Henderson says in a statement of claim that he suffered a concussion and injuries to his neck and back.
He also claims he suffered shock, anxiety, depression, headaches and permanent and partial disability.
The Flames would not comment on the lawsuit when contacted Thursday.
Statements of claim contain allegations that have not been proven in court.
Henderson was hurt during the second period of Calgary's 2-1 loss to Nashville on Jan. 27, 2016.
Wideman was checked hard into the boards by Predators winger Miikka Salomak.
He banged his stick on the ice en route to the players' benches and could be seen shoving his stick into Henderson's back in front of the Predators' bench.
Henderson went down, but got to his feet and finished the game.
"I would never intentionally try to hit a linesman or a ref or anything like that," Wideman said following the game.
The NHL suspended Wideman for 20 games, which was later reduced to 10 games by an arbitrator.
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