Epidural Steroid Injection (ESI)

Epidural injections contain a strong anti-inflammatory agent called corticosteroid and an anesthetic for pain relief. It is not the same as an epidural anesthesia given before birth to decrease labor pain. Epidural injections are given to relieve pain in the neck, back, arm and leg due to inflammation of spinal nerves from conditions such asspinal stenosis, spondylolysis, herniated disc, degenerative disc and sciatica.

Epidural injections are administered into the epidural space of the spine.  The epidural space is the space between the outermost covering of the spinal cord (dura mater) and the wall of the spinal canal. It is approximately 5mm wide and is filled with spinal nerve roots, fat and small blood vessels.

Indications

Epidural injections are recommended based on pain patterns and used to treat pain primarily from the spine.

Procedure

You will be taken to the pre op area where trained nursing staff will get you ready for the procedure, by taking vitals and reviewing your medications. Your blood sugar and coagulation status may also be checked if needed. Then you will enter the procedure room where you will lay, usually, face down or on a table.

The injection site is then cleaned and injection of a local numbing agent is given in the area so that you don’t feel pain during the procedure.

A thin hollow needle is then inserted into the epidural space. The doctor is guided by fluoroscopic X-ray to place the needle in the correct position. This system gives real time X-ray images of the position of the needle in the spine on a monitor for the surgeon to view..

A contrast material is then injected through the properly placed hollow needle to confirm that the drug flows to the affected nerve when injected.

When the doctor is satisfied with the position of the needle, the anaesthetic drug and corticosteroid are injected through the same needle inserted in the spine.

You may feel some pressure during the injection but mostly the procedure is not painful. The needle is removed and the injection site is covered with a dry, sterile bandage. The procedure takes about 3-5 minutes to complete.

Risks and Complications

With the use of live imaging though X-ray machines, contrast dye, and physicians trained in the latest interventional techniques, complications are rare. But with all

medical procedures, complications may occur.  To help minimize risk please follow all directions given to you by your care provider.  Have all your treatment options explained, so you are aware of the risks and benefits of these procedures. 

Some complications may include:

  • Spinal Headache: If spinal fluid leaks out of the intrathecal space, you may have a headache that gets better when you lay down. This headache usually gets better by lying flat in bed for 12 to 24 hours and drinking caffeine.  However on occasion, headaches may last longer and need further evaluation.
  • Infection: Your pain physicians clean and sterilize your back before every procedure to prevent this from occurring. On rare occasions oral antibiotics may be needed.
  • Allergic Reaction: This may occur if you have allergies to any medication used. Typically this is pretreated and on occasion your physician may recommend medications for you to take after the procedure. Pay close attention to any rashes and difficulty breathing because that may indicate need for emergent attention.
  • Worsening pain:This may occur after the procedure due to the needle puncture and can last from 3 days to a week. Usually this pain resolves and does not cause any lasting impact.

There are many side effects of corticosteroids. However, by limiting the cumulative dose of medication used, these risks are reduced. However, some symptoms you may feel include:

  • Insomnia
  • Heart Palpitations
  • mood changes

Epidural injections may take 2-7 days to show any effect.  They may need to be repeated. And as always, follow the instructions of your care provider and have your questions answered prior to the procedure.