Muletas de Cartulina

Cardboard crutches are Michael Joynt's answer to expensive crutches found in most hospitals. His design costs roughly 2.75 pounds and is made of

convolute cardbored cores wrapped in Poly Propelene plastic and rubber pushlift parts

I wonder if this is the same stuff found in the cores of fax spools and such...would that be strong enough? These cores can be pretty tough...other's like Japan's Shigeru Ban have made houses and other structures. What else can you come up with?

Tags: assistive, design, paper, crutches