Today, we straighten crooked bones. The University
of Houston's College of Engineering presents this
series about the machines that make our
civilization run, and the people whose ingenuity
Dr. John Gugenheim suits me
up and leads me into an operating room. The small
leg of a 7-year-old boy protrudes from surgical
linens on the table. His deformed foot bends at a
right angle. All his life he's limped about on the
side of that twisted foot.
Until now his deformity might've been altered by
conventional surgery, but it couldn't be
eliminated. "He's such a sweet boy," says the scrub
nurse readying his leg for a new kind of surgery. A
technician wheels in carts full of parts -- like a
big erector set. Gugenheim finds a 1/16-inch wire,
fits it into a drill, and begins.
He drills the pointed wire right through the skin,
muscle, and bone of the lower leg. He selects a
second wire and drills it through at right angles
to the first. He picks up two half rings made of a
carbon-fiber composite material --light and strong.
It's the same material they use to make stealth
bombers, but now we're repairing bodies, not
From the rings he fashions a wheel. The wires are
its spokes. He tensions them to 240 pounds. Now he
repeats the process at the ankle. Then he connects
the rings with adjustable rods, parallel to the
leg. Soon he has an external cylinder, anchored to
He calls this exoskeleton an external fixator.
Gavariil Ilizarov, a Jewish doctor in Siberia,
invented it in 1951. Ilizarov had to work far from
Russian seats of power, but his method nevertheless
managed to take root in Russia, then Italy. During
the mid-80s it reached the rest of Europe and
America. It's been widely accepted in the West only
since the 1990s.
I recently happened to meet an Azerbaijani
émigré -- a petroleum engineer. "Oh
yes," he said, "Ilizarov was my mother's relative.
We had many open fractures in the oil fields. After
Ilizarov surgery, workers walked again, right
away." I'd wondered what kind of magic this was.
Now I'm finding out.
Gugenheim works steadily for three hours. He
follows his own careful, but minimal, sketches
taped to the wall. He assembles some 150 parts into
a machine that encompasses the whole foot and lower
leg. It's equipped with screw adjustments and
He'll send the boy home in this device. The parents
will move the screws a quarter turn, a few times a
day, according to Gugenheim's specifications.
Ilizarov found that bone regenerates under tension.
This structure will slowly draw the bones out so
they can grow into a normal arrangement. The boy
will keep limping, but less and less each day.
He'll walk normally in six months.
I leave the operating room thinking about the
opera, Amahl and the Night Visitors.
Lame Amahl, visited by the Magi as they travel to
the manger, is miraculously healed. The word Magi
comes from the same root as magic -- and I have
seen the magic that will make this Amahl walk
I'm John Lienhard, at the University of Houston,
where we're interested in the way inventive minds