Hi,
You seem to be pretty clued up with regards to the balance and proprioception but what are you actually doing with the wobble board?
You really need to challenge your balance and proprioception after such an injury to get back to sporting fitness, and simply wobbling about with both feet on the board really won't do much for someone expecting the performance I assume you do from your joints!
Speak to a physio who can advise you on progressions of the exercises and show you others which can help challenge your balance even further!
Good luck and please don't hesitate to contact me if you'd like further information.
Ruth Cheesley BSc(Hons) MSc MCSP
Chartered Physiotherapist