The increasing number of people who are living longer and have afar more active lifestyle is inevitably associated with greater numbers of fractures. Stabilization of these fractures in older patients with plates and screws is complicated by fragile bone substance, especially in osteoporotic bone, since osteosynthesis with aconventional plate depends exclusively on the holding power of the screws. Therefore, treatment requires new stabilization technologies designed for these specific tasks. Asmall diameter polyethylene terephthalate (PET, Dacron®) balloon is delivered in aminimally invasive fashion and placed within the canal, transversing the fracture. Once positioned, the balloon is expanded with aliquid monomer to fill the medullary canal. The liquid monomer is then rapidly cured using visible blue light, forming apatient-customized intramedullary implant that stabilizes the entire length of the bone in contact with the implant. The described intramedullary implant can be easily drilled in any position or location, providing asubstantial increase in screw holding power. Thus, a major advantage of the technique is the possibility to augment the newly formed balloon "nail" with aconventional plate and screws at the primary stabilization or at any later time.