The 25-year-old has not played for the Tykes since his failed move to Premier League side Huddersfield Town in August.
He made two appearances for Barnsley this season, adding to his 32 league outings last campaign, before leaving for a mysterious medical at the Terriers.
"He [Yiadom] has been out a while now and we have followed everything that the specialist has said and it is pointless then for him to be doing things off his own back," Heckingbottom told the press.
"He has got a check-list of things to hit before the specialist is happy with things.
“Sedgy [physio Craig Sedgwick] has a programme he has set out for Yids, which he has condensed into a small timeframe as possible. I know he is chomping at the bit to be involved as much as possible.
“But it is dependent on what the scans say, although we are expecting them to be good and then for him to rattle through his rehabilitation programme fine.
“Hopefully, we are looking at a couple of weeks before he is back in training.
“Realistically, with the length of time we have done without him, we want to make sure he is right.
"We will use the (next) international break to his advantage if we can.”
Yiadom was in action as the Tykes succumbed to a 3-1 defeat to Bristol City in the Championship opener on August 5, before seeing another full-time action in their 4-3 League Cup win over Morecambe three days later.
The London-born, who has two caps for Ghana, joined Barnsley from Barnet in summer last year.