An apparatus for in-situ formation of a structural prosthesis includes a tubular member having a proximal end and an opposing distal end. A balloon having a compartment is disposed on the tubular member such that a curable biomaterial can be selectively delivered to the compartment of the balloon through the tubular member. A line is disposed on or in the wall of the balloon to facilitate at least partial severing of the wall of the balloon after the biomaterial has at least partially cured therein such that the balloon can be selectively removed from around the at least partially curedbiomaterial, thereby forming a structural prosthesis.