The Surgeons Who Make Toes Into Thumbs

Doctors look south to replace the king of digits.

Plastic surgeons are masters of rearrangement. Yes, they tuck tummies and build breasts, but it would be overly simplistic to think that’s all they do. They also restore the form and function of the body, pulling skin from one place to repair injury in another. They close cleft lips and reconstruct damaged faces using pieces of the body still intact. But sometimes, there is no easy replacement for a missing piece and no matching section of skin.

Take the thumb, for example. People who lose thumbs lose a digit that is key to opening doorknobs, grasping pencils, and picking up change. The thumb comprises up to 50 percent of our hand function, depending on the person and the doctor you ask. It’s an all-important finger, and its functionality determines the ease by which we live our lives. It’s the king of digits.

“The thumb is sort of what makes us human because it gives one of our key human functions, which is opposition,” said Dr. Joseph Rosen, a surgeon at Dartmouth-Hitchcock Medical Center.

There is no extra thumb on the human body, so plastic surgeons have had to look elsewhere, and their hunt has taken them south, to a procedure called a toe-to-thumb transfer, which is exactly what it sounds like. Taking someone’s toe and placing it on his or her hand might sound like fiction, but it is an example of a common surgical principle: Replace like with like.

Connecticut hairdresser Philip Colello lost his thumb in September 2013 when cutting wood on a table saw. He spent about six months without a thumb before undergoing the a toe-to-thumb at St. Francis Hospital in Hartford, Connecticut.

“It was more or less having to learn how to do everything without it,” Colello said about his time without a thumb. “It was a pain—just things around the house. Instead of having your hand to hold something, I had to clamp it. I was always dropping things. It’s just very awkward.”

The procedure that Colello underwent is far from the first of its kind, and yet a world apart from the early days of thumb replacement. In 1897 Austrian surgeon Carl Nicoladoni performed the first toe-to-thumb in humans by connecting a man’s hand to his foot at the base of the great toe. After the patient spent weeks bent over with hand locked to toe, Nicoladoni cut the great toe from the foot and left it attached to the man’s hand, thus creating the world’s first “thoe,” as they are sometimes now called. Nicoladoni’s patient was left without major nerves, but the doctor showed it could be done.

Today, surgeons around the country perform the same operation far more successfully—and without forcing the patient to spend weeks hunched over. Rosen has performed two dozen toe-to-thumb transfers since 1983. Now, a professor of surgery and associate professor of engineering at Dartmouth-Hitchcock, Rosen studied with Dr. Harry Buncke, known to many as the father of microsurgery, who performed the first microsurgical toe-to-thumb transfer on monkeys in 1966.

The surgery is becoming common, but not every hospital is experienced doing the transplant. Colello’s surgery was the first time any doctor at St. Francis Hospital had performed a toe-to-thumb transfer. Colello didn’t know that until his thoe generated buzz from local reporters and hospital employees.

“I took the procedure for granted,” he said. He had heard of finger transfers and figured this transfer was typical. He was hesitant at first but trusted his surgeon, Dr. Sam Buonocore, and the St. Francis surgical team.

Even with a minimum of four surgeons in the room, the procedure takes about eight hours. It requires two surgical teams—one that harvests the toe and another that prepares the hand for transfer. Though sometimes surgeons transfer the second toe, typically they opt to use the great toe. Once they have the toe off and the hand prepped, the transfer requires the use of microscopes to reattach the delicate corresponding nerves, vessels, tendons, and skin. Surgeons must connect the muscles used to flex and extend the thumb to those that flex and extend the great toe, respectively, and attach at least two nerves so that feeling from the toe communicates with the former thumb’s nerve.

Director of upper extremity transplant at Brigham Women’s Hospital, Dr. Simon Talbot, said the procedure “may be pinnacle of microsurgery for a microsurgeon.”

“There are many moving parts, when it comes to performing procedures as intricate as a toe-to-thumb transfer,” Dr. Alexander Spiess, division chief of hand surgery for the University of Pittsburgh Department of Plastic Surgery, said. “Fine details, such as how you angle your cuts on the bone, can impact the overall function of the thumb. Making a cut a few millimeters in one direction versus another can alter the overall function of the digit, emphasizing the importance of where you position the thumb in space with respect to the patient’s hand.”

Talbot noted that there isn't an easy analogy that explains the difficulty of the procedure, but said, "It is like sewing together a chopped chive with a human hair, but keeping in mind that the goal is to keep an open central lumen while ensuring that the juncture is water-tight."

And since many patients lost their thumbs due to trauma, the tissue that surgeons need to reconnect may not be easy to “hook up,” as Rosen phrases it. In some cases where the thumb was cut clean off, all of the necessary vessels are accessible to the surgeon. Burned, blasted, and crushed hands can make things more complicated.

“I had a kid in Vietnam that had lost all his fingers and he crushed his hand, so I had to hook up his toe. I had to go all the way into the wrist to find a vessel to hook up to,” Rosen said. In order to connect those hard to reach places, surgeons often use a long vein from the toe as a bridge. “But essentially, as long as the patient is alive there’s always a vessel to hook up to. I could always hook it up to the heart,” he said, smiling. “So we’re always going to find a vessel, it just becomes harder and harder.”

It’s not a perfect replacement. The great toe looks different than the thumb, and it functions in ways different than the thumb. And it’s not just the hand that has to heal, the foot does too.

“The worst part of it was taking the toe off,” Colello said, eight months after the procedure. “I lose my balance a lot easier. The foot is still healing. It’s still sore, whereas my hand isn’t. Even coming out of surgery, there was a lot more pain in my foot than in my hand.”

But with time and practice, thoes can become totally functional. Colello said that sensation has improved greatly—much faster than Buonocore expected. “It’s still numb. The feeling’s still coming back, so that’s a little awkward. It makes it feel even bigger,” Collelo said. “The only drawback is that the very tip of my thumb–or what’s replacing my thumb–doesn’t bend like my real thumb, my thumb I was born with.”

Colello noted that he could have another procedure that would allow him to bend his thumb, but that he wasn’t up for it right now. For now, he’s happy with the thoe he’s got and is hopeful that he will retain full sensation.

So while Colello’s thoe isn’t perfect, it’s better than nothing.

The toe-to-thumb transfer isn’t always the first option for people who lose their thumbs. When possible, doctors will replant the patient’s amputated thumb. A surgeon can also use the patient’s index finger to replace the thumb in a procedure called pollicization, which is commonly used for children with thumb abnormalities. If there is partial injury to the thumb, it can be refurbished, using tissue and cartilage from other parts of the body. When those options are deemed impossible or ineffective, surgeons turn to the toe-to-thumb transfer.

And the procedure has come a long way since that first 1966 monkey job. Most recently, doctors have worked on shaping and trimming the great toe prior to transfer. Dr. Fu-Chan Wei, a professor in the Department of Plastic and Reconstructive Surgery at Chang Gung Memorial Hospital in Taipei, Taiwan, has been working on a more conservative use of toe tissue. In his method, surgeons trim the outside tissue and sometimes bone of the great toe to make it more thumb-like in appearance and function. The trimming allows improved movement of the tip of the thoe that Collelo complained about. It also means surgeons can harvest less from the foot, which leaves the donor site, or the former great toe, in a less disabled form.

Wei reasoned that a great toe was functional but didn’t look like a thumb. The bulbous “thoe” might be a point of insecurity when patients shake hands with friends or coworkers. By trimming it, the thoe was less noticeable. Because of the improved appearance, people don’t feel like they have to hide it like a deformity.

“Appearance itself is part of function,” Wei said. “If [the patient] is concerned about the appearance, they would not have the maximum utilization of that function. This is the same principle that’s applied to the whole hand and all replacement surgeries.”

To date, Wei’s hospital has performed over 2,100 toe-to-thumb transfers. Since developing the trimming technique in 1980, he has transferred over 200 great toes and trimmed a great portion of them.

Colello said that no one notices that he’s got a thoe, and his toe didn’t need trimming. It was already a good size match.

“What I find myself doing is looking at other people’s feet and saying, ‘I lucked out. I got a decent looking toe,’” he chuckled. “I think a lot of people have really ugly feet.”

In the end, Colello is glad he went through with the procedure. There are some kinks to work out, he says, but doctors are on the job, thinking about how they can continue to better the procedure—or replace it.

In fact, the future of these transplants might not require the removal of a patient’s toe at all. Surgeons are experimenting with cadaveric transplants, in which they take a hand or forearm from a deceased patient and transplant it onto the patient in need of a limb. Talbot’s hospital has already performed two bilateral cadaveric hand and forearm transplants. Spiess’ hospital has performed five. There are challenges, like the body rejecting the new digit, but they are ones that the field is working to fix.

Spiess thinks that regular use of cadaveric parts is not so far off. “The field has evolved immensely in the last 10 years,” he said, “and I can see maybe within the next 10 years it becoming a routine art.”

And there are other, more fantastic possibilities in the works, as prosthetic technology improves. Talbot suggested a prosthetic thumb that combines steel, plastic, human nerves, blood vessels, and flesh.

“That’s sort science-fictiony, right?” he says. “You can imagine that as time goes by, prosthetics are getting closer and closer to being part of the human body. The hope would be that they become less of an external, wearable device and more part of you.”

Rosen has a different idea: Let’s just print a thumb.

“In 20 years, 40 years, 80 years, we’ll be laughing about toes,” he said about the toe-to-thumb transfer. He imagines a day when “we could take cells from you—fat cells or other cells—and convert them into critical tissue and use a 3-D bioprinter and print you a thumb, and attach it.”

Right now, the toe-to-thumb transfer is the peak of microsurgery, yet it may soon be just as archaic as Nicoladoni’s 1897 procedure. Surgeons master the status quo and then question it—it’s why the field of surgery is always evolving. To perpetuate innovation, they massage art into science.

“People often think that to be a plastic surgeon, you have to be artistic, that our operations are like creating a painting or making a sculpture because we’re molding a person’s body," Talbot said. "For me, the artistic aspect comes into the imaginative ideas, the left-field thoughts, the lateral thinking, and the innovative concepts.”

The future of plastic surgery, at least in the land of toe-to-thumb transplants, seems to rest somewhere in left field, and in artful surgical thinking.