 Chronic knee problems plagued Orr throughout his career . In 1972 , he tore ligaments in his left knee after a hard hit , leading to the first of six knee operations . He played 12 seasons in the NHL before injuries forced his retirement in 1978 . Orr finished with 270 goals and 915 points in 657 games and won the Hart Memorial Trophy as the league 's Most Valuable Player three times . The customary three @-@ year post @-@ retirement waiting period for entry into the Hockey Hall of Fame was waived as he was enshrined in 1979 . 
