Frankenstein's Cat: Cuddling Up to Biotech's Brave New Beasts (17 page)

So are Neuticles really for dogs? Or are they for humans, a way for us to atone for the castrating we put our pooches through? Most of his customers, Miller says, are “freaking out over neutering their dog.” The possibility of testicle implants soothes their psychic pain, and some animal welfare groups have endorsed Neuticles because they may spur pet owners who are on the fence about castration to go ahead and get their pets fixed.
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(In fact, when Miller heard that President Bill Clinton had expressed hesitation about neutering Buddy, the First Dog, he did something that required both literal and figurative
cojones
; he asked the leader of the free world to give some thought to a prosthetic package.)

I never considered Neuticles when I got my dog, Milo, neutered, perhaps because I’m a woman. According to a survey of nearly sixteen thousand Australian dog owners, men are twice as likely as women to believe that neutering fundamentally changes a dog’s “maleness.”
^†
It occurs to me that Neuticles might be a lot like truck nuts, those fake plastic testicles men sometimes affix to the back of their vehicles—there to telegraph the virility and manliness of the owner. Indeed, one male customer reported that his only disappointment with Neuticles was that he and his wife hadn’t gotten their dog a bigger size. According to one scholar of gender studies and human-animal interactions, “many men continue to view their male pets as personifications of their own egos and libidos.”

Though Neuticles are a bit, well,
nutty
, they don’t strike me as cruel. Especially when we compare them with some of the other things we do to dogs’ bodies. Take tail docking, for instance, in which the last several inches of a puppy’s tail are removed, usually without anesthesia, sometimes with extremely crude instruments such as scissors or razors. The American Kennel Club (AKC), which develops guidelines used to judge canines in competition, prefers boxers, rottweilers, cocker spaniels, and dogs belonging to dozens of other breeds, to have docked tails.
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In other words, an ideal specimen is one that’s been surgically reshaped by humans.
^†

Speaking of surgery, some vets are now giving dog owners the opportunity to have their pooches nipped and tucked. Pet plastic surgery can have a medical rationale—nose jobs can make it easier for some breeds (such as pugs) to breathe, face lifts can eliminate folds of skin that trap bacteria, and doggy braces can alleviate sores caused by crooked teeth. But one veterinary surgeon in Brazil says he has no problem performing the procedures for purely cosmetic purposes. “Why shouldn’t a dog be beautiful?” he told the BBC. “Beauty is desirable. We all like talking to someone who looks good and smells nice. It’s the same with dogs.” But does the search for beauty alone, especially in the eye of a human beholder, really justify putting these canines under the knife?

Neuticles provide another way for us to project our own aesthetic ideals onto our pets, but the false balls also represent something more complicated than that. While few would argue that docking a cocker spaniel’s tail makes the animal happier, hundreds of thousands of customers think synthetic testicles are good for their dogs. (One pet owner’s silly silicone sac is another’s medical miracle.) Neuticles—and the strange mixture of motives that may prompt their purchase—illustrate how hard it can be to untangle our own interests from what best serves an animal.

*   *   *

Even Carroll, who says his work is motivated purely by a love of other creatures, faces critics. But he is undaunted by those who say that animal prostheses are a waste of time and money. “We try to work around positive people [who] think there’s options out there, that there are solutions that can help an animal get back up and walk again,” he says. “I think it’s critical to take care of our animals and to help rehabilitate them when they get injured. Mostly the ones that we see, it’s humans that have injured them, and I think it’s important that humans put them back together.”

Carroll and his colleagues have worked with animals for whom prostheses have been lifesaving. After Winter’s story appeared in a local newspaper, Carroll got a call from Lee Fox, who runs Save Our Seabirds, an avian rescue and rehabilitation facility in Sarasota, Florida. Sandhill cranes commonly come into Fox’s care; the birds are often hit by speeding cars and wayward golf balls, irreparably damaging their delicate legs. Because of how the birds are built—with long, thin legs and big, heavy bodies—a crane with a bum leg is usually a crane that will be euthanized.

Fox was, she says, “truly, physically sick about having to put down one sandhill after another,” so she began outfitting her birds with prostheses she jury-rigged out of some PVC pipes and sink stoppers. When she met Carroll, he fashioned a more comfortable, permanent solution, taking plaster casts of the legless birds and making prostheses out of lightweight plastic. The recipients included a crane named Chrisie, and Fox vividly recalls the day Carroll first put his device on the bird: “Chrisie walked in hers like it was her own leg.” The birds even use their artificial limbs to scratch themselves, something healthy cranes do with their natural legs. As Carroll notes, “Animals are wild, so they’re very adaptable to their situation. We help them and they get along with their little lives.”

Cranes aren’t the only creatures that could be saved by a well-engineered false limb. Horses are usually put down when they break or seriously injure a leg, and while some dogs career around just fine on three paws, not all adapt as easily. A corgi, for instance, with its long, tubby body, can’t manage on three legs, says Noel Fitzpatrick, a veterinary orthopedic surgeon with his own practice in Surrey, England. Fitzpatrick thinks vets have been too willing to euthanize pets facing the loss of a limb. “Animals deserve a good quality of life,” he says. “I’m not saying that you shouldn’t put a dog to sleep if there’s no other option. But there are circumstances, lots of them, where prosthetics really should be used.”

There’s especially no excuse today, he explains, given the advances in veterinary and materials sciences that are giving injured creatures more options than ever. Feline and canine anatomy present unique challenges for prosthetists—just as Winter’s body did. Though dogs and cats
can
wear devices that strap on to the outside of their bodies, they don’t always do well with them. Below-the-knee amputations in these species don’t leave much muscle or flesh for an external apparatus to grab on to, and their rounded bones are difficult for an artificial limb to grip. Above the knee, the animals have too much muscle, and lots of loose skin, surrounding their bones; even when a socket prosthesis is tightened all the way, cats and dogs can sometimes pull their legs right out. What’s more, pets often kick, chew, or claw off a strap-on device.

Fitzpatrick has been pioneering an alternative kind of prosthesis that gets around many of these difficulties.
*
His approach, known as osseointegration, involves implanting one end of a prosthetic leg in an animal’s stump and fastening it to whatever bone is left. The metal implant then passes through the skin and can be attached to a specially engineered foot or paw, creating what Fitzpatrick calls “a bionic dog.”

Fitzpatrick knew that osseointegration was not without risks: A bone-anchored prosthesis breaks the skin barrier, jutting out through a patient’s stump, providing an easy entrance for bacteria and leaving the patient susceptible to serious infections. Fortunately for the vet, Gordon Blunn, a biomedical engineer at University College London, thought he had a solution to this very problem. Blunn believed that surgeons could learn from deer antlers, one of very few cases in nature where skin and bone are tightly bonded. The secret to this strong marriage, one of Blunn’s graduate students discovered, is that antlers are covered with tiny pores. Collagen fibers grow into and through these openings in the bone, creating a permanent connection between the antler and the surrounding skin. A pore-pocked prosthesis that mimicked deer antlers, Blunn proposed, might interface with the skin to create a protective seal against infections.

Using antlers as inspiration, Fitzpatrick and Blunn designed a medical device for legless animals: the intraosseous transcutaneous amputation prosthesis, or ITAP. By 2007, they were using it in pets. One of the first patients was an American bulldog named Coal, who had a tumor in his front left paw. The normal treatment would have been full amputation of the leg, but Coal had arthritis in his other limbs and was likely to struggle as a three-legged dog. So Fitzpatrick agreed to give Coal an ITAP. With the dog under anesthesia, Fitzpatrick inserted a rod made of a titanium alloy into the center of what remained of Coal’s radius. As the rod emerged from the bone, it opened up into what resembled an upside-down umbrella. Fitzpatrick stretched Coal’s skin over this rounded cap, which was dotted with small holes, much like a deer’s antler. Then the surgeon sewed the bulldog up, hoping that Coal’s soft tissue would grow into and through the implant, creating permanent links between skin, metal, and bone. Fitzpatrick left a short segment of titanium jutting out from Coal’s stump, into the open air. When the dog’s wound healed, his owners could then pop an artificial paw on and off the metal rod.

The antler-inspired device worked—Coal’s tissues gradually grew into the implant, forming a sturdy seal, and there were no signs of infection. The bulldog adapted beautifully to his new leg. “The ITAP didn’t just improve Coal’s quality of life, it gave him life,” his owner wrote in a testimonial. “Coal led a perfectly normal life after the operation, there was absolutely nothing he couldn’t do. He would use his prosthetic leg to bash at the door to be let out, and used it with his good paw to hold food and toys, as well as give you his ‘paw’ when he wanted a treat. The most amazing thing was people never noticed he had a prosthetic leg until they actually looked closely.”

Coal has been followed by other successes, including a black cat named Oscar, who received two ITAPs after losing both his back paws in an unfortunate run-in with a mechanical grain harvester. Fitzpatrick, who was the subject of a documentary series called
The Bionic Vet
, estimates that he’s done about two dozen of these animal ITAPs. The procedure has been so successful in animals that human trials of ITAPs are under way in Britain. (One of the first recipients was a woman who lost her arm during the July 2005 bombing of the London Underground.)

Fitzpatrick’s technique is just one approach to osseointegration, and a handful of other vets are trying out their own variations. Denis Marcellin-Little, a veterinary orthopedist at North Carolina State University, has a number of canine patients that are either overweight or very active and thus not good candidates for conventional, strap-on prostheses. With osseointegrated devices, Marcellin-Little has helped some of these formerly hopeless cases get back on their feet again. Meanwhile, one equine researcher is designing implants that could be used to build bone-integrated prostheses for horses; the devices might save the lives of racehorses such as Barbaro, the Kentucky Derby champ who had to be euthanized after breaking a leg and suffering from an escalating series of complications. (Veterinarians tried to repair Barbaro’s leg, but it didn’t heal well, causing additional strain on his good legs. Eventually, these limbs, too, began to break down, leaving the horse literally without a leg to stand on.)

Animal prostheses, and the research and development required to create them, are not cheap, and Fitzpatrick says he’s sometimes asked why he’s spending so much time and energy designing a leg for someone’s dog. The endeavor is about more than just giving a pet a new limb, he says. “It’s about life and love. It’s about the bond of love between an animal and a human that is a small microcosm about how things could be better on Earth.”

Osseointegration is also a step toward building an even more futuristic kind of prosthesis—one that is not only a permanent part of the body but also works seamlessly with the nervous system. With such devices, patients will be able to move manufactured limbs more like natural ones, wiggling carbon-fiber fingers or toes just by thinking about it. There have already been major breakthroughs. Monkeys outfitted with brain implants have been trained to use just their thoughts to move external robotic arms—in one case, using an arm to feed itself marshmallows—and paralyzed humans have performed the same feat. (Instead of eating marshmallows, the human volunteer used the robo-arm to give his girlfriend a high five.) Scientists at the Rehabilitation Institute of Chicago have succeeded with a different approach, taking the nerves that would normally control the movement of a missing arm and moving them into the muscles of the chest in several human amputees. Patients learned to use the nerve signals generated by the use of these muscles to control virtual arms on a computer screen, as well as motorized prosthetic limbs.

The main goal in developing these robotic limbs has been to improve the lives of human amputees or quadriplegics. In particular, the Defense Advanced Research Projects Agency (DARPA), part of the U.S. Department of Defense, has invested a lot of time and money in this area of research, hoping to find better solutions for injured veterans. However, just because animals aren’t the
intended
beneficiaries of this work doesn’t mean that they won’t benefit along the way. Prosthetic innovations flow back and forth across species lines, and it wouldn’t be surprising to see scientists refining nerve-integrated prostheses in injured animals or veterinarians borrowing tools and techniques being used in human patients. A variety of diseases and conditions cause hind leg paralysis in elderly dogs, for instance; by turning these canines into cyborgs, with brain-controlled prostheses, we could give them back control of their nervous systems.

Or we could do something even more extreme, building bionic animals and then taking control of their nervous systems ourselves.

7. Robo Revolution