Thank you very much for replying :)! That helps!
The pin is unlikely to be removed in future. Also the movement is unlikely to improve after arthrodesis. I would suggest getting the pain evaluated by your orthopedician for secondary causes such as contractures, nerve impingement/ pressure, vascular insufficiency, infections, inflammations, degenerations, fractures etc. After a cause is diagnosed, it can be managed accordingly.
Hope this was helpful.