What is the epidural space and what is an epidural injection?
The covering over the nerve roots in the spine is called the dura. The sleeve-like space surrounding this dura is called the epidural space. Nerves travel through the epidural space before they travel into your arms, chest or legs. The nerves leave the spine from small nerve holes. The nerves may become inflamed due to irritation from a damaged disc or from contact with a bone spur. Inflammation of these nerves in the thoracic spine may cause pain in your mid-back, along your ribs, to your chest wall or abdomen. Inflammation of these nerves in the lumbar spine may cause pain in your low back, hip, buttock and legs.
An epidural injection places anti-inflammatory medicine (steroid) into the epidural space to reduce nerve inflammation, and hopefully reduce your symptoms. By stopping or limiting nerve inflammation, we may promote healing and speed up "mother nature," thereby reducing your pain. Although no always helpful, epidural injections reduce pain and improve symptoms in most people within 3-7 days. They may provide permanent relief or provide a period of pain relief that will allow other treatments like physical therapy to be more effective.
You may have up to three epidural injections spaced approximately 2-4 weeks apart. Performing a repeat injection depends on your response to the prior injection. If you obtain excellent relief from an epidural, you do not need to have it repeated. If an epidural injection provides minimal benefit (less than 30%), your physician may choose another type of injection to improve your changes of obtaining relief or to provide diagnostic information. If you have partial benefit (greater than 30% relief), the epidural can be repeated for possible additive benefit.