Patients do not get all the same side effects from a steroid injection as they do from having high dose . steroids or prolonged courses of steroid tablets - this is because the steroid acts just locally, within the joint, to reduce inflammation. As well as steroid we are able to inject Hyaluronic Acid ( Ostenil, Synvisc or Duralane) into the joint. This acts as a synthetic synovial fluid(which helps lubricate the joint) reducing pain and improving movement. This treatment is especially beneficially in the case of arthritic(wear and tear) changes.
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.
Addiction to cortisone was the subject of the 1956 motion picture, Bigger Than Life , produced by and starring James Mason . Though it was a box-office flop upon its initial release,  many modern critics hail it as a masterpiece and brilliant indictment of contemporary attitudes towards mental illness and addiction.  In 1963, Jean-Luc Godard named it one of the ten best American sound films ever made.  John F. Kennedy needed to regularly use corticosteroids such as cortisone as a treatment for Addison's disease .