Epidural Steroid Injection

Picture of a disc herniation compressing the spinal nerve root

An epidural steroid injection (ESI injection) is a common procedure to treat spinal nerve irritation that is most often caused by tissues next to the nerve pressing against it. The beginning of the nerve (nerve root) may be irritated by a bulging intervertebral disc, disc contents ("ruptured disc"), or bone spur, directly touching the spinal nerve.

An epidural steroid injection is used to relieve pain and inflammation in the spine. It is commonly used to treat conditions like sciatica, herniated discs, and spinal stenosis. The procedure involves injecting a combination of corticosteroids (powerful anti-inflammatory medications) and a local anesthetic into the space around the spinal cord, known as the epidural space.

When a disc in the spine bulges out of its normal position, it can press on nearby nerves, causing pain, numbness, or weakness. A bulging disc epidural steroid injection specifically targets this issue. The steroid helps reduce the inflammation around the bulging disc, which can relieve the pressure on the nerves and decrease pain. This treatment is often used when other methods such as physical therapy or medications have not provided enough relief.

An epidural steroid injection works to reduce inflammation surrounding the nerves, which can help relieve pain and discomfort. The injection's effects can continue for a few days to several months, depending on the individual and their condition.

It is crucial to note that, while epidural steroid injections can give significant pain relief for many patients, they are usually part of a broader treatment plan that includes physical therapy, exercise, and other pain management strategies.

Epidural steroid injections are typically administered by doctors who specialize in pain management and spine care. They include:

• Pain management specialists: These doctors focus specifically on diagnosing and treating various types of pain. They often have a background in anesthesiology or physical medicine and rehabilitation, with additional training in pain management techniques.
• Anesthesiologists: While many people associate anesthesiologists with operating room procedures, some specialize in pain management and are highly skilled in performing epidural injections.
• Physiatrists (physical medicine and rehabilitation physicians): These doctors specialize in treating a wide range of musculoskeletal conditions and are often involved in nonsurgical spine care, including epidural injections.
• Interventional radiologists: These specialists use imaging techniques to guide minimally invasive procedures, including epidural steroid injections.
• Neurologists: Some neurologists, particularly those who specialize in interventional pain management, may perform epidural steroid injections.
• Neurosurgeons: Similar to orthopedic surgeons, neurosurgeons who focus on spine care may perform these injections.
• Orthopedic surgeons: Particularly those who specialize in spine surgery may offer epidural steroid injections as part of their nonsurgical treatment options.

It is important to note that regardless of their primary specialty, doctors who perform epidural steroid injections undergo specific training in this procedure. They must be skilled in using imaging guidance (typically fluoroscopy) to ensure accurate needle placement and understand the intricate anatomy of the spine.

The epidural steroid injection procedure is quick and simple. While it is common for people to be concerned prior to the procedure, it is actually frequent to hear from patients afterward: "Is that all?"

The spinal cord rests in the spinal canal. The nerve roots branch out from the spinal cord at each level of a spinal vertebra (the bony building blocks of the spine). The cord is protected by cerebrospinal fluid (CSF), which serves as a shock absorber for the cord. The CSF is held in place by a membrane with several layers, one of which is called the dura, from the Greek for tough (think of "durable"). The Greek word "epi" means "outside of." So, the epidural space is outside of this tough membrane. During an epidural steroid injection, a needle and syringe are used to enter the epidural space and deposit small amounts of long-lasting steroids around the inflamed spinal nerve. A fluoroscope (a viewing instrument using X-rays) is used to visualize the local anatomy during the injection. The epidural steroid injection specifically targets the locally inflamed area and treats it with a maximal amount of steroids, thereby minimizing exposure of the rest of the body to the steroids.

Step-by-step procedure for administering an epidural steroid injection:

• Preparation: To prepare for an epidural steroid injection, you will be positioned based on the injection site. For lower back injections, you will lie face down; for neck injections, you will be seated. The area around the injection site is cleaned with an antiseptic solution to prevent infection. A local anesthetic is administered to numb the skin and surrounding tissues, minimizing discomfort during the procedure.
• Needle positioning: Using fluoroscopy, a real-time X-ray imaging technique, the doctor guides a thin needle into the epidural space — the area around the spinal cord where nerves are located. You may feel pressure or slight discomfort, but it should not be intense.
• Medication injection: Once the needle is correctly positioned, the doctor injects a combination of corticosteroids (to reduce inflammation) and a local anesthetic (for immediate pain relief) into the epidural space. The medication spreads to target the inflamed nerves.
• Monitoring and aftercare: Post-injection, you will be monitored briefly to check for any immediate adverse reactions. Most patients can return home the same day. Rest for the remainder of the day may be recommended, but normal activities can usually be resumed the following day.
• Follow-up: The full effects of the injection may take several days to become apparent. Some individuals experience immediate relief, while others see gradual improvement. A follow-up appointment may be scheduled to assess progress and determine if additional injections or treatments are necessary.

The procedure is typically quick and performed in an outpatient setting, so an overnight hospital stay is not required.

Epidural steroid injections are used to treat various conditions that cause pain and inflammation in the spine and surrounding nerves.  They 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 lower 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.

An epidural steroid injection may be used in the following conditions:

• Sciatica: This is a common reason for epidural steroid injections. Sciatica causes pain radiating from the lower back down one or both legs, often due to compression of a nerve root.
• Herniated or bulging discs: When a spinal disc protrudes and presses on nearby nerves, it can result in significant pain. Injections can help reduce inflammation around the affected disc.
• Spinal stenosis: This condition involves narrowing of the spinal canal, which can compress nerves. Injections can alleviate swelling and provide pain relief.
• Degenerative disc disease: As spinal discs degenerate with age, they can lead to pain and inflammation. Injections may help manage these symptoms.
• Chronic back pain: For persistent back pain not relieved by other treatments, epidural injections might be considered.
• Radiculopathy: This term describes pain, numbness, or weakness along the path of a spinal nerve. Injections can reduce inflammation causing these symptoms.
• Failed back surgery syndrome: Patients who continue to experience pain after spine surgery may benefit from epidural injections.
• Spondylolisthesis: In this condition, one vertebra slips over another, potentially compressing nerves and causing pain that may be treated with injections.
• Acute injuries: In some cases, epidural injections might be used to manage pain from acute back injuries, in conjunction with other treatments.

Epidural steroid injection side effects include elevation of blood sugar (glucose), insomnia, bleeding into the spinal canal, and rarely, bacterial or fungal infection in the spinal canal.

Common side effects:

• Pain at the injection site: Just like any other injection, an epidural steroid injection can cause mild soreness or discomfort at the injection site. It usually resolves within a few days.
• Temporary numbness or weakness: You may experience temporary numbness or weakness in the limbs, depending on the injection site. This effect is typically short-lived and resolves within hours.
• Headache: Some patients may develop a headache if the needle inadvertently punctures the spinal dura mater, leading to a post-dural puncture headache. Rest and hydration often help alleviate this type of headache.
• Flushing or facial redness: A feeling of warmth or redness in the face and chest may occur and generally subsides within a day.
• Insomnia: The steroid medication may cause difficulty sleeping for a few days after the injection.

Less common but more serious complications:

• Infection: Although rare, there is a risk of infection at the injection site. Serious infections, such as epidural abscesses, are very uncommon but require immediate medical attention.
• Bleeding: There is a risk of bleeding, especially in patients with bleeding disorders or those on blood thinners. In rare cases, this bleeding can form a hematoma, potentially compressing the spinal cord or nerves.
• Nerve damage: If the needle inadvertently damages a nerve, it may cause acute or, in rare cases, permanent nerve damage, resulting in pain, numbness, or weakness.
• Allergic reactions: Some patients may experience an allergic reaction to the medication, leading to irritation, redness, or, more severely, difficulty breathing.
• Arachnoiditis: A very rare but serious condition in which the outer layer of the spinal cord becomes inflamed, causing chronic pain and neurological problems.
• Increased blood sugar levels: The steroids may temporarily raise blood sugar levels, particularly in individuals with diabetes. This effect is usually temporary but should be monitored.
• Bone density loss (osteoporosis): Repeated use of steroid injections over time may weaken bones and lead to osteoporosis. This risk increases with frequent or prolonged use.

While the risk of serious complications from an epidural steroid injection is low, it’s important to discuss these potential side effects with your health care provider to ensure that the benefits of the procedure outweigh the risks in your specific case.

Recovery from an epidural steroid injection is typically within hours of the injection. If an anesthetic is administered with the steroid, there can be hours of residual numbness of the nerves that were anesthetized. However, it should subside as the anesthetic wears off.

Immediately after injection:

• Expect moderate discomfort or soreness at the injection site.
• Temporary numbness or weakness in the legs is common but resolves within a few hours.
• Rest for the remainder of the day and avoid strenuous activities or heavy lifting.

First 24 to 72 hours:

• Many patients can resume normal activities, including work, the day after the injection if they feel up to it.
• Pain reduction may be gradual, with full benefits of the steroid taking days to weeks to manifest.

Full recovery:

• Full recovery from the injection typically occurs within a few days, with soreness and temporary side effects resolving.
• Pain relief duration varies; some may experience relief for weeks, while others may benefit for several months. Additional injections may be necessary as part of an ongoing treatment plan.

• What is an epidural steroid injection used for? Epidural steroid injections are used to relieve chronic pain and inflammation in the spine, particularly for ruptured discs, sciatica, spinal stenosis, and even during childbirth.
• How long do steroid epidural injections last? The pain-relieving effect of an epidural steroid injection may last for a few days to several months, depending on the individual and the condition being treated.
• What are the dangers of epidural steroid injection? Though epidural steroid injections are generally safe, there is a risk of developing infection, bleeding from the injection site, and injury to the nerve in rare cases.
• What is the dark side of the epidural steroid injection? The "dark side" or potential risks of epidural steroid injections include rare but serious complications, such as low blood pressure, infection, bleeding, nerve damage, spinal cord injury, and temporary loss of control over bladder and bowel function. However, these are extremely rare complications of epidural steroid injections.
• Is an epidural steroid injection painful? An epidural steroid injection may cause slight discomfort or pain. To minimize this, the area is typically numbed before the injection, so most patients do not experience pain. However, some may feel brief pressure initially.