An epidural steroid injection (ESI) is used to treat inflammation associated with neck related arm pain, or low back related leg pain.
The pain is usually caused by a narrowing of the passages where the spinal nerves pass down or out of the spine.
A narrowing spinal passage can occur as a result of bone spurs, disc herniations, joint cysts, abnormal alignment of the vertebrae, or thickening of the ligaments in the spine.
Benefits of an ESI
During an ESI treatment, cortisone is injected into the epidural space, which is the space that surrounds the spinal sac and cushions the nerves and spinal cord. An ESI treatment can help alleviate pain and inflammation in and around the spinal nerve roots as well as around damaged nerves.
An ESI procedure can be performed to alleviate pain caused by:
- Post-operative “failed back” surgery syndromes
- Bone spurs
- Injuries to spinal nerves, vertebrae and surrounding tissue
- Spinal stenosis (narrowing of the spinal canal)
- Herniated or bulging discs
Side Effects of an ESI
After an ESI procedure, patients may experience:
- Skin thinning
- Loss of color in the skin
- Insomnia
- Moodiness
- High blood sugar
- Facial flushing
The greater the number of steroid injections, the higher the risk of experiencing these side effects.
What to Expect During an ESI
An ESI can be performed using one of three different methods of injecting the steroid into the epidural space: caudal, interlaminar and transforaminal. Whichever method is chosen, a thin needle will be positioned using fluoroscopic (or X-ray) guidance and contrast dye will be used to make sure the medication reaches the intended area. Local anesthetic may be added to provide temporary pain relief.
During an interlaminar ESI, also known as an epidural injection, the steroid is injected into the back of the epidural space and covers a wide area.
During a caudal ESI, the steroid injection is delivered to the sacral hiatus (a small opening just above the tailbone) and targets the very bottom of the epidural space. In both approaches, the steroid spreads over several spinal segments and affects both sides of the spinal canal.
During a transforaminal ESI, also known as a nerve block, the steroid is injected alongside the nerve exiting the spine and the medication is delivered into the nerve sleeve. The medication reaches the epidural space through the sleeve. This method of ESI is useful for treating one segment or one side of the back.
Patients may feel tingling or pressure when the injection is performed. If the swelling is extensive, patients may experience a burning sensation or mild discomfort as the epidural reaches the epidural space. Once the procedure is finished, patients will rest for up to an hour and a nurse or technologist will check to make sure they are not experiencing any unfavorable reactions before leaving the facility.
Recovering from an ESI
All ESI procedures are performed on an outpatient basis and patients typically return to normal activities the following day. Patients may request mild sedation, but most only require local anesthetic on the skin.