He collided with Steelers defenseman Matt Pergrave, whose leg came up and slashed Johnsons throat.
Johnson died later that night at a hospital.
Cut-resistant protective equipment was among the topics of discussion at the NHL General Managers meetings Tuesday in Toronto.
Nottingham Panthers forward Adam Johnson4000AndCounting/X
Screens were erected, and 8,000 fans asked to leave the area as his treatment continued.
Johnsons mother shared her sadness on social media, saying: I lost half my heart today.
