Westbrook also committed six turnovers and has now turned the ball over 12 times in the last two games.
The Thunder shot 52.0 percent from the floor and were 10-of-17 from three-point territory as a team while holding the 76ers to just 40.5 percent shooting from the field.
Kevin Durant, Kevin Martin and Serge Ibaka also scored in double-figures for the Thunder as they had 26, 16 and 15 points respectively.
Jrue Holliday led Philadelphia with 15 points and nine assists on 7-of-13 shooting from the field.
The loss was Philadelphia's second in a row as they fell to 15-19 on the season. Oklahoma City improved to 25-7 with the win.