Scientists at the Medical University of Vienna, some of the world's foremost experts on limb reconstruction among them, created what they call the world's "first bionic bird" in 2018 by designing a prosthetic appendage for an atypical client: a then 1-year-old bearded vulture named Mia.
Born in captivity, Mia suffered a serious injury when she was a small chick, according to the Vulture Conservation Foundation. Some of the wool fibers her parents had incorporated into their nest became wrapped around her right foot, starving the individual toes of oxygen. Left with no other choice, staff at her birthplace, the Richard Faust Zentrum Specialised Breeding Centre, amputated the foot, impairing Mia's ability to fly and feed normally.
Like all vulture species, bearded vultures rely on their powerful legs to hunt and propel themselves into the air, so the loss of one is all but a death sentence, according to Live Science. Feet "are vital tools for a vulture, not only for landing and walking but also for holding their prey, so...their feet have to withstand various loads," veterinarian Sarah Hochgeschurz, DVM explained in a statement issued by MedUni Vienna. Once it became clear that Mia "could not survive long" in her "current condition," reconstructive surgeon Oskar Aszmann, MD said in the statement, he and several other stepped in to lend a hand at Hochgeschurz's bequest.
While Aszmann and his colleagues had developed custom prosthetics for human beings before, they had never before attempted to treat a wild animal. The task tested the limits of their creativity and medical knowledge. First, the prosthetic had to be sturdy enough to absorb the shockwaves that result from landing. Second, it had to be dexterous enough to allow Mia to seize both prey animals and perches.
Their solution to the problem relied on a novel orthopedic technique known as osseointegration. For those readers who took Latin in high school or college, it's exactly what it sounds like; for those who didn't, it involves installing a foreign object in bone. In Mia's case, the foreign object was a metal anchor that attached to a small cylindrical slab of black rubber. While the slab, which is dirt-repellent and waterproof, does not resemble a typical bird foot, it meets Mia's basic flying and feeding needs, according to Live Science.
In May 2018, per the Foundation, the team sedated Mia and installed the anchor over an hour and a half. While surgical operations and their aftermath can be extremely stressful for wild animals, Mia recovered well overall. Within four weeks, she was making attempts to walk again; within seven, she was putting all her weight on the prosthetic, Aszmann said in the statement.
"Today, the bearded vulture can once again land and walk using both feet, making it the first 'bionic bird,'" he said.
The team's description of the surgery was published on June 11 in the journal Scientific Reports.
