What is it?
The synovial membrane is the smooth, lubricated lining inside the ankle which aids movement of the joint. When it gets inflamed as a result of injury, infection or wear and tear, it can swell up, restrict movement and cause pain.

How does it feel?
Pain with certain weight bearing or non-weight bearing movements of your ankle. Sometimes there is swelling in the ankle, and it will usually feel hot. The symptoms can be vague and only increase when doing activities such as running or walking.

Diagnosis
The surgeon will look at swelling and movement of the ankle. If you have pain, the surgeon might give you local anaesthetic injections, to work out where the pain is coming from. You may also have an MRI scan to ascertain that the synovium is swollen.

Surgery
During arthroscopic surgery, small incisions are made, and the inflammatory tissue is removed from the inside of the ankle joint. The piece of tissue (biopsy) will be sent away for analysis.

Recovery
You should be able to walk normally within two days after the procedure.