A painful swollen joint or a tender area around a tendon is usually caused by inflammation. In a joint this may be due to arthritis and in a tendon is called tenosynovitis.
Inflammation is usually treated by rest and if appropriate, by non-steroidal medication, such as ibuprofen. Physiotherapy may be appropriate for some conditions.
If the pain and inflammation continues, a cortisone injection may be recommended.
Joint injections are done for people with rheumatoid arthritis, osteoarthritis and many other conditions. Sometimes cortisone is injected into the tissues around joints, into an inflamed bursa or around tendons because this can help with the inflammation and swelling.
What are the advantages of cortisone injections?A single injection can avoid certain side effects that can accompany many oral anti-inflammatory medications, notably irritation of the stomach. In about 70% of cases, the steroid reduces the swelling and pain a patient has.
How long will it be before my joints feel better?The local anaesthetic will start to reduce the pain within a few minutes of the injection. This pain relief will last for several hours, there may be numbness from the anaesthetic which will usually ease within 24 hours.
The steroid will take longer to start working; sometimes it can be 1-2 days after the injection, before the pain starts reducing. It is important to rest the joint for the first 48 hours.
In the first 48 hours the pain may get slightly worse before it starts getting better. During this period to take painkillers such as paracetamol, or use a cold pack. The joint that has been injected will hopefully feel better for up to 3 months and sometimes much longer, but everybody is different so it may not last this long.
What are the disadvantages and side effects of cortisone injections?Disadvantages of cortisone injections are the necessity of piercing the skin with a needle as well as potential side effects.
Facial flushing may occur but lasts only briefly: sweating and insomnia are also uncommon side effects. Rarely cortisone injections can interfere with the menstrual cycle or lead to an elevation in blood sugars in diabetics.
Complications are uncommon but include:
- Shrinkage (atrophy) around the site of the injection.
- Lightening of the colour (depigmentation) of the skin at the injection site – this depends on how superficial the structure injected is.
- Introduction of bacterial infection into the body (sterile precautions are taken to help prevent this). If your joint becomes more painful, red or hot and swollen you should see your doctor immediately.
- Local bleeding from broken blood vessels in the skin or muscle
- Soreness at the injection site, and aggravation of inflammation in the area injected because of reactions to the corticosteroid medication (post injection flare). A true allergic reaction to cortisone is very rare.
- Tendons can be weakened by corticosteroid injections in or near tendons. Tendon ruptures as a result are very uncommon.
It should be emphasised that though each of these side effects and complications is possible, they usually do not occur.
What are the advantages of an Ultrasound guided steroid injection?An ultrasound guided steroid injection is more accurate. The doctor can directly visualise the end of the needle and see exactly where the corticosteroid is being injected in real time. Studies have shown that this can give a better initial response to the injection. An ultrasound guided injection is also less painful for the patient than a normal injection.
What can I do after a corticosteroid injection?You are advised not to drive immediately after a corticosteroid injection but you can resume driving the following day. You will be advised to rest from aggregating activities for at least 48 hours but this may be up to 1 week. You will be encouraged to see a therapist for strengthening exercises and rehabilitation as this will help to prevent the pain recurring when the cortisone injection has worn off.
