A group of veterinary surgeons is learning how to transform simple pieces of metal and plastic into working feet, legs and tails. What doctors are learning about animal prostheses could help them improve human prostheses, as well. Both human and animal prostheses need a makeover. Typically, the stump of a damaged limb is inserted into the socket of a prosthesis and held by a plastic sleeve or belt, or suction. Over time the prostheses have gotten lighter and more flexible, but the stumps' socket attachments can be unstable and cause the breakdown of soft tissues, as constant rubbing leads to pain and infection. Animals are worse off -- if prostheses exist at all, they have been crude contraptions at best.

Winter, a dolphin at the Clearwater Marine Aquarium in Florida is completely tailless because of an injury incurred by a crab trap. A sticky, gel-like substance was used to hold a prosthetic tail in place. The gel also lubricates just enough to help protect against irritation. The same gel was given to a soldier who had been suffering from recurrent infections due to his prosthetic leg. Because of the gel, his skin cleared up.

Closer to home, Steve Hoover, a prosthetist at Wright & Filippis' Ann Arbor facility, was approached by Brad Pearsall, a physical therapist at Rainbow Rehabilitation Center, where a 6 year old dog named Footsie works as a certified therapy dog. Footsie was born without paws on his hind legs, and Brad thought Steve could make the dog some prosthetic paws.

That's when Steve asked Ken Woodard, an orthotist at Wright & Filippis' Ann Arbor facility, for help on the project, since neither of them had ever done anything like this before. Steve and Ken spent nearly a year working on making the prosthetic in their spare time. Using a process called vacuum-forming, the prostheses were made by shaping a layer of foam and a layer of plastic over a mold of the dog’s legs. Then a hard, black shell with tread material on the bottom was added. The shell is fastened to the dog with a Velcro strap. "It took a long time. There was a lot of trial and error, but I think we finally got it right," said Steve. Footsie's owner, Helen DePinto said that when Footsie tried them on, it was a "home run."

When Motala, an elephant, stepped on a land mine in Thailand eight years ago, the outlook was bleak. An operation saved her life but left her hobbling around on three legs for six years. Finally, in 2005 surgeons in Thailand, designed a 22-lb. shoelike prosthetic foot, basically a canvas sack filled with sawdust and held in place by a giant sling. But, cases like Motala’s have inspired surgeons to begin experimenting with new, radical approaches that could potentially transform the field of prosthetics. One method known as ingrowth, or osseointegration, skips the sleeves and cuffs and attaches the prosthesis directly to the bone. It works by inserting a porous metal implant straight into the end of the remaining bone. Over a few months, the bone grows around the implant, providing a strong anchor onto which a prosthesis can be attached. Scientists are also finding that softer muscle and skin tissue will also grow into the pores and help prevent infection by producing a bacteria-resistant seal. Osseointegration has worked for at least 6 animals and has been attempted in at least 60 humans.

Currently there are around 1.9 million amputees living in the U.S., that’s expected to jump to 2.7 million by 2020 -- mainly because of wounded soldiers returning from the war in Iraq and patients who lose limbs to diabetes-related complications. These advances in prostheses couldn't come at a better time.