A ganglion is an outpouching of synovium; the layer of cells that lines the shock pad in our joints. Over repeated trauma, the synovium escapes the joint space and goes near the skin. This causes a firm lump, typically on the wrist.
One treatment for a ganglion is the injection of a steroid. A steroid is immunosuppressive and calms the inflammation. Studies show that it reduces the ganglion in 50% of people however long term, only 10% of ganglions will go away.
The procedure involves a large needle being inserted straight into the ganglion, the contents withdrawn and steroid injected.
The risks include pain, bleeding, infection and failure of the procedure.
REFERENCE
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6823827/
