Blackburn, 31, was injured in Carolina's Week 6 tie against the Cincinnati Bengals and missed the team's last two games. He started two games and recorded 12 tackles and a forced fumble for the Panthers this season.
This was Blackburn's second season with the Panthers after playing the first eight seasons of his career with the New York Giants. He will be a free agent after this season.
The Panthers also waived running back Darrin Reaves on Monday. While filling in for several injured Carolina running backs, Reaves had 32 carries for 77 yards in six games, including one start.
Carolina filled the two roster spots with offensive tackle Mike Remmers and safety Robert Lester. Remmers was previously on the St. Louis Rams' practice squad, and Lester was promoted from the Panthers' practice team.
The Panthers missed starting offensive tackles Byron Bell and Nate Chandler for chunks of their loss to the Seattle Seahawks on Sunday. Defensive backs Thomas DeCoud (hamstring) and Bene Benwikere (ankle) are also banged up.
Carolina is in first place in the NFC South at 3-4-1. The Panthers host the Saints on Thursday night.