Steroid injections are typically composed of an anesthetic such as lidocaine and/or marcaine as well as the selected steroid. The lidocaine and marcaine take effect almost immediately and can provide relief for several hours. Typically if pain is relieved during this time, then we are addressing the appropriate pain generator. The steroid portion of the injection often takes 2-3 days to begin to take effect and lasts 3 months on average. There are no formal limits on the number of steroid injections one can receive into a joint. Most orthopedic surgeons suggest not receiving more than 4 injections per year.
Adverse Reactions: Overall injections are considered to be safe – with very few problems.
- Infection – This is an extremely rare, but sometimes severe complications. If you have redness and severe pain following an injection – please seek emergency care.
- Steroid flare – Sometimes patients experience an elevation in pain the day after a steroid injection. This often resolves over the course of 24 hours.
- Elevation in blood glucose – Patients who undergo a steroid injection with a history of diabetes are encouraged to monitor their blood sugar levels and expect an increase over the next three days.
How Steroid Injections work:
Cortisol is a hormone naturally produced by the body during stress (fight or flight response). This is done to suppress the inflammatory response during stress. Cortisone is a strong anti-inflammatory that works in a similar fashion, suppressing the inflammatory system, and thus naturally produced pain generators.
Concern regarding degenerative effects on cartilage:
There are conflicting data regarding whether cortisone injections cause worsening arthritis. There are some studies demonstrating worse arthritis in 6% of patients after a steroid injection. The studies on damage due to steroid injections is not well done and is unreliable. These studies are unable to prove that the arthritis is worsening because of the injections, or if the study recipients already had worsening arthritis in spite of these steroid injections. This is why most physicians provide a balanced view on providing steroid injections on a limited bases of no more than 3 – 4 per year per joint.