Kukan suffered a medial meniscus tear and articular cartilage injury during Thursday's game against Boston and is considered out indefinitely.
With Kukan set to miss extended time, Gabriel Carlsson should get an opportunity to hold onto a regular spot in the lineup, at least until Markus Nutivaara (upper body) is cleared to return. The 26-year-old's absence won't impact any fantasy owners, as he's only picked up five points while posting a minus-9 rating in 33 games this campaign, but it will undoubtedly test Columbus' blue-line depth. He'll be placed on injured reserve until he's ready to rejoin the lineup.