 In September 1978 Mantis was injured in an industrial accident, losing his left arm.Before 1996, Mantis was an employment services manager in the Thunder Bay Regional Office of the Ontario March of Dimes during a time of transition for the organization into one providing modern vocational training.Since 2004, Mantis has been the community co-lead in the Community-University Research Alliance on the Consequences of Work Injury with McMaster University.