The 49ers have yet to publicly disclose the nature or severity of Dorsey's injury, though ESPN.com reported that the six-year pro is expected to undergo surgery Monday and would likely be out for all of 2014.
According to Comcast Sports Net Bay Area, Dorsey will be evaluated over the next few days before the team determines whether or not he will require surgery.
Dorsey joined the Niners in 2013 on a two-year contract and switched from defensive end to the interior of the line. He started 13 of the 16 games he played last season and notched 41 tackles with two sacks.
The 29-year-old LSU product spent his first five seasons in Kansas City after the Chiefs made him the fifth overall pick of the 2008 draft. He has 279 career tackles and six sacks in 82 NFL games, 78 of which have been starts.
Dorsey was elevated to the starting lineup after fellow nose tackle Ian Williams sustained a fractured ankle and ligament damage in Week 2 of last season. Williams has yet to practice thus far in training camp and is currently on the active/physically unable to perform list.