A retired Army Veteran was injured by a rocket propelled grenade (RPG). Due to the shrapnel and dirt that entered his wound, he suffered multiple infections and endured 24 surgeries.  He finally elected to undergo a right leg above the knee amputation to lessen infection and improve function and recently had osseointegration surgery. Mountain biking is an integral part of his physical and mental health, and quality of life.  The Challenge is to create afunctional, safe breakaway system for his osseointegrated prosthetic leg attachment so he can safely continue his activities.