An epidural is an injection that delivers steroids directly into the epidural space. The epidural space is the space inside the spine between a membrane and the vertebral wall and is filled with fat and small blood vessels. There are often inflammatory factors and other substances that generate pain and this inflammation can cause significant nerve root irritation and swelling.

Steroids (corticosteroids) have been shown to reduce inflammation by inhibiting the production of substances that cause inflammation, the epidural injection can be highly effective because it delivers the medication directly to the site of inflammation.
 
Patient Information
Proper placement of the injected medication is crucial, but it can be difficult. There are many different structures around a joint that can cause pain. Is there a torn tendon? An inflamed bursa? Or damaged cartilage from arthritis? Each of these problems require the medicine to be placed in a specific location.
 
The numbing agent included in most joint injections serves two purposes. In addition to making the injection itself less painful, the anesthetic can help verify proper placement of the needle. Your immediate relief of pain indicates the needle is in the right place.

A variety of substances have been used in trigger-point injections, including numbing agents, botulinum toxin (Botox), corticosteroids and other anti-inflammatory drugs. In some cases, pain relief occurs simply from the physical piercing of a trigger point with a needle — even when no medicine is injected.

Before the Procedure
No preparation is usually required for an ESI examination.
 
After the Procedure
The immediate effect after the injection is usually from the local anesthetic injected. This wears off in a few hours. The cortisone starts working in about 3 to 5 days and its effects can last for several days to a few months. Please arrange for transportation home