle going to the proper location. Either real-time x-ray called fluoroscopy, or CT scan can be used to 'watch' the needle deliver the medication to the proper location.
Epidural steroid injections are generally very safe, but there are some rare potential complications. One of the most common risks is for the needle to go too deep and cause a hole in the dura, the tissue that surrounds the spinal cord and nerve roots. When this occurs spinal fluid can leak out through the hole and cause a headache . This headache can be treated with bedrest, or with a blood patch. A blood patch involves drawing some blood from the vein and the injecting it over the hole in the dura. The blood forms a seal over the hole and prevents any further fluid from leaking out.
Epidural steroid injections are most commonly used in situations of radicular pain, which is a radiating pain that is transmitted away from the spine by an irritated spinal nerve. Irritation of a spinal nerve in the low back ( lumbar radiculopathy ), such as from lumbar spinal stenosis , cervical spinal stenosis, herniated disc , and foraminal encroachment, causes back pain that goes down the leg. Epidural injection is also used as a minimally invasive procedure to treat nerve compression in the neck (cervical spine), referred to as cervical radiculopathy , which causes pain.