The United States Department of Defense (DoD) is funding exciting new research at the University of Texas Medical Branch (UTMB) Department of Orthopaedic Surgery and Rehabilitation that can be a major improvement in the treatment of extremity trauma involving segmental bone loss. These devastating injuries occur frequently in both civilians and the military. They typically result from motor vehicle accidents, high-energy fractures, gunshot injuries, and blast injuries, but also from the surgical removal of a bone segment because of infection or tumor. Despite many modern medical advances in this area, bone healing that can adequately replace bone loss and restore pre-injury limb function is extremely difficult to achieve. Existing standard treatment procedures are exceedingly complicated, require highly specialized equipment and clinical skills, and usually require many surgical procedures over many months or years. Despite these effort and costs, major complications usually occur with all the standard treatment options, the patient's ability to return to an acceptable functional status is typically low, and, therefore, many of these patients have their limbs amputated.