NFL Media Insider Ian Rapoport reported Houston is progressing well in rehab and is off crutches.
The optimistic recovery time would put the Pro Bowl linebacker back in mid-August by the earliest. He will likely spend training camp on the physically unable to perform list.
Houston could be a candidate to begin the 2016 season on the PUP list, which would sideline him for the first six games of the season.
Houston missed the final five games of the 2015 regular season with a PCL injury. In his return for two playoff games, the linebacker never looked like himself. He was tentative at the point of attack, lacked burst and appeared to slow several plays.