Lumbar epidural steroid injection

Overview

A lumbar epidural steroid injection (lumbar ESI) is a medical procedure in which anti-inflammatory medication, typically a steroid or corticosteroid, is injected into the epidural space surrounding the spinal nerves in the lower back. The primary objective of lumbar epidural steroid injections is to effectively manage chronic pain stemming from the irritation and inflammation of spinal nerve roots in the lumbar region of the spine. This chronic pain condition is known as lumbar radiculopathy, characterized by pain that may travel from the lower back to the hips, legs, and/or feet due to specific medical conditions or injuries.

Reasons for undergoing the procedure

Healthcare providers use lumbar epidural steroid injections to treat lumbar radicular pain, often referred to as sciatica. This condition causes symptoms like pain, numbness, muscle weakness, and tingling that radiate from the lower back down the leg.

Conditions causing lumbar radicular pain include:

• Lumbar herniated disk: Occurs when the inner disk material presses on spinal nerves due to a damaged disk.
• Lumbar degenerative disk disease: Happens when the cushioning between vertebrae wears down, leading to nerve root inflammation.
• Lumbar spinal stenosis: Involves the narrowing of spinal spaces, which can irritate nerves and cause lower back pain, especially during activity.
• Lumbar osteoarthritis (spondylosis): Results from aging-related changes in the lower back bones, disks, and joints, leading to nerve irritation.

Lumbar epidural steroid injections can also be used to treat:

• Localized low back pain: Varies in intensity and can be sharp or dull.
• Neurogenic claudication: Causes pain or tingling in the lower back, legs, hips, and buttocks, especially during standing or walking.

Risk

Lumbar epidural steroid injections (ESIs) are generally considered safe, but like any medical procedure, there are potential risks and complications, although they are relatively rare. Here are some of the risks and complications associated with lumbar ESI injections:

• Low blood pressure: Occasionally, lumbar ESIs can lead to a drop in blood pressure, which may result in feelings of lightheadedness.
• Severe headache: In some cases, there may be a severe headache caused by a leakage of spinal fluid.
• Infection: There is a small risk of infection resulting from the epidural procedure, such as epidural abscess, discitis, osteomyelitis, or meningitis.
• Medication reactions: Some individuals may experience adverse reactions to the medications used in the injection, such as hot flashes or skin rashes.
• Bleeding: Accidental damage to a blood vessel during the injection can lead to bleeding, potentially causing a hematoma or blood clot formation.
• Nerve damage: There is a rare risk of damage to the nerves at the injection site.
• Bladder and bowel Issues: Temporary loss of control over bladder and bowel function can occur, possibly necessitating the use of a catheter for urination.
• Bone and muscle weakening: Frequent or high-dose ESI injections may weaken the bones in the spine or nearby muscles. As a precaution, most healthcare providers limit patients to two to three ESIs per year.

While extremely uncommon, there are also long-term complications that can arise from lumbar ESI injections, including:

• Permanent neurologic deficit: In rare instances, permanent spinal cord or nerve root damage may occur as a result of the injection, leading to chronic pain or neurological deficits.
• Permanent paralysis: Although highly unusual, there is a risk of permanent paralysis if a hematoma develops, causing a buildup of blood between the dura mater and the spinal cord.

Procedure

Lumbar epidural steroid injections involve the precise injection of steroids into the epidural space around the spinal cord, administered by healthcare providers. This space encases the spinal cord with connective tissue, blood vessels, fat, and spinal nerves. The steroids help reduce pressure and inflammation on the nerves, particularly those causing discomfort. However, their effectiveness varies among patients, often providing short-term pain relief lasting up to three months or longer. Highly skilled medical professionals like radiologists, anesthesiologists, neurologists, surgeons, and physiatrists specializing in physical medicine and rehabilitation perform lumbar ESIs due to the procedure’s need for precision.

Before the procedure

Prior to receiving a lumbar epidural steroid injection (ESI), patients must communicate specific information to their healthcare provider, as this information is essential in anticipation of the use of fluoroscopy imaging, which is a form of X-ray imaging:

• Pregnancy and medication disclosure: Informing the healthcare provider about a patient’s pregnancy or suspicion of pregnancy is crucial, as is providing a comprehensive list of all current medications, which should encompass prescription drugs, over-the-counter remedies, herbal supplements, and dietary additions.
• Detailed preparatory instructions: The healthcare provider will provide the patient with precise instructions for preparing for the lumbar ESI injection, and it is crucial for the patient to diligently follow these guidelines.
• Specific preparatory measures: The healthcare provider may prescribe specific preparatory measures, which may include fasting for several hours before the lumbar Epidural Steroid Injection (ESI), adjustment of medication dosages, especially blood thinners, the possibility of undergoing a magnetic resonance imaging (MRI) or computed tomography (CT) scan before the lumbar ESI to pinpoint the exact location requiring treatment, and ensuring that the patient has a companion available to drive them home in case they are taking a sedative for the procedure.

By following these steps and communicating effectively with their healthcare provider, the patient can ensure a well-prepared and safe experience during their lumbar epidural steroid injection.

During the procedure

A lumbar epidural steroid injection (ESI) is typically performed in a hospital or outpatient clinic and usually takes between 15 to 30 minutes. During the procedure, it’s crucial to remain very still.

There are various methods for accessing the epidural space around your spinal cord in your lower back, including:

• Interlaminar ESI (IESI): In this method, the needle is inserted between two laminae, which are flat bone plates on each vertebra in your spine. These laminae form the outer wall of the spinal canal and protect the spinal cord. Interlaminar lumbar ESIs are commonly used for temporary pain relief in conditions like disk herniation, spinal stenosis with or without radicular pain, and localized low back pain.
• Transforaminal ESI (TFESI): With this approach, the needle path is through the foramina, which are openings where nerve roots exit the spine. Transforaminal lumbar ESIs are typically used to provide temporary pain relief for radicular pain caused by conditions like disk herniation or specific nerve root injuries.
• Caudal ESI: In this technique, the needle is guided through the sacral hiatus, located near the base of your sacrum, just above your tailbone, to reach the lowest spinal nerves. The sacrum is the triangular bone in your lower back between your hip bones. Caudal lumbar ESIs are often used to provide temporary pain relief for “failed back” syndrome and generally carry fewer risks compared to interlaminar and transforaminal ESIs.

The general steps of a lumbar epidural steroid injection procedure are as follows:

• You will change into a medical gown and lie face down on a comfortable table with a pillow under your abdomen. Your healthcare provider may administer a sedative to help you relax.
• Your provider will thoroughly cleanse the low back area where they will insert the epidural needle to minimize the risk of infection.
• Fluoroscopy, a type of imaging guidance using X-ray or radiology, will be used to precisely guide the epidural needle to the correct position.
• Local anesthesia may be injected with a small needle near the insertion site to reduce pain when the larger epidural needle is inserted.
• Once the epidural needle is correctly positioned in the epidural space surrounding your spinal cord, a contrast material will be injected. This ensures the needle is in the epidural space and not within a blood vessel or other tissues, ensuring the medication reaches the targeted inflamed nerves.
• The provider will then slowly inject the medication, typically an anti-inflammatory medication like a steroid or corticosteroid. Some providers may use a mixture of corticosteroid, normal saline, and a local anesthetic.
• After the injection is completed, pressure will be applied to the site to prevent bleeding. The area will be cleaned again, and a dressing will be applied. You’ll then be moved to a chair or bed to rest for a few minutes to an hour, allowing your provider to monitor for any adverse reactions before you are discharged.

After the procedure

After your lumbar ESI, it’s possible for your pain to temporarily worsen for about two to three days before showing signs of improvement. Epidural steroid injections typically start to take effect within a range of two to seven days, offering pain relief that can endure for several days, a few months, or even an extended duration.

Outcome

Lumbar epidural steroid injections (ESIs) can provide temporary pain relief for back issues, typically up to 6 months. They are most effective for radicular pain caused by conditions like lumbar herniated disks or spinal stenosis. Studies show that for those with radicular pain due to disk herniation, about 70% experience at least 50% improvement within one to two months, and 40% still feel better after 12 months.

The main purpose of lumbar ESIs is to alleviate pain temporarily, allowing for physical therapy or avoiding more invasive treatments. People may be limited to two to three injections per year. If you experience severe headaches when upright (improving when lying down), fever (indicating infection), loss of bladder or bowel control, or leg numbness/weakness (suggesting nerve injury) after an ESI, contact your healthcare provider or seek immediate medical attention.