Corticosteroid injections may be recommended for a variety of painful conditions, including sports injuries, joint pain and osteoarthritis pain.
Corticosteroids are related to the natural steroid made by the body called cortisol.
Corticosteroid injections may be recommended by a doctor to both reduce inflammation and help prevent long-term muscle and ligament damage.
A fine needle is used to inject the corticosteroid into the affected joint. This procedure is called an intra-articular injection. It may be painful, so anaesthetic may also be given.
Outcomes vary between individuals and the condition being treated.
For most people, pain is relieved significantly or disappears completely within four weeks of starting the treatment.
For others, the pain relief is temporary and the pain returns some weeks later. Follow-up injections may be given.
There may be some discomfort for 48 hours after the injection where the needle went in. Other than that, the risk of any side effects is small.
Getting a corticosteroid injection: What to expect
Most injections into the knee or a smaller joint, like that at the base of the thumb, are simple procedures that can be done in a doctor’s surgery. When performed by an experienced physician, the injection is only mildly uncomfortable.
First, the doctor cleans the skin in the area with an antiseptic. If the joint is puffy and filled with fluid, the doctor may insert a needle into the joint to withdraw the excess fluid and examine it. Removing the fluid rapidly relieves pain also because it reduces pressure in the joint and may speed-up healing. Next, the doctor uses a different needle to inject the corticosteroid into the joint.
Injecting a large joint, like the hip, is more complicated and may require imaging tests to help the doctor guide the needle into the joint. Experienced rheumatologists, orthopaedic surgeons, anaesthetists and radiologists may inject the facet joints of the lower spine.
What are the risks of corticosteroid injections?
Despite their benefits, corticosteroids are associated with a range of potentially dangerous side effects, including increased risk of infection, weight gain, gastrointestinal ulcers and bleeding, osteoporosis, elevated blood pressure and blood glucose levels, and eye problems, including cataracts and glaucoma.
However, injecting corticosteroids directly into a joint minimises or eliminates the risk of most of these side effects. However, there are some special, though uncommon, risks of joint injection. They include:
- Injury to the joint tissues, particularly with repeated injections
- Thinning of joint cartilage
- Weakening of the ligaments of the joint
- Increased inflammation in the joint caused by a corticosteroid that has crystallised
- Irritation of the nerves, caused by the needle during an injection or by the medication
- Introduction of infection into the joint
- Whitening of the skin or local thinning of the skin at the injection site
It’s not known if frequent corticosteroid injections lead to joint damage. If you have an infection in or around a joint or you’re allergic to one or more of the medications that are injected, you should not have a joint injection.
Conditions treated with corticosteroid injections
Corticosteroid injections may be recommended for osteoarthritis symptoms if other types of pain relief have not been effective.
Corticosteroid injections may also be a treatment option to help reduce inflammation for bursitis. In this condition fluid-filled sacs between tendons and bones become swollen.
Corticosteroid injections can relieve pain from tendonitis, when the tendons attaching muscle to bone become inflamed and painful.
Systemic corticosteroid injections may be injected into the bloodstream for conditions requiring urgent treatment and affecting the whole body rather than specific joints.