The team said then that its franchise quarterback suffered a concussion, but the Pittsburgh Post-Gazette reported on Monday that the injury was more serious.
Roethlisberger suffered a spinal cord concussion, and he called it "scary" when he could not feel team doctors sticking a pin into his arm on the field.
The quarterback was tackled by two Browns defenders and appeared to hit his head on the turf. His face mask was removed, he was placed on a spinal board and carted off the field. At Pittsburgh's Presbyterian Hospital, he quickly regained feeling in his arms and was later released. The newspaper reported that he never lost feeling in his legs.
According to the Post-Gazette, Roethlisberger passed all of his follow-up tests for concussions.
He returned to the field for a playoff game on Sunday and passed for 181 yards and a touchdown, without an interception, in the Steelers' 35-24 win over the San Diego Chargers.