ESI

How does an Epidural Steroid Injection work?

Epidural Steroid Injection (ESIs) are commonly used to help control back and neck pain by reducing inflammation and swelling around the spine and nerves.

Steroid injections are performed to diminish symptoms of radicular pain (pain radiating down an arm or leg) or Spinal Stenosis.

Steroid injections are for temporary relief of pain; they are not a cure. Pain relief often lasts from a couple of weeks to months. There are rare but serious risks involved.

Procedure

During the ESI procedure you will be lying on your abdomen with a pillow under the pelvis or a ramp with a head support. A pillow will be placed under your lower legs for comfort.

The translaminar ESI is performed using fluoroscopy to guide the placement of a small needle between two vertebra into the epidural space. Placement is confirmed with a small amount of iodinated contrast or dye. Then the steroids are injected into the area. Anesthetics are placed in the lumbar region with the steroids, giving short term pain relief (usually 1-6 hours). The steroids generally work in 24-72 hours and last 2 weeks to several months, depending on the person.

A caudal injection is performed in the same fashion as a conventional ESI but is very low in the vertebral column. A small needle is placed in opening at the tip of the sacrum, which has a direct connection to the epidural space. Steroids and analgesics placed in this area move upward to bathe the nerves in the lower back.

Complications are rare but can include but are not limited to: headache, damage to nerve roots or spinal cord, bleeding, infection, allergic reaction or steroid induced reactions.

Location of ESIs

There are two openings in the spine where a needle can be inserted for the ESI. These consist of: Translaminar and Caudal. The ESIs can be performed in the cervical, thoracic and lumbar areas.

How to prepare

People taking blood thinners should contact the facility to verify how long to be off the blood thinning medication. Depending on the blood thinner, blood may need to be drawn at a laboratory to verify that the blood is not too thin to perform the procedure.

After the procedure

You will be placed on a cart and allowed to relax for 10-30 minutes. You may have some numbness in your legs if the caudal or lumbar region was injected. This is normal and is related to the anesthetic. The feeling should return to normal after the anesthetic wears off (usually 1-6 hours).

You will be asked to decrease your activity for 24 hours (no strenuous activity or heavy lifting). On the day of your injection you should not drive or operate any machinery. This allows the steroid to remain in the location where the doctor placed it to decrease the inflammation that is causing your discomfort.

A Medical Doctor with special training in Interventional Radiology will perform the procedure using sterile technique, with x-ray guidance.

Activities following the procedure

How long does the procedure take?

Typically the procedure takes 5-10 minutes and recovery of 10-30 minutes.

How long will the steroid work?

Each individual is different but most people have relief of their symptoms for 2 weeks to several months.

Why is this procedure performed?

ESIs are performed by injecting steroids into the epidural space, the space surrounding the spinal cord.Steroids are an anti-inflammatory medication that when injected into the epidural works on the nerves, nerve roots, disc spaces, and connective tissue to decrease the inflammation. When inflammation is reduced it allows the nerves to work better and decreases pain, numbness and tingling.

Facet Joint injection (Facet Block)

A facet joint injection is an injection of steroid medication into a facet joint (spinal joint) to reduce pain caused by inflammation or osteoarthritis, degenerative arthritis of the facet joint. An injection may also be made around the small nerves that connect with the facet joint to help determine if the joint is the source of pain.

Selective Nerve Root Block

A selective nerve root block is an injection at the level of the symptomatis nerve (outside the epidural space) as it exits the spinal column. Selective nerve root blocks are used both for diagnostic purposes (to determine if a specific nerve root is the source of the problem) and to relieve radicular pain caused by irritation of a specific nerve root.If a specific nerve is actually the cause of pain the local anesthetic in the injection will give immediate relief. The steroids in the injection will reduce inflammation over the next few days and possibly provide relief of pain that lasts for weeks to months. Herniated disk in the lumbar spine causing low back pain with leg pain (sciatica) is a common condition treated by a selective nerve root block.

There are rare but serious risks involved in a selective nerve root block, as in any spinal injection, as well as the possibility of side effects from corticosteroids.

SI Joint Injections

The SI joint is located between the sacrum and pelvic bones. Sometimes injecting the SI joint with local anesthetic may help your doctor determine whether the SI joint is the source of your pain. If the joint is injected and your pain does not go away, it is probably coming from somewhere else. If the pain goes away, your doctor may reinject with cortisone and local anesthetics into the SI joint. Cortisone is used to treat inflammation from SI joint arthritis. The injection usually gives temporary relief for several weeks or months.

Specific Indications

SI joint injections can be used both to treat pain and to determine the source of the pain. This injection usually requires the use of fluoroscopic guidance or a CT scan in order to make sure the needle is placed correctly in the joint.

Risks of Epidural Steroid Injections

There are rare but serious risks involved in all spinal injections.
Side effects from corticosteroids may also occur though long-term systemic side effects are unlikely as only a small amount of corticosteroids enters the bloodstream.Risks / Complications / Side Effects of Spinal Injections

Some possible risks of a spinal injection are dural puncture, infection, bleeding, allergic reaction, arachnoiditis, worsening of pain, nerve damage or spinal cord damage, paralysis, or death. Catastrophic complications are extremely rare, e.g. paralysis or death.

Some of the complications of spinal injections:

Dural Puncture: Perhaps the most common, but usually not too serious, complication that may occur in as many as one to two percent of epidural spinal injections is the accidental dural puncture (puncture of the sac containing spinal fluid around the spinal cord) resulting in a leakage of spinal fluid into the epidural space.The resulting reduction of cerebrospinal fluid pressure may cause a spinal headache. Spinal Headaches tend to worsen upon standing and improve when lying down. The headache usually resolves within a few days but can last longer. Most cases eventually resolve by pushing fluids with salt and caffeine without treatment. Rarely, a persistent spinal fluid leak develops which may be treated with a blood patch. A small amount of a person’s own blood can be injected into the epidural space, where it will clot and usually seal the leak.

Infection: Minor infections occur in less than two percent of injections. Serious Infections / Epidural Abscesses are rare. Diabetics are at a higher risk of infection.

Bleeding / Epidural Hematoma: An epidural hematoma is a large pocket of blood that accumulates in the epidural space when bleeding continues after injury of epidural vein. This can compress the spinal cord and cause permanent damage if not treated quickly. Patients taking blood-thinners need to be evaluated prior to injections. In most cases thinners are held to normalize blood clotting for the procedure. This is a rare complication.

Allergic reaction: to the medication in the injection is rare and is usually a reaction to the preservative or x-ray contrast dye in the injection and not the steroid.

Nerve damage or spinal cord damage: Very rarely, the needle itself can cause injury to nerves; compression of nerves or the spinal cord from hematoma (pocket of blood) or pus (from infection) may result in damage. Obstruction of blood supply may also cause permanent nerve or spinal cord injury.

Arachnoiditis: A painful condition caused by the inflammation of the arachnoid membrane (the middle membrane of the three membranes covering the spinal cord) that may occur if medication is injected into the spinal fluid. Extremely rare.

Corticosteroids: Corticosteroids (or steroids) are similar to cortisol, which is produced naturally by your own body, but these synthetically produced steroids are more potent and longer lasting. Corticosteroids have powerful anti-inflammatory effects.

Local Side Effects of Corticosteroids in Spinal Injections: Too many steroid injections into the same area may weaken tendons and ligaments and cause thinning of joint cartilage.

Short-term side-effects from the steroids in a spinal injection: There may be bouts of facial flushing with a feeling of warmth the day after the injection. For several days after a spinal injection diabetics need to monitor their blood sugar carefully as blood sugar levels may be elevated.

Systemic

High dosages of oral corticosteroids taken daily for prolonged periods of time can have serious systemic side effects including bone loss ( osteoporosis), increased risk of infections and diabetes and cataracts, thinning of skin, stretch marks, increased facial/body hair growth, acne, fluid retention, weight gain with redistribution of fat (fat deposits on back and face, thinning of limbs), muscle weakness, decreased resistance to infections, stomach ulcers, mood swings, insomnia, suppression of the body’s own production of cortisol, etc.Many of the side effects go away within a few months after discontinuing the steroids. Some side effects, such as stretch marks, osteoporosis and cataracts (cataracts are fortunately a rare side effect) do not go away on their own.

Spinal Injections in Summary

Steroid injection risks are rare but can be serious. These include but are not limited to, loss of bone density, decreased immunity and change in adrenal function. If you are on blood thinners you may have to hold them to prevent bleeding complications if you are sick or on antibiotics you need to complete your course of therapy prior to your procedure. Due to potential systemic side effects, typically only 3-4 steroid injections are recommended per year total, regardless of location of injection.