The American Orthotic Prosthetic Association, a national trade group, has promised to provide artificial limbs to any people who lost a leg in the Boston Marathon bombings if they are uninsured or their insurance fails to cover the cost.  More than a dozen people lost limbs in the blasts; it is not yet known how many will need help paying for prostheses. The cost of an initial prosthesis could be $8,000 to $30,000, said Tom Fise, the group’s executive director. Many insurance plans sharply limit coverage, he said.
