Bummer to hear about your ankle.
How is the healing/recovery progressing?
The synovium is a lining of the protective sheath that covers tendons. Tenosynovitis is inflammation of this sheath.
What are you doing to reduce inflammation?
Are you using a splint or removable brace to keep the tendon(s) still?
Surgery to remove the inflammation around the tendon may be used in some cases. I don’t believe it is a first option.
Did you have a cut or infection in the area?
If so, antibiotics are needed.
Are you seeing any improvements with what you have been doing?