How Epidural Steroid Injections Relieve Back Pain

An Educational Resource by Delaware Valley Pain & Spine Institute

Chronic back pain affects millions of Americans every year, impacting mobility, productivity, and quality of life. One common treatment option often recommended for nerve-related spinal pain is the epidural steroid injection (ESI). At Delaware Valley Pain & Spine Institute, with offices in Chafont, PA, Marlton, NJ, and Trevose, PA, patients frequently inquire about how these injections work and whether they are a suitable treatment. This blog offers a detailed, patient-friendly explanation of what epidural steroid injections are, how they function, and what to expect before, during, and after the procedure.

Understanding the Source of Back Pain

To grasp how epidural steroid injections work, it’s important to first understand what causes back pain, particularly when nerves are involved. The spinal cord runs through the spinal canal and is protected by vertebrae and cushioned by intervertebral discs. Nerve roots exit the spine at various levels, branching out to the limbs and other parts of the body. When the spinal structures become inflamed or compressed—due to a herniated disc, spinal stenosis, or degenerative disc disease—the nearby nerves can become irritated, leading to pain, numbness, or weakness.

Inflammation plays a central role in this process. When a disc herniates or the spinal canal narrows, it can compress a nerve root and trigger the release of inflammatory chemicals. These substances irritate the nerve, causing pain that may radiate down the arms or legs, depending on the location of the problem. Epidural steroid injections target this inflammation directly to provide relief.

What Is an Epidural Steroid Injection?

An epidural steroid injection is a minimally invasive procedure that delivers corticosteroid medication directly into the epidural space surrounding the spinal cord and nerve roots. The goal is to reduce inflammation, relieve pain, and improve function. The injection typically contains a corticosteroid (like dexamethasone or triamcinolone) to decrease swelling, and a local anesthetic (such as lidocaine) to provide immediate but temporary relief.

This treatment is commonly used to address conditions such as lumbar radiculopathy (sciatica), cervical radiculopathy, spinal stenosis, and herniated discs. While ESIs are not a permanent fix, they can offer significant pain relief for weeks or months, allowing patients to participate in physical therapy or return to normal activities more comfortably.

The term “epidural” refers to the area just outside the dura mater, the outermost membrane covering the spinal cord. Administering medication here allows it to coat the irritated nerve roots directly, targeting the inflammation with precision.

How the Procedure Is Performed

The procedure is generally performed in an outpatient setting under the guidance of fluoroscopy (real-time X-ray imaging) to ensure accurate needle placement. It typically takes less than 30 minutes and requires only local anesthesia or mild sedation.

Step-by-Step Overview:

• Positioning: The patient lies face down or on their side, depending on the injection site (cervical, thoracic, or lumbar).

• Sterilization and numbing: The skin is cleaned, and a local anesthetic is injected to numb the area.

• Needle guidance: A thin needle is inserted into the epidural space under fluoroscopic guidance.

• Contrast dye: A contrast dye may be used to confirm correct placement of the needle.

• Injection: The steroid and anesthetic mixture is slowly injected into the epidural space.

• Monitoring: Patients are monitored briefly afterward to check for adverse reactions before being discharged.

The entire process is typically well-tolerated, and many patients can resume normal activities the next day. Some may feel a temporary increase in pain or pressure immediately following the injection, which usually subsides within 24–48 hours.

When to Consider an Epidural Steroid Injection

Not all cases of back pain require an injection. Epidural steroid injections are typically considered when conservative treatments—such as rest, physical therapy, and oral medications—have failed to provide sufficient relief. They are especially beneficial for patients with radiating pain caused by nerve inflammation or compression.

Candidates for ESI usually present with the following:

• Persistent lower back or neck pain with radiation into limbs

• Pain associated with a confirmed herniated disc or spinal stenosis

• Symptoms that interfere with walking, working, or sleeping

• Incomplete response to physical therapy or medications

In most cases, a physician will order imaging studies like an MRI or CT scan to confirm the diagnosis and determine the exact level of inflammation or compression. Based on these findings, the physician may suggest a series of injections spaced out over several months.

Benefits and Limitations of Epidural Steroid Injections

Epidural steroid injections can offer significant relief, but they are not a cure for spinal problems. Their effectiveness varies depending on the underlying condition, the severity of inflammation, and the individual’s overall health. Some people experience long-term pain reduction, while others may find only short-term relief.

Potential Benefits:

• Reduced inflammation around nerve roots

• Significant pain relief within days

• Improved ability to perform physical therapy

• Delayed or avoided need for surgery

• Low-risk, outpatient procedure

Despite these advantages, there are limitations. ESIs do not reverse structural damage like disc herniation or spinal stenosis. Also, the pain relief they provide is temporary—lasting from a few days to a few months. Repeated injections are typically limited to three per year due to potential side effects of corticosteroids, including hormonal imbalances, bone thinning, or blood sugar changes in diabetic patients.

Potential Risks and Side Effects

While generally safe, epidural steroid injections do carry some risks. The most common side effects are mild and temporary, such as soreness at the injection site or increased pain within the first 48 hours. More serious but rare complications may include infection, bleeding, nerve damage, or an adverse reaction to the medication or contrast dye.

Patients with certain health conditions—such as bleeding disorders, uncontrolled diabetes, or active infections—may not be ideal candidates. It’s important to discuss your full medical history with your healthcare provider before undergoing the procedure.

In very rare cases, complications like dural puncture (which can cause a spinal headache) or nerve root injury may occur. However, the use of imaging guidance significantly reduces these risks by improving precision.

What to Expect After the Injection

After receiving an epidural steroid injection, most patients can go home the same day. It is advised to rest for the remainder of the day, but full activity can typically resume within 24 hours. Pain relief may begin as soon as the anesthetic takes effect, though it often takes a few days for the steroid to reach peak efficacy.

Some patients may notice complete relief, while others experience partial improvement. It’s important to monitor symptoms and follow up with your physician to evaluate the outcome. A follow-up plan may include additional injections, physical therapy, or imaging to assess further treatment needs.

For those who respond well, ESIs can offer a valuable window of relief that allows the body to heal through physical therapy and lifestyle changes.

Role in a Comprehensive Treatment Plan

Epidural steroid injections should be viewed as one part of a larger treatment plan. They are not intended as a stand-alone solution but can serve as an important adjunct to therapy. Combining ESIs with stretching, strengthening exercises, ergonomic modifications, and weight management can yield better long-term results than any single treatment alone.

Patients are encouraged to adopt healthy habits and stay active as tolerated. Prolonged bed rest or inactivity can worsen spinal issues and delay recovery. A multidisciplinary approach, including pain specialists, physical therapists, and orthopedic professionals, often yields the best outcomes for chronic spinal pain.

Supporting Your Journey Toward Relief

Epidural steroid injections offer a scientifically supported, minimally invasive method of relieving nerve-related back pain. For individuals struggling with radiating pain from spinal conditions, these injections can provide crucial relief that opens the door to recovery. Delaware Valley Pain & Spine Institute, with locations in Chafont, PA, Marlton, NJ, and Trevose, PA, emphasizes the importance of patient education in managing chronic pain. Understanding the role and limitations of ESIs allows individuals to make informed decisions about their care and improve their quality of life.

Resources

Manchikanti, L., Singh, V., Falco, F. J. E., Benyamin, R. M., & Hirsch, J. A. (2013). Epidural injections for spinal pain: A review. Pain Physician.
Benzon, H. T., Huntoon, M. A., & Rathmell, J. P. (2015). Improving the safety of epidural steroid injections. Journal of the American Medical Association.
Carette, S., & Fehlings, M. G. (2005). Clinical efficacy and side effects of epidural steroid injections. Spine Journal.