Photography by David Torrence
One Saturday last summer, noted florist Walter Knoll was at his office doing some woodwork. As he made a cut with a tool called a biscuit joiner, his hand slipped, and he badly severed his left thumb. The blade sliced diagonally from the right edge of his knuckle to the left side of his fingertip. “It didn’t bleed really bad, and it didn’t hurt bad,” Knoll says. “It felt like a searing burn for just a split second. My thumb still worked and moved, but this piece was hanging off.”
He rushed to the emergency room at Saint Louis University Hospital, where doctors used about 100 stitches to sew the thumb back together. The most disconcerting moment for Knoll came when he heard them discussing the amputee in Room 6. “I realized I was the amputee,” he says.
Knoll works with his hands, but his first concern wasn’t flowers; it was the piano. He used to play two hours a day and worried that he might never touch the keys again. But his thumb, which had turned gray, began to pink up. Maybe it could still be saved.
That hope vanished a few days later, when he got his cast off. “It looked like the mummy toe at the museum,” the florist says. “It was black and horrible.” That’s when Dr. Bruce Kraemer, the director of plastic surgery at Saint Louis University Hospital, offered Knoll a second opinion. As Kraemer describes it, Knoll’s thumb was “just a big old mangled mess.” They decided to remove the dying end. “That was a little traumatic,” Knoll says.
At that point, they turned to a technique from a relatively new field called regenerative medicine. The treatment sounds absurd: Knoll would sprinkle a white powder, looking a bit like Parmesan cheese, onto the surface of his thumb once every day or two, and the thumb naturally (perhaps magically) would grow back much of the lost tissue. It’s expensive stuff, so Knoll applied it over a glass plate, to ensure he didn’t lose a single granule.
Of course, the powder isn’t really cheese. In fact, it’s a pork product, derived from a structural layer of pigs’ bladders. It works in various ways. First, it prevents scar tissue from forming. As the body’s reaction to an injury, scarring can be a good thing. It’s healing done fast—just not always well. Heading it off gives the body time to rebuild in a way that’s more like the original.
The powder also promotes regrowth by providing some of the building blocks—collagens and proteins—needed in the healing process. As the body transforms those elements into new flesh and bone, the pig-bladder material disappears, becoming part of, in this case, Walter Knoll’s thumb.
Today, if you look at Knoll’s hand, it’s still apparent that he suffered an injury. But he’s regained nearly full use of the thumb. He has little pain and no swelling. “I know this doesn’t look real good, but I have a fingerprint there,” he says. “That would be unheard of.” And he’s back to playing the piano. “I’m blessed that I got called,” Knoll says of Kraemer’s offer of a second opinion. “Honest to God,
I thought there might be divine intervention.”
