Joint aspiration
Drawing off fluid from a swollen joint, which can both relieve symptoms and help reach a diagnosis, performed accurately under ultrasound
Joint aspiration is a procedure in which fluid is drawn off from a swollen joint using a fine needle. It serves two purposes: it can relieve the discomfort of a tense, swollen joint, and the fluid can be examined to help reach a diagnosis, for example to look for crystals or signs of infection. Performing it under ultrasound guidance helps place the needle accurately.
Written for patients and reviewed by Dr Liubov Borukhson, Consultant Rheumatologist (GMC 7021928). Last clinically reviewed: June 2026.
Why it is done
Joint aspiration can be helpful in a few situations:
- To relieve the pressure and discomfort of a tense, swollen joint
- To examine the fluid and help diagnose the cause, such as a crystal arthritis
- To help guide the right treatment based on what the fluid shows
How ultrasound helps
Using ultrasound during the procedure means the joint and the needle can be seen in real time, so the fluid can be reached accurately, even where a joint is difficult to enter or the fluid is hard to feel. This makes the procedure more precise and, where an injection is also appropriate, allows it to be given accurately at the same time. You can read more on the ultrasound clinic page.
What to expect
The skin over the joint is cleaned, and ultrasound is used to guide the needle. The procedure usually takes only a short time. Most people find it well tolerated, with a feeling of pressure rather than sharp pain, and any specific aftercare is explained to you at the time.
Part of a one-stop approach
Because Dr Borukhson uses point-of-care ultrasound during the consultation, assessment and, where appropriate, aspiration can often take place within the same visit. This can speed up both relief and diagnosis. Whether aspiration is the right step is always discussed with you first.
A swollen joint that needs assessment?
A specialist assessment with ultrasound can establish the cause and, where appropriate, draw off fluid for relief and diagnosis in the same visit
Book an appointment