Levy suffered an injury in the same knee last season.
Levy played in just six games the past two seasons after signing a big contract in 2015. Birkett notes that Levy had a $1.75 million injury guarantee in his contract, which the Lions avoided by releasing the linebacker. The issue could lead to a grievance now that he underwent another surgery.
The knee issue could explain why the former havoc-wrecking linebacker hasn't seen a sniff of interest on the open market since being released.