|An obstacle course at the University
of Pittsburgh's Human Engineering and Research Laboratories
tests wheelchair stability and the effects of bumps on wheelchair
riders. (Graduate student Erik Wolf is pictured in the chair.)
(Photo by Carl Bower)
HEALTH AND SCIENCE BEAT
Long-Term Wheelchair Use Leads to Stress Injuries
in People With Disabilities
BRUCE TAYLOR SEEMAN
Newhouse News Service
users, confined to their seats with severed spines, limp legs and broken
hips, are encountering a new set of modern maladies.
They are being hurt by the wheelchairs themselves.
Because of medical advances, many disabled people are living longer and
getting around more. The population of wheelchair users outside nursing
homes is climbing sharply, from about 720,000 in 1980 to an estimated
2.2 million today.
But the flip side of longer, more active and independent lives has become
excruciating: torn shoulder muscles, pinched wrist nerves, wrenched backs
and sores on legs and backsides.
"We're getting the consequences of aging," said Lucy Spruill
of Pittsburgh, a 30-year wheelchair user whose ripped rotator cuffs left
her temporarily unable to lift her arms. "This is what's happening
to me instead of the hip replacement that my (able-bodied) friends are
A cadre of doctors and engineers is dissecting the phenomenon, testing
new theories about the human body, the wheelchair and the complex physiology
of hand-to-wheel repetitive motions. Ideas are surfacing to prevent injuries,
which cost millions of dollars and create new barriers to daily freedoms.
"I can hardly go a half a block because of the shape I'm in with
my hand," said Melvin C. Braxton, 59, of Baltimore. A bone protrudes
from the base of his sore left thumb, Braxton said, because he's been
forced to push his Medicare-approved wheelchair at an awkward angle since
he was paralyzed in a 1964 car accident.
More than 400,000 people in manual wheelchairs experience serious secondary
injuries to their shoulders, wrists, backs and other body areas, according
to leading researchers at the University of Pittsburgh.
Increasingly, blame is aimed at a health care system that has not kept
pace with gains made by the disabled rights movement, researchers said.
-- The modern inventory of wheelchairs could fill a new car showroom,
but doctors typically aren't trained to prescribe the right chair for
a particular illness, body type and lifestyle, researchers said.
-- Medicare and private insurance, meanwhile, routinely match patients
to chairs that are less expensive in the short run, but too heavy and
ill-fitting, causing health problems over time.
-- Patients rarely get enough instruction on wheelchair fundamentals --
axle, seat cushion and backrest adjustments, wheel stroke techniques and
Reform has lagged, advocates said, because expectations remain low for
the disabled to thrive in mainstream life -- succeeding at work, raising
families, traveling and participating in community activities.
For many, the disabled rightly deserve a wheelchair with reliable brakes
and a pair of footrests. But the thinking often ends there, said Rory
Cooper, director of the Human Engineering Research Laboratories at Pitt.
"Our society has basically said, `It doesn't matter. If you need
a wheelchair, give up,"' Cooper said.
The wheelchair's plodding evolution tells much about the nation's awkward
relationship with the disabled.
In the 1700s, wheelchairs were heavy and cumbersome, more like hospital
equipment than mobility aids. A century later, the needs of thousands
of Civil War amputees led to lighter wheelchairs, but those veterans were
institutionalized. In another 80 years, soldiers injured in the early
stages of World War II were issued those same Civil War wheelchairs.
Franklin D. Roosevelt, discontented with the clumsy chairs available during
his presidency, preferred a kitchen chair fitted with wheels.
It took the innovations of wheelchair athletes of the 1970s, plus mandates
in the decade-old Americans With Disabilities Act, before wheelchairs
began to change significantly.
Bob Hall, the first wheelchair athlete to complete the Boston Marathon,
recalls pulling apart one of the archaic chairs.
"It had stuff I did not need: armrests, push handles, brakes,"
said Hall, now president of Newhall's Wheels, a Cambridge, Mass., wheelchair
manufacturer. "The stuff that was in the way, I threw out."
Hall later created a chair from scratch. With a lighter, simpler frame
and wheels angled for stability, it was coveted by other riders stuck
in standard, clunky chairs.
"As users, we want to look cool and get there sooner than later,
and feel good about ourselves," Hall said.
Today's wheelchair inventory still includes plenty of the old standard
model, known as the "depot." With a chrome skeleton and vinyl
seat, the 50-pounder has changed little since it was invented in 1932
by a pair of mining engineers.
Next up the hierarchy are lightweight chairs. Weighing between 25 and
40 pounds, the steel or aluminum lightweights offer modest adjustments,
such as movable armrests.
At the top end of the market are ultralights, which may weigh as little
as 15 pounds. A user who can afford one gets a chair with an adjustable
axle, seat, backrest and more.
But the old depot remains a standard in hospital corridors and medical
supply stores. About six in 10 American wheelchair users ride in a depot,
Economics is a big factor. While the better chairs may cost $2,000 or
more, a foldable depot is available for $200 or so.
The low price is attractive to many insurers. But researchers argue that
the inexpensive chairs actually cost more over time because they wear
out in only a year or two. More important, their weight and lack of adjustability
are blamed for injuries.
In one familiar scenario, a chair that's too heavy and badly fitted might
gradually cause rotator cuff damage so severe that shoulder repairs are
needed. Surgery and rehabilitation might cost $100,000.
"That's a lot of wheelchair," said Dr. Michael Boninger, the
Human Engineering and Research Laboratories medical director.
Research has revealed a variety of risks associated with wheelchairs.
At least 50,000 U.S. wheelchair riders require emergency room treatment
each year, according to research. Most are hurt in "tip and fall"
Of those, about 50 die annually, said Dr. Lee Kirby, professor of physical
medicine and rehabilitation at Dalhousie University in Halifax, Nova Scotia.
Most succumb to head injuries.
"It's all too common we see people in a dangerous chair," Kirby
said. "But I also feel it's not only picking the right chair, it's
training people to use the chair in an environment that makes sense. We
don't train them on curbs, or grass or gravel, or sidewalks that have
heaved a little."
More than half of today's wheelchair users suffer chronic injuries from
long-term wheelchair use, Boninger said. Rotator cuff and carpal tunnel
problems are most common, he said.
Such circumstances were rare before medical advances extended the life
expectancies of people with spinal cord injuries and many diseases.
"Before World War II, if you got a spinal injury, you died,"
Boninger said. "It might have taken you a couple of years, but you
probably died of renal failure. In developing countries, you still die.
But this is new, people being in wheelchairs for 30 or 40 years."
The Pitt research lab, housed at the Veterans Administration Pittsburgh
Health Care Center, is widely known for its secondary injuries studies.
In the cinder-block rooms, which hold an eclectic collection of equipment
ranging from soldering guns to blank-faced manikins, researchers have
launched groundbreaking tests of machines and bodies.
To test how wheelchairs hold up in weather, they are placed in a giant
box that gets as hot as 160 degrees and as cold as 40 below zero. The
chairs are run through an obstacle course to measure maneuverability and
perched on rolling drums that simulate bumping over a tree root or sidewalk
crack 800,000 times.
In one test, a chair is rolled up a ramp to measure the angle at which
it will tip over backward. That particular test requires the wheelchair
to be occupied, by either a dummy or a graduate student, Cooper said.
More complex tests are used to check humans who are developing secondary
In one test, a patient's seating is evaluated by a device that uses sensors
to measure pressure on thighs and buttocks. Seating angles and cushions
can be changed to avoid sores.
In another, a patient pushes a stationary wheelchair while computers measure
the complicated mix of muscle forces and body geometry. A sensor on the
wheel computes how hard a patient works each joint. Meanwhile, to record
body mechanics, special cameras follow 22 dime-sized infrared sensors
attached to a patient's arms, legs and torso. On a nearby computer monitor,
the sensors are depicted on a blank background; the wheelchair rider looks
like a constellation in motion.
Researchers can pinpoint many problems through such tests. A patient's
hand stroke may be too short or too forceful. His torso may lean too far
forward, his hand may twist inward, the chair's push rim may be too narrow
or the wheel position may require a backward reach.
Spruill, a patient at the Pittsburgh clinic who has spina bifida, had
to switch to an electric chair because her rotator cuff damage was so
severe. Shoulder pain overtook her gradually as she spent years in a manual
wheelchair that was too heavy and poorly fitted.
"I couldn't concentrate on a TV program, on a book, on my work,"
Spruill said, recalling the discomfort. "I couldn't enjoy fun things
with my friends. There was a time when I realized I hadn't enjoyed a balanced
meal in months. I would just come home and eat something cold or heat
The rotator cuff refers to the four muscles that allow the shoulder to
rotate and provide stability to the arm. Attached to bone by a common
tendon, the structure also helps keep the upper arm bone from sliding
out of place.
Through overuse or improper biomechanics, the rotator cuff may become
inflamed and tear.
"For a pitcher," Boninger said, "it may be career-ending.
For a wheelchair user, it may be the loss of independence."
Carpal tunnel syndrome, meanwhile, is a wrist problem better understood
in recent years because thousands of computer keyboard users have reported
discomfort in their fingers, hands and wrists.
It occurs with overuse and strain. The median nerve, which extends down
the arm, passes through the wrist between bones and ligament. Pressure
increases on the nerve when it becomes inflamed. Results include tingling,
pain and clumsiness.
Such symptoms, whether they appear in the hands or elsewhere, are the
kinds of warnings that terrify disabled people who rely so completely
on their arms.
Christopher Curtis, 42, of Baltimore, a quadriplegic with some use of
his arms and hands, recently fought off a bout of elbow pain. He said
any surgery would "stop my life." Rehabilitation would mean
hiring someone to help him get out of bed and complete other basic tasks.
"Knowing that those (secondary injuries) are out there, any twinge
is like getting caught in the headlights of a car," Curtis said.
"You go, `Oh, no!' When it goes away, you say, `Whew."'
Barbara Ruggles, 48, of Cincinnati, was paralyzed in a 1971 car accident.
Active in wheelchair sports and other activities for years, she developed
the numbness that signals carpal tunnel syndrome.
The pain began in 1984. Surgery on her left wrist came seven years later.
"I controlled it with anti-inflammatory medicine," Ruggles said.
"You just learn to cope. Since I depend on my hands for everyday
living activities, for eating and getting dressed, it was a real big scare.
I think it would have helped to have a lighter chair from the beginning,
or an electric chair."
A better chair would have eased the most exhausting days, the trips to
the zoo or amusement parks, when she sometimes pushed her heavy wheels
Today, further wrist problems have forced Ruggles into an electric chair.
It's a permanent change.
"I really miss the sports activities," she said. "I used
to go on camping vacations, white-water rafting. But I can't do it anymore.
I don't have any strength."
An antidote to secondary injuries will be difficult. The population of
wheelchair users will grow. They will live longer. And there is no swelling
movement to reform insurance reimbursements that match patients with the
Mary Rodgers, chairwoman of the Department of Physical Therapy at the
University of Maryland School of Medicine, said an ongoing study suggests
that exercise can prevent secondary problems.
Exercising with large rubber bands to stretch and grow stronger, study
subjects are showing less strain on muscles and tendons. What's unknown
is whether the regimen will work over time.
"There's a real need for long-term types of studies," Rodgers