Prior to surgery my core was already pretty strong. Since I resumed working out since surgery I'm finding that my core isn't as strong as it used to be. Do you think that it's due to they surgery?

You took a month off before doing core work, so it will come back. You did take a month off right? You got 5 incisions, and while they were small they still cut through muscle and connective tissue, it takes some time for that to heal.

Thanks. That gives me hope!