The Lions signed offensive tackle Jonathan Scott and released Johnny Culbreath.
Scott was released by the Steelers last week and enters his second stint with the Lions. He started 14 games in two seasons in Pittsburgh.
Culbreath was a seventh-round pick in 2011 and spent his rookie season on injured reserve with an undisclosed illness. He was arrested in January for marijuana possession, one of seven offseason arrests for the Lions.
Scott, 29, was a fifth-round pick of the Lions in 2006.