Dr Duncan co-authored a comprehensive corticosteroid injection consumer guide for Inside Radiology, a project of The Royal Australian and New Zealand College of Radiologists, with additional information for health professionals.
Inside Radiology guides: Bursal Injections · Carpal Tunnel Injections
Why have I been referred for an ultrasound-guided steroid injection?
The most common cause of joint pain is arthritis. Though there are many causes of arthritis, most are associated with some form of joint inflammation or synovitis. A common cause of soft tissue pain is bursitis or tendinopathy. A bursa is a soft-tissue space between two structures such as bone, muscle and tendon — essentially a "soft tissue joint".
A bursal or joint injection is generally undertaken to reduce inflammation in joints (synovitis), bursa (bursitis), or around tendons (tendinopathy). By injecting small doses of corticosteroid and/or local anaesthetic directly into these structures, pain arising from the site should be relieved. The reduction in pain and swelling helps the function of the soft tissues on either side of the joint or bursa, which in turn can make physiotherapy more effective.
To ensure the injection goes into the joint or bursa itself, where it has the best chance of working, the needle is usually guided by imaging — most often using ultrasound.
Are there other reasons I might have been referred?
Sometimes it can be difficult for your doctor to know exactly what is causing your pain. If the pain is not due to bursitis or from the adjacent tissues, the injection may not improve your symptoms. While that can be disappointing, it can be helpful information for your doctor — it means other possible causes need to be investigated.
How do I prepare for a steroid injection?
- No specific preparation is needed.
- If the injection is in the foot, hand, or arms you may need a driver afterwards.
- Please bring any previous X-rays, ultrasound, CT, or MRI scans related to this problem.
- Wear comfortable clothing with easy access to the area being injected.
What happens during the procedure?
You'll be placed in a comfortable position, usually on a scanning bed. A staff member and/or the doctor will explain the procedure and you'll have an opportunity to ask any questions.
The area to be injected is scanned and the skin is cleaned. Sometimes a mark is placed on the skin to help guide the needle entry. A narrow-bore needle is then passed from the skin directly into the joint or bursa while being scanned (usually with ultrasound) to help guide the doctor to place the injection accurately.
Most patients experience only mild discomfort. Some areas — particularly small joints in the hand, foot, or around the heel — can be more uncomfortable than others.
After the injection
- You may have a temporary increase in symptoms for the first 24–48 hours; this can be managed with ice, rest, and paracetamol.
- Rest the treated area for the remainder of the day where possible.
- The corticosteroid effect typically begins within a few days and may continue to improve over 2–3 weeks.
- If the area becomes red, hot, or significantly more painful, contact your doctor — infection is rare but possible.
Are there risks?
Corticosteroid injections are generally well tolerated. The main risks include:
- Post-injection flare — brief worsening of pain in the first 24–48 hours
- Skin changes — occasional thinning or lightening of skin at the injection site
- Infection — very rare with ultrasound-guided injection
- Effects on cartilage — repeated injections may have effects on cartilage, which is why frequency is usually limited