Radiculopathy occurs when something irritates a spinal nerve—say a “slipped disc” causing a pinched nerve. This is also called sciatica . There are resident stem and other cells in the local tissues everywhere in our body. Many live around blood vessels. These are obviously also present in the disc and nerves in the epidural space and they usually play an important role in suppressing inflammation and repairing damage. We know, based on a copious in vitro (lab) data, that the high-dose steroids used in epidural injections can kill these cells. So the progression of the series of epidural steroid injections looks a little something like this:
How often cortisone injections are given varies based on the reason for the injection. This is determined on a case-by-case basis by the health care practitioner. If a single cortisone injection is curative, then further injections are unnecessary. Sometimes, a series of injections might be necessary; for example, cortisone injections for a trigger finger may be given every three weeks, to a maximum of three times in one affected finger. In other instances, such as knee osteoarthritis, a second cortisone injection may be given approximately three months after the first injection, but the injections are not generally continued on a regular basis.
What is cortisone?
It is a hormone produced by a small gland on top of the kidney called the adrenal gland. It is essential to the proper functioning of your body, particularly when under stress. Its absence is known as Addison's Disease, which without treatment is fatal. Cortisone is a normal body product therefore; there are no allergic reactions. In cases of people with severe allergies, it is one of our most effective treatment tools. Cortisone by itself is rarely used today as it is relatively short acting and of low potency. Semi-artificial cortisone derivatives, such as DepoMedrol, Celestone, Kenalog, and a number of others, are used with increased benefits and fewer side effects.