Cortisone is a substance similar to a natural steroid hormone produced by the body. Cortisone injections are given into a painful joint, soft tissue or bursae (fluid-filled sacs that cushion spaces around and between your joints, tendons and bones) to reduce pain and swelling.
They're used in conditions such as bursitis, frozen shoulder, gout, rheumatoid arthritis, osteoarthritis, tendinitis, carpal tunnel syndrome, rotator cuff damage, tennis elbow and trigger finger.
Cortisone injections are used when there is a flare-up or the pain isn't responsive to other treatments, or when other medicines can't be used.
They provide short-term pain relief, usually for up to a month, but don't cure the problem or improve joint function or stiffness.
Video: Cortisone injection
(RheumInfo, Canada, 2011)
Note: this video is from Canada so may have information that differs from New Zealand recommendations.
Avoid regular repeated injections
Cortisone injections are used as short-term relief. Regular repeated steroid injections aren't recommended. Frequent injections into the same area can cause the bone, ligaments and tendons to weaken over time.
Generally, cortisone injections aren't given more often than 3 or 4 times a year and they are given at least 6 weeks apart.