Joe Theismann – Retired at 36 in 1985
This injury is one of the most well-known, and notoriously gruesome injuries in NFL history. Under head coach Joe Gibbs, Joe Theismann enjoyed a late-season renaissance, being named to the Pro Bowl in 1982 and 1983, and guiding the Redskins to three straight playoff appearances from 1982 through 1984 (which included two Super Bowl appearances).
But in a mid-November game against the New York Giants, Hall of Fame linebacker Lawrence Taylor was in the process of sacking Theismann when Taylor’s knee came down and drove straight into Theismann’s lower right leg, snapping right through Theismann’s tibia and the fibula. The injury was so horrific that Taylor began to scream for medical personnel to help Theismann. The compound fracture to Theismann’s leg forced him into retirement.