Epidural steroid injections place corticosteroid medication directly around a pinched nerve as it exits the spine within the epidural space. The epidural space is located where the bones and discs of the spine surround the nerves and spinal cord. This is the space into which disc tissue can herniate and cause pressure and inflammation around spinal nerves.
Epidural steroid injections are commonly used to treat back pain caused by a herniated disc (slipped disc), lumbar or cervical radiculopathy, spinal stenosis or sciatica. Corticosteroids are strong anti-inflammatory medications and, when placed into the epidural space, can significantly reduce inflammation around an irritated nerve that is causing back and leg pain and discomfort.
The most commonly used steroids in epidural injections are dexamethasone, betamethasone, methylprednisolone, and triamcinolone. The choice of agent and dose is based on patient factors, response to prior injections, the region of the spine being injected, and the epidural approach.
Patients with several common conditions – including lumbar disc herniation, degenerative disc disease, lumbar radiculopathy, sciatica, lumbar spinal stenosis, postherpetic neuralgia and facet/synovial cysts – may benefit from an epidural injection. An epidural steroid injection may be an effective nonsurgical treatment in itself or may aid in surgical planning.
Epidural steroid injections work by delivering a potent anti-inflammatory to the site of nerve impingement in the spine. Injected medications may include steroids, local anesthetics, and saline, and they can vary in volume and concentration on an individual basis. While epidural injections for other applications may not require image guidance, epidural steroid injections for pain management are routinely performed with fluoroscopic or X-ray guidance to ensure correct, effective, and safe deposition of the injected medications. In select cases, CT or ultrasound guidance may be used as an alternative if indicated.
Epidural steroid injections in the cervical and thoracic spine can be used to treat cervical or thoracic herniated discs, radiculopathy, degenerative disc disease, or spinal stenosis. In the cervical region (neck), these conditions cause pain and neuropathies that radiate to the arm and hand. In the thoracic region (upper back and chest), pain can radiate to the ribs or flank. Injections may be done using an interlaminar or transforaminal technique as described below.
Three routes may be used for epidural injections in the lumbosacral spine (the vertebrae in the lumbar spine and sacrum of the lower back)
Your physician will choose which method is right for you based on your diagnosis and if you have had any prior spine surgeries.
Epidural steroid injections are recommended to be administered up to three to six times per year. In the case of a new disc herniation, injections may be only weeks apart with a goal of quick and complete resolution of symptoms. For chronic conditions, three to six months or more between injections is common.
Epidural steroid injections can help resolve pain permanently in patients with a new disc herniation who respond favorably. For patients with chronic pain or recurrent disc herniations, the desired duration of effect is three to six months or more.
The risks in any procedure involving a needle include bleeding, infection and nerve damage. When performed properly, the risk of any of these is exceedingly low and usually outweighed by the potential benefit of the procedure.
Some contraindications for performing epidural steroid injections include:
Risks and benefits of repeated epidural steroid injections should be weighed on a case-by-case basis for patients who have or are at-risk for osteoporosis, as some evidence suggests repeated steroid injections can accelerate bone loss.
Common side effects include mild injection site pain, temporary worsening of usual pain, flushing, insomnia, or increased blood sugar. These are usually self-limited and resolve within one to three days. A less common side effect is headache.
Your doctor will give you specific instructions and these will vary by facility and type of epidural (lumbar, thoracic or cervical). Because the procedure is usually performed with local anesthetic rather than sedation, fasting guidelines are not overly prohibitive.
A local anesthetic is injected into the skin, numbing the area where the epidural needle is then placed. Patients may experience mild discomfort but should not experience severe pain during the procedure.
The procedure can last anywhere from 10 to 20 minutes and requires the patient to lie prone, if possible, to allow for X-ray guidance (fluoroscopy). After the procedure, you can sit, stand, and walk as usual after a short period of monitoring.
Epidural steroid injections at HSS are performed by several types of doctors – pain management physicians, physiatrists and interventional radiologists – all of whom are trained to safely perform this procedure, often with additional subspecialty fellowship training.