Rouse left Michigan State's 38-14 victory over Western Michigan in the first half walking under his own power but did not return to the game.
Dantonio said the injury is to a vertebra in the neck. Rouse is expected to have surgery Saturday night.
Dantonio said Rouse has full movement.
Rouse is a senior from Newtown, Conn. He missed all of last season with a toe injury.