Epidural steroid injections have been used in the field of medicine for over 70 years to provide anesthesia during surgeries and in childbirth, and are a well established treatment of pain caused by different spinal conditions.
These injections typically deposit steroids and/or other medications in the epidural space of the spine to alleviate pain. The epidural space contains nerve roots, spinal cord, blood vessels, and fat; and surrounds the dura, a sac around the spinal cord.
Epidural steroid injections may be given in the cervical , thoracic, lumbar or sacral regions of the spine.
How do Epidural Steroid Injections Work?
Epidural injections can be used to inject steroids , anesthetic, steroids mixed with an anesthetic medication and/or saline, or other solutions such as Platelet Lysate. When these solutions are injected into the epidural space the goal is to:
- Bathe local nerve roots, spinal cord, degenerative disc or surrounding tissues to decrease localized inflammation due to mechanical or chemical irritation.
- Reducing the activity of the immune system to decrease the production of inflammatory cells in the body.
What Conditions do Epidural Steroid Injections Treat?
Epidural steroid injections may help relieve pain stemming from conditions such as spinal stenosis, foraminal stenosis, disc herniation that can result in nerve root irritation also known as radiculitis or degenerative disc disease. An epidural injection can be performed in the neck, mid-back or lower back/buttocks.
The injections can be used to treat pain in each of these three regions or pain that radiates out from these areas into the arms and legs and less frequently into the chest/thorax.
How are Epidural Steroid Injections Performed?
There are different ways or approaches to perform an epidural steroid injection depending upon the area of the spine being treated and the target structures.
- Transforaminal injection—the needle is inserted into the epidural space through the hole (intervertebral foramen) on the side of the spinal canal where the nerve root exits. A space above the spinal nerve as it exits the neuroforamen called the safe triangle is the region where the needle is usually passed to reach the epidural space. This technique is called the supraneural approach.
- Interlaminar injection—the needle is inserted into the space between adjacent vertebral laminae (posterior wall of the vertebra) to reach the epidural space.
- Caudal injection—the needle is placed into the sacral area below the lumbar spine through an opening called the sacral hiatus.
These procedures should always be performed using Fluoroscopy, a motion X ray guidance to ensure accuracy and safety.
Success Rates of Epidural Steroid Injections
Several studies have proven the efficacy of epidural steroid injections throughout the spine. Studies show that:
- In the cervical spine, 54% to 80% of patients reported significant improvement in pain and functional outcome from 6 months to 2 years (with a total of 3 to 6 injections given during this period).
- In the lumbar spine, 53% to 56% of patients reported significant improvement in pain and functional outcome up to 1 year (a total of 3 to 4 injections were given during this period)
The effectiveness of epidural steroid injections is improved when additional modalities including Physical Therapy, Acupuncture, and massage are also employed.
Risks and Complications of Epidural Steroid Injections
Epidural steroid injections are commonly performed procedures and are generally safe and well tolerated when performed by trained providers specializing in Anesthesiology or Physical Medicine and Rehabilitation.
Although rare, some serious risks associated with epidural steroid injections include infection, nerve damage, bleeding, dural puncture (cerebrospinal fluid leak), and/or damage to the spinal cord.
Possible Side Effects of Epidural Steroid Injections
Side effects can occur and are usually mild after an epidural steroid injection. Common side effects include:
- Nausea
- Headache
- Dizziness
- Flushing of the face (redness and a feeling of warmth)
- Insomnia
Epidural Steroid injections are one of many non surgical tools that can be effective in reducing pain and improving function in many spinal conditions.
Michelle Hall
PA-CPhysician Assistant
