Can a soldier who just had PCL/ACL knee surgery be deployed?

If they are fully healed and can do their job within their permanent profile limitations, then yes.

I broke the top of my tibia 3 years ago, have pins and plate in my shin but can still pass the. ACFT with bike instead of running. I am deployable

Depends on their profile and Doctor/CO. If deployed would they be out in the boonies, damn doubtful, but in a semi-civilized area they could be CQ/radio watch, etc, while sitting down all shift.

If they just had the surgery, I doubt they would be cleared, medically, by SRP. It's possible they could be deployed to catch up to the unit after recovery and clearance from SRP.