According to Official Guinness Records,
The most points scored in a WFTDA Roller Derby power jam by an individual is 50 and was achieved by Megan Lazorski aka Slim Skatey (USA) for FoCo Girls vs Castle Rock at the First Bank Center, Broomfield, Colorado, United States on 27 April 2013.
Previous to this bout, a host of players had achieved 45 points but nobody had managed the half century until Megan Lazorski. Points are awarded to "jammers" when they pass their opposing skaters during the bout.
For a complete list of 2013 records, please visit 2013 Guinness Records in United States.