In his first full season in the NHL, he became the first player in history to spend 200 minutes in the penalty box in a single season. Nowadays if a player gets 200 minutes he's considered to be a power forward or a monster on defense. In 1956, 200 minutes in penalties was unthinkable.
Although Fontinato is remembered for being a tough guy and for leading the league in penalties no less than 3 times (and was runner-up another 3 times) in his 9 year career, often forgotten is the fact that he was a very solid defensive defenseman. Fontinato scored 26 goals and 78 points in 535 NHL contests. He added 2 more assists in 21 playoff games.
"Leaping Louie" is often thought of for losing one of the most famous fisticuffs in NHL history. On February 1, 1959, Fontinato came to the aid of teammate Eddie Shack, who was being tossed about by the living legend Gordie Howe. Louie quickly challenged Mr. Hockey and connect with three huge blows before Gordie had a chance to counter. But when Gordie endured the heavy punches, he countered with one of the most one-sided assaults in an NHL fight. Howe pounded Fontinato with several quick piston-like jabs, severely breaking Louie's nose and sending him to the hospital.
In the summer of 1969, Fontinato was dealt to Montreal in exchange for one of the all time greats in NHL history - Doug Harvey. Harvey's best days were by him by this point. But Fontinato would terrorize NHL opponents for two seasons with the Habs.
Fontinato's hockey career was shortened by one of the most horrific injuries in NHL history. The accident happened on March 9th, 1963, ironically against the New York Rangers. Fontinato and Vic Hadfield crashed into the boards while chasing a loose puck. While Fontinato ducked out of the way of Hadfield's elbow, he ended up smacking his own head against the boards. Fontinato suffered a badly broken neck and never skated again.