A bunion is a “bump” on the joint at the base of the big toe—the
metatarsophalangeal (MTP) joint—that forms when the bone or tissue at
the big toe joint moves out of place. The toe is forced to bend toward
the others, causing an often painful lump of bone on the foot. Because
this joint carries a lot of the body's weight while walking, bunions can
cause extreme pain if left untreated. The MTP
joint itself may become stiff and sore, making even the wearing of
shoes difficult or impossible. A bunion—from the Latin "bunio," meaning
enlargement—can also occur on the outside of the foot along the little
toe, where it is called a "bunionette" or "tailor's bunion".
form when the normal balance of forces that is exerted on the joints
and tendons of the foot becomes disrupted. This disruption can lead to
instability in the joint and cause the deformity. Bunions are brought
about by years of abnormal motion and pressure over the MTP joint. They
are, therefore, a symptom of faulty foot development and are usually
caused by the way we walk and our inherited foot type or our shoes.
Although bunions tend to run in families, it is the foot type that is
passed down—not the bunion. Parents who suffer from poor foot mechanics
can pass their problematic foot type on to their children, who in turn
are prone to developing bunions. The abnormal functioning caused by this
faulty foot development can lead to pressure being exerted on and
within the foot, often resulting in bone and joint deformities such as
bunions and hammertoes.
Other causes of bunions are foot injuries,
neuromuscular disorders, or congenital deformities. People who suffer
from flat feet or low arches are also prone to developing these
problems, as are arthritic patients and those with inflammatory joint
disease. Occupations that place undue stress on the feet are also a
factor; ballet dancers, for instance, often develop the condition.
Wearing shoes that are too tight or cause the toes to be squeezed
together is also a common factor, one that explains the high prevalence
of the disorder among women.
The symptoms of a bunion include the following:
Development of a firm bump on the outside edge of the foot, at the base of the big toe
Redness, swelling, or pain at or near the MTP joint
Corns or other irritations caused by the overlap of the first and second toes
Restricted or painful motion of the big toe