Shrews are down to 18 fit first-team squad members - four of whom are first-year professionals - with Disley, Omer Riza, Chris Neal, Glyn Garner, Michael Jackson and Terry Dunfield all sidelined.
However, the signs are positive for Disley after scans on Tuesday morning revealed he only suffered Grade One damage to knee ligaments during Saturday's win at Accrington, although he will be out for a short period.
Simpson, who also discovered Neal should return in the middle of September with his groin injury improving, told the club's official website: "The original fear was that Craig would be missing for over a month so the results are some good news.
"It is a blow, though, to have another player missing through injury and I'll have to look at whether or not we need to strengthen ahead of the transfer window closing."
Meanwhile, it has also been confirmed Labadie, who penned an initial month-long loan deal at the start of August, will now remain with the club until the turn of the year, although West Brom do have a recall option.