McDonald is an Indianapolis native and played his college football at Indiana University, where he started 25 games. He wasn't selected in the 2012 NFL draft but was signed by the Miami Dolphins as a free agent.
McDonald, 26, was diagnosed with testicular cancer in May while he was with the Carolina Panthers. He was signed by the Seattle Seahawks off the Panthers practice squad in September and appeared in two games, playing on special teams before being released Nov. 26.
The Colts waived tight end Weslye Saunders in a corresponding roster move.
Indianapolis head coach Chuck Pagano is also a cancer survivor. He was diagnosed with leukemia in October 2012, forcing him to take time off from his coaching duties until he returned in December of that year.