Medical Inventions of Memphis

Medical Miracles

by Devin Greaney and Terre Gorham
From the MEMPHIS DOWNTOWNER October, 2008

TOC: Memphis has produced a lot of genius, from world-changing music
legends to globe-impacting entrepreneurs. Add medical innovators to
the list.

With its headquarters in Memphis’s biotech district, Luminetx Corp.
made waves in 2004 with its creation of the VeinViewer Imaging
System. Those hard-to-find blood vessels zigzagging through the
network of our circulatory systems became easy to quickly spot for
immediate access to life-saving injections. And as incredible as this
invention is, Luminetx is hardly alone in Memphis medical innovation.
The inventions created by Memphians have made dramatic impacts felt
around the world in treating the sick and injured.

Here are just a few …

Sam Splint

The most well-known resident of 1408 Rayner Street in Memphis was
George “Machine Gun Kelly” Barnes, who was captured in Memphis
there in 1933. But perhaps it should be better known as the childhood
home of Dr. Sam Scheinberg. Never heard of him? He just might have
helped you.

As an Army medic in Vietnam from 1968 to 1969, he saw the need for a
better splint for broken bones. One case that sticks in his mind
involved a soldier who arrived via helicopter for treatment. “He had
a burn and a broken arm,” Scheinberg remembers. “They had put a
plastic inflatable splint on his arm. As the altitude changed, his
hand went numb, and I had to take the splint off. It took the skin
off his arm, too. It made me sick to my stomach, and the feeling
comes back even now.”

A splint is a simple device used to stabilize bone fractures and
breaks while preventing further injury. It requires something that
maintains its shape in order to hold a broken bone in place and keep
the broken pieces from moving within the limb. The difficulty is that
different bones come in different sizes and shapes.

Around 1971, Dr. Scheinberg experienced his Aha! moment. While
watching TV after 24 hours of surgery, he began to mindlessly bend an
aluminum gum wrapper around his little finger. When the wrapper
became firm and supportive, Scheinberg realized this concept could be
used to create a splint in the same way bending a piece of paper just
right can make a dustpan for sweeping.

In 1976 at the American Academy of Orthopedic Surgeons, Scheinberg
presented his idea for a splint that could be used on almost any
injured part of the body. The following year, he patented a thin
strip of aluminum sandwiched between two layers of closed-cell foam
as the Sam Splint. The mechanics has to do with the physics of curved
surfaces: A flat thin sheet of soft metal is flimsy and weak, but
when curved in cross-section, that same structure becomes amazingly
rigid and strong.

Scheinberg, busy with his orthopedic practice, set the idea aside
until 1984 when his wife, Cherrie, literally chased him around their
house until he agreed to finish what he started. Scheinberg describes
it as the luckiest 10 minutes of nagging in his life. The first new
prototype was created in their kitchen and packaged in an Oreo cookie
wrapper.

Twenty-three years and many millions of splints later, the Sam Splint
has become the standard for hospitals, athletic trainers,
outdoorsmen, paramedics, safety engineers, and militaries around the
world. “We sell almost everywhere on the planet,” Scheinberg says
from his ranch on the Oregon coast. And sales go beyond the planet,
too. NASA has even used the device on the Space Shuttle.

By the way, don’t bother looking for Machine Gun Kelly’s buried
loot at Scheinberg’s former home on Rayner. Sam and his friends
already checked.

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Fast Pellets

The work of two University of Memphis research professors is enough
to have even an orange-blooded University of Tennessee fan cheer for
these Tigers.

About three years ago, Dr. Warren Haggard, professor in the
biomedical engineering department, was at an Academy of Orthopedic
Surgeons meeting. There, he heard of the Orthopedic Trauma Research
Program initiated by the Department of Defense. One item on the
agenda was a grant program offered for research to discover a way to
reduce infections from combat-inflicted wounds. He applied for and
received a grant. Shortly afterward, he and fellow professor Dr. Joel
Bumgardner went to work.

Germs have long been a killer in warfare, but research in recent
years shows further evidence of the critical importance of treating
the silent killer. A 1993 battle in Somalia brought home that need.
“In the <> battle, researchers followed the
progress of the troops,” Haggard says. “They found that about 25
percent of those soldiers’ wounds became infected because of a delay
in treatment. They also found that if a wound became infected, it
added about six weeks to recovery time.”

“If you’re caught in a battle and get wounded by an IED or other
high-energy weapon, you have a very large wound with a lot of tissue
gone,” says Bumgardner. “One problem is that you lose some of your
body’s ability to fight infections. Your skin is gone, which is a
very effective barrier against infections. Your blood and vascular
system is also damaged, so you can’t get your body’s wound-healing
cells to the site to fight infection and initiate the healing
process. This is a very nice site for germs to set up household.”

The idea sounded simple enough: release antiseptic directly at the
wound site. “We started playing around with the chemistry of calcium
sulfate to try to get it to degrade in a quick way,” Haggard says.
The plaster of paris–like compound already had many other medical
uses, but this application would be entirely different. “We wanted
something that could be applied to the wound, would release a
therapeutic agent like an antibiotic, kill the bugs, and quickly
degrade.”

With the help of research associate Kelly Richelsoph and graduate
student Stephanie Jackson, the scientists created pellets about 4 to
5 millimeters in diameter that contained the antibiotic amikacin. Now
in the testing phase, so far so good.

“The military is very interested,” Haggard says. “They have done
pre-clinical studies simulating an injury. They placed bacteria in
the wound, but the bacteria had a special gene that made them
luminescent so the scientists could easily see where the bacteria
were. They surgical-treated and rinsed out all of the wounds like
they normally do. But to some wounds, they added the calcium sulfate
pellets with antibiotic in the wound. Within 24 hours, the pellets
were gone, and at 48 hours, the wounds had 1,000 times fewer bacteria
in comparison to the wounds that were just surgical treated and
washed out.

Battlefields are not the only places where such an application could
save lives, of course. “You can take this approach domestically,”
Haggard says. “In the hospital, we have resistant organisms that
take up residence. We are hoping we can use this approach there, too.”

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MicroDex Robot

What is the best way for an experienced surgeon and a design engineer
to work together on improving surgical technology? Dr. Steve Charles
has an idea: Just have them inhabit the same body.

After graduating in engineering, Charles went to medical school. “I
decided to design medical instruments as well as be a surgeon,” he
remembers. But operations on brain tumors, certain aneurysms,
cervical spine problems, and functional neurosurgery for pain and
seizure disorders require very high dexterity that can challenge even
the best of free-hand surgeons. Worse, many difficult health
situations are classified inoperable because of the extreme precision
requirements and, therefore, the improbability for success.

As a young medical student in 1965, Charles — now a board-certified
ophthalmologist and clinical professor at the University of
Tennessee — saw this dilemma firsthand. Ten years later, he had a
personal stake in addressing it.

“The first thought that hit me in med school was that microsurgery
is absolutely fascinating,” Charles remembers. “But there’s no
reason a human being should be able to move their hands at 20
microns” — a distance of 20 millionth of a meter. “Why would we
be able to move our hands with 20 times greater precision than the
naked eye can see? It hit me that we need a microscope for our hands.”

That thought simmered on the back burner until 1975. Charles was in
Memphis in his first year of practice as an ophthalmologist when a
call came from his mother that his father had a brain tumor. His
father’s parting words were: Steve, you need to take your engineering
skills to neurosurgeons to help people like me.

So Charles invented his own class of robots with a new technology
called “dexterity enhancement.” MicroDex provides a small robotic
mechanism that is attached to a stereotaxic (precision positioning)
framework.

“Gravity disappears, so a heavy drill is no longer heavy,” Charles
says. “Velocity is controlled, and we can set up ‘no fly zones.’
We can confine our work to a certain area. It will give a barrier to
your hand like an invisible teacher holding your hand saying,
‘don’t go there.’ We have the ability to scale motion. You can
set it so your hand moves an inch and the instrument moves half an
inch or an eighth of an inch.”

It’s nothing but smooth motion and flow of force and torque. “It
can’t have gears,” says Charles, who is also founder and chairman of
MicroDexterity Systems, a medical device company building a family of
medical robots, and the Charles Retina Institute. “It can’t have
cable drives; it can’t be heavy. We had to build a system that
allowed it to move incredibly smoothly but could also tell it to stop
immediately. The system must have high-fidelity tactile feedback.”

The technology is awaiting approval, and when approved, will be used
for knee surgery, spine surgery, and neurosurgery, a strange
application for an ophthalmologist, but that engineering background
combined with medical training makes it a natural fit.

“Bryant Gumbel wanted to interview me to do a show on medical
entrepreneurs,” he remembers. “I told him I’m not interested.
It’s about helping people, not being an entrepreneur. I’m a
physician and an engineer, and the charge of both fields is to do
things that help people. I promised my dad that I would do this.”

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Medical Education Research Institute (MERI)

At Medtronic’s Memphis office, a wall of about 70 patents issued to
Dr. Kevin Foley is displayed. “It’s impressive,” says Elizabeth
Ostric, MERI’s executive director. It’s so impressive, that it’s a
little like visiting Graceland and seeing the wall of Elvis’s gold
records.

But perhaps Foley’s greatest invention is not a procedure nor an
instrument but rather a contribution to patient care by creating a
way in which doctors are trained. Continuing education for surgeons,
residents, and students — more than 5,000 per year from around the
world — learn minimally invasive surgical techniques on deceased
human donors at MERI, a 27,000-square-foot medical instructional
facility that provides critical hands-on practice to surgeons in
preparation for giving care to their living patients.

The original idea of MERI came from the military — when Foley came
to Memphis from Walter Reed Army Institute of Research in Silver
Spring, MD, the largest and most diverse biomedical research
laboratory operated by the Department of Defense.

“The military has many dedicated people who donate their lives to the
service of the country,” Ostric explains. “They practice new surgical
techniques and improve current surgical techniques and tools with the
support of these generous anatomic donors. Foley — with support from
Semmes-Murphy Neurologic and Spine Institute, Methodist Le Bonheur
Healthcare, and Baptist Memorial Health Care — brought that
philosophy to Memphis in 1992.”

The classroom resembles an OR for 10 patients, with spaces where a
faculty surgeon — surrounded by several student surgeons and MERI
staff — learns how to perform a new minimally invasive procedure,
such as working with a new knee product or properly inserting spine
implants.

“In the past couple of decades, the pace of medical innovation has
quickened,” Foley says. “The things you learned in med school
don’t remain current as long as they might have in the past. New
techniques have been developed to improve medical care that you may
never have been exposed to while you were learning.”

MERI also provides a means for companies to perform groundbreaking
research that includes surgeon-led new designs for medical devices,
and testing prototypes prior to seeking FDA approval.

“Think of MERI as a school for post-graduate, practical hands-on
training,” Foley says. “A company that has a new procedure or
device might approach MERI and ask to put on a course teaching how to
use the device. We have in Memphis a long history of medical device
development. Many of the innovations are driven by device companies.
It interfaces very nicely with Memphis’s drive to be a real
biotechnology center nationally and internationally.”

MERI, a nonprofit, is the largest hands-on training center of its
kind — anywhere. “We have been approached to franchise the MERI,”
says Foley. “I explained that this is not a business. But we have
helped other institutions follow the model so there are some other
similar teaching centers elsewhere. It’s exciting to develop new
things but it’s more exciting to see them actually help the patient.
It’s very rewarding to teach fellow physicians. If you do something
yourself, you can affect patients. But if you teach a hundred
physicians, you can affect thousands of patients.”

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