Epidural Steroid Injection (ESI)
Chronic pain syndromes are often successfully treated with Epidural Steroid Injections (ESI). The typical pain that is successfully treated by ESIs is called “radicular pain,” which refers to a weakened or irritated nerve root. It is also known as “Radiculitis.”
Radicular pain sends pain sensations from the spine through the nerves and feels like “traveling pain” often focused in the lower back (lumbar area) and down the leg, depending on where the irritated nerve root is located. Sometimes the irritated nerve root is located in the neck (Cervical area), so the pain radiates down the arm. In both cases, epidural injections can treat the nerve compression and relieve the pain.
Common conditions successfully treated by ESI include:
- Degenerative Disc Disease (Botwin 2007)
- Herniated Discs (Lin 2006)
- Spinal stenosis
ESI has been confirmed to reduce radicular pain and improve standing and walking in patients with Degenerative Lumbar Spinal Stenosis (Botwin 2007).
How Epidural Steroid Injection is Done
The epidural space is located in the dura mater, which is a strong fibrous material covering the spinal cord and brain. An epidural injection goes directly into the spine into the epidural space. The injection contains two types of medicine: a steroid and a local anesthetic. The steroid reduces inflammation and irritation while the anesthetic interrupts the pain-spasm cycle (Boswell 2007). The medicine can spread through the spine to reduce inflammation and irritation caused by irritated nerve roots. A typical epidural injection will last approximately 15 minutes.
For patients experiencing chronic pain, the relief is quick and dramatic. Most successful treatments allow patients to become active and resume their daily activities without pain.
Doctors tailor the amount of medicine in the injection as well as the location of the needle insertion, depending on where the pain is located and the number of nerve roots that need treatment. These decisions are made after a comprehensive examination and history to determine the cause of the pain.
There are three types of ESI injections a physician may choose for a patient:
- Intralaminar Injection: First the doctor anesthetizes the skin, and then inserts the needle in the midline of the back between the lamina of two vertebrae, directly posterior to the vertebrae. The steroid/anesthetic combination is injected into the epidural space in the midline and spreads to nerve roots along the spine. This treatment is commonly used for short-term relief and has limited success for long-term relief.
- Transforaminal Injection: First the doctor anesthetizes the skin, and then inserts the needle through the side of the vertebra above the opening for the nerve root. With this approach the medicine doesn’t travel as much, so it is considered a more focused approach to pain in a specific area. It is also effective when patients have scarring or other “foreign bodies” such as pins from surgeries, etc., that the physicians want to avoid with the medicine in the injection. Transforaminal injections work well for short-term pain relief and moderately well for long-term improvement for managing lumbar back pain (Manchikanti 2007).
- Caudal Injection: First the doctor anesthetizes the skin, and then inserts the needle to the epidural space by the patient’s tailbone. This technique allows for a catheter to be put in place to deliver larger volumes of steroid and anesthetic. The higher volume of medication gets to more nerve roots and inflamed areas all at once, and is usually used in areas of heavy scarring. Caudal ESIs are often combined with a procedure named Lysis of Adhesions or the Racz procedure, which is used to treat epidural scarring. This procedure works well for short-term pain relief and moderately well for long-term pain relief.
Benefits to Using ESI to Treat Chronic Pain
Epidural Steroid Injections are a routine and relatively painless treatment option. In a 2007, during a research trial to evaluate the usefulness of a cervical interlaminar ESI in patients with neck pain and cervical radiculopathy, 72% of patients experienced immediate pain relief (Kwon 2007). Sometimes, only moderate pain relief comes from the first injection, but only two weeks later another injection can be used.
Using multiple injections has been studied extensively and it has been concluded that therapy with multiple ESIs provides better control of chronic neck pain compared to the relief from a single injection (Pasqualucci 2007). Physicians will likely recommend multiple ESI treatments, often in sets of three.
The rapid relief of symptoms is the most commonly cited benefit to ESI treatment for chronic pain syndromes. Patients experience relief from pain almost immediately and are able to become active in their normal daily activities again.
Risks to Using ESI to Treat Chronic Pain
Epidural Steroid Injections are an appropriate, non-surgical treatment for many patients who suffer from back and neck pain. Though commonly performed all over the world, and very safe, there are risks associated with any medical procedure involving injections. Risks include bleeding, infection, post-dural puncture headache and nerve damage.
Other risks may be related more with the medicine than the procedure. Some side effects of the steroids may include weight gain, arthritis, elevated blood sugars, stomach ulcers, and transient decrease in immune system function. A patient’s physician should assess these risks before undergoing ESI treatment.
If patients have an allergy to any anesthetic, are on blood thinners, have an infection or are pregnant, they need to consult with their physician before undergoing ESI treatment.
Relief from ESI Treatments
Patients’ pain relief from ESI treatment will vary in duration and amount of relief. There are many factors including the overall health of the patient, and their activity level. Some ESI treatments will administer relief that lasts for years while others will only experience short-term relief. It is important to have future treatment options available in the event of short-term relief only from ESI.
The Department of Rehabilitation Medicine at the University of Washington conducted a study comparing the risks and effectiveness between surgery and lumbar ESI treatments. They concluded “when weighing the surgical alternatives and associated risk, cost and outcomes, lumbar epidural steroid injections are a reasonable non-surgical option in select patients.” (Young 2007)
- Fluoroscopically guided caudal epidural steroid injections in degenerative lumbar spine stenosis. Botwin K, Brown LA, Fishman M, Rao S. PMID: 17660853 [PubMed – in process]
- The use of lumbar epidural/transforaminal steroids for managing spinal disease. Young IA, Hyman GS, Packia-Raj LN, Cole AJ. PMID: 17426294 [PubMed – indexed for MEDLINE]
- The use of lumbar epidural/transforaminal steroids for managing spinal disease. J Am Acad Orthop Surg. 2007 Apr;15(4):228-38 Young IA, Hyman GS, Packia-Raj LN, Cole AJ
- Cervical epidural steroid injections for symptomatic disc herniations. J Spinal Disord Tech. 2006 May;19(3):183-6. Lin EL, Lieu V, Halevi L, Shamie AN, Wang JC
- Cervical interlaminar epidural steroid injection for neck pain and cervical radiculopathy: effect and prognostic factors. Skeletal Radiol. 2007 May;36(5):431-6. Epub 2007 Mar 6 Kwon JW, Lee JW, Kim SH, Choi JY, Yeom JS, Kim HJ, Kwack KS, Moon SG, Jun WS, Kang HS
- Epidural steroids in the management of chronic spinal pain: a systematic review. Pain Physician. 2007 Jan;10(1):185-212. Abdi S, Datta S, Trescot AM, Schultz DM, Adlaka R, Atluri SL, Smith HS, Manchikanti L.