An interesting confluence of repetitive stressors
formed the basis of a study of elite youth baseball
players in Japan, published last year in the Journal
of Shoulder and Elbow Surgery. Researchers from To-
hoku University School of Medicine followed 200
boys between ages 9 and 12 at a national tourna-
ment and found a relationship between extensive
video-game play and pain in the elbow and shoul-
der; players who spent three or more hours a day on
video games over the previous year were 5.6 times
as likely to have felt elbow or shoulder discomfort
as were kids who spent less than an hour daily at the
video screen. Gaming has become increasingly pop-
ular in big-league clubhouses, particularly among
starting pitchers, who have several idle days between
their turns on the hill. When Boston Red Sox ace
David Price came down with a case of carpal tun-
nel syndrome last year, some blamed his enthusiasm
for the war-themed video game Fortnite. (Price—
who is midway through a seven-year, $217 million
contract—denied the connection, noting that he’s
been an avid gamer for two decades.)
In all cases of repetitive stress, whatever their
origin, an obvious and elegantly simple preventive
measure is to refrain from overuse. Today, amateur
baseball teams are confining pitchers to strict pitch-
per-game counts, thanks in large part to studies by
Fleisig, Andrews and colleagues. On the website
pitchsmart.org, researchers have compiled a detailed
chart with optimal pitch-count guidelines and rec-
ommended rest periods at various ages from child-
hood through college. For example, an 11-year-old
with one day’s rest between outings should throw
no more than 35 pitches; on three days’ rest, that
maximum nearly doubles, to 65. For major leaguers,
most teams set an informal pitch limit between 100
and 115. Indeed, it’s rare today to see pitchers throw
full nine-inning games, once de rigueur for topflight
starters—in 1974, the year of Tommy John’s surgery,
Hall of Famer Ferguson Jenkins notched the most
complete games, with 29. In 2018, by contrast, seven
hurlers tied for the lead with a grand total of two.
Along with downtime, Fleisig emphasizes proper
form. “You want to optimize your mechanics by using
your whole body and reduce the force and stress on
your arm,” he says. It’s a principle that applies to any
sport or occupation. For us computer jockeys, the
science of ergonomics—designing a workplace for
optimum comfort, injury avoidance and efficiency—
has flourished. Elements of posture, desk layout and
chair and screen alignment come into play, as well as
recommendations on how to grip a mouse (not too
tightly), using keyboard shortcuts, how to hold your
wrist (avoid bending it) and other suggestions. Rest
and exercise are paramount—pry your eyes away
from the screen periodically, and make sure to get
up and take a stroll from time to time.
“Rest, recovery and varying the stress can re-
duce the risk of repetitive stress injury,” advises
Fleisig. “Most importantly, each person should lis-
ten to their body. When fatigued, stop the activ-
ity and rest and recover; when there is pain, seek
a medical evaluation to address the issue before it
becomes serious.” •Lateral epicondylitis, or tennis
elbow: Affects the outer part of
the elbow after repetitive wrist and
arm movements—found not only in
tennis players but also in plumbers,
painters, carpenters and butchers.
Medial epicondylitis, or golfer’s
elbow: Affects the inside of the
lower arm, near the elbow. Frequent
playing of certain sports or
repetitive twisting motions can lead
to this condition.
Raynaud’s disease: Blood vessels
in the extremities constrict when
they’re cold or stressed. One trigger
is work requiring vibration, such as
using a jackhammer.
Radial tunnel syndrome: A dull
ache is felt at the top of the
forearm. Too much pushing or
pulling or overuse of the hand
and wrist can painfully irritate
the nerve.
Rotator cuff syndrome: Damage
to any of the tendons that hold the
shoulder joint in place. Common
in work that involves prolonged
overhead activity.
Tendinosis: Overuse causes
degeneration of collagen—the
main structural protein of the
body’s connective tissues—within
the tendons.
Tendinitis: An inflamed tendon.Thoracic outlet syndrome: Blood
vessels or nerves become trapped
between the collarbone and the
first rib. This malady often afflicts
people who use their upper
extremities to haul heavy weights.
Stenosing tenosynovitis, or trigger
finger: A finger becomes stuck in
the bent position; this condition is
also known as “texting tendinitis.”
Can result from repeated, strong
gripping.
Writer’s cramp: Muscle spasm in
overused hands and arms.