Totally Tae Kwon Do Magazine - Issue 17 - Usadojo

Training Through Knee Injuries
KNEE, noun, (from Dictionary.Com): the
joint of the leg that allows for movement
between the femur and tibia and is
protected by the patella; the central area of
the leg between the thigh and the lower leg.
KNEE, noun, the largest joint in the human
body, capable of millions of load-bearing
actions over the course of a lifetime, and a
critical element in a large variety of
activities including walking, running,
jumping, swimming, and tae kwon do.
KNEE, noun, one of the most injury-prone
joints in the human body, site of common
career-ending damage, almost ridiculously
delicate and sensitive to certain stresses
and strains, subject of millions of medical
visits per year, and a source of unending
arthritic pain and discomfort for many,
including tae kwon do practitioners
Which definition is correct? All of them, of
course. The knee is a wonderful and
terrible mechanism, and appears in the
diagram below. 1
34 - Totally Tae Kwon Do
By Ira Hoffman, WTF 3rd Dan
The wonderful: the average person takes
about 6200 steps per day 2 , although this
number is likely to be much higher for TKD
students and other active people. Average
life expectancy in the United States is
about 77.7 years 3 . Omitting the first year
of life when babies crawl rather than walk,
the average person takes:
(6200 steps/day) x (365 days/year) x (76.7
years)
or more than 173 million steps in their life 4 .
For an active person who lives to age 100,
that total can reach over 300 million steps.
Various studies have shown the maximum
impact - the maximum downward force -
during walking is about 1.2 to 1.3 times a
walker’s body weight 5 . Assuming the
average person weighs 140 pounds (a
mass of about 64 kilos), the total pounding
each knee takes over the course of a
lifetime can exceed 15 billion pounds.
What a marvelous device!
And the not-so-wonderful: On the other
hand, the knee is a hinge joint and is not
as stable as “ball and socket” joints (like
the hip). Because this hinge joint,
“sustains some of the greatest stresses
and … is seriously injured with relative
ease, the knee is … a site of vulnerability.” 6
In 2003, patients made approximately 19.4
million visits to physicians' offices because
of knee problems. It was the most common
reason for visiting an orthopedic surgeon 7 .
The knee is subject to ligament tears,
tendinitis, meniscus injuries and bursitis.
Loose bodies torn off of the interior
structure of the knee can become lodged in
the joint 8 . The kneecap can become
dislodged. And the knee is particularly