"Pes anserinus" describes the connection of three tendons: the
sartorius, gracilis and semitendinosus. These tendons combine
and attach to the knee just below the knee cap. The name means
"foot of the goose" and refers to the shape of these tendons,
which resembles a webbed foot. When the bursa (sac) beneath the
pes anserinus becomes inflamed, it causes a painful condition
called pes anserinus bursitis. This is common, affecting up to
10% of runners. It's more common in women and those who are
obese or have diabetes. People with anserinus bursitis feel
pressure or soreness just below the knee cap, on the inner side
of the leg. The pain tends to be worse during activity
(especially actions with repetitive knee flexing or rising from
a seated position) and also at night. Pes anserinus bursitis is
more common among people who: - Are active in athletics,
especially sports that require quick starts, stops or changes in
direction, like basketball and tennis - Have just started an
exercise program or have recently i