Bunion

A bunion is a bumpy outgrowth of the joint between the big toe and the foot (the first metatarsophalangeal joint).

A bunion is almost always accompanied by deviation of the big toe toward the second toe. Bunions are common in older people. Treatment often helps control symptoms, or bunions can be removed surgically.

See the figure What Is a Bunion?

A bunion usually develops over many years. However, as a bunion becomes more noticeable and the big toe deviates, troublesome changes may occur in and around the joint. Calluses may form around the joint. Osteoarthritis may develop. Pointy protrusions (spurs) may form at the ends of the two bones that come together in the joint. Sacs around the joint (bursa) can become inflamed. Wearing proper footwear can reduce symptoms. Surgical removal of a bunion is sometimes necessary.

Causes

Heredity may play a role, because bunions seem to run in families. Ill-fitting footwear may also contribute to the development of bunions. Wearing footwear with a narrow toe box (the portion of the shoe where the toes fit) puts pressure on the base of the big toe, where the first metatarsophalangeal joint is located.

Symptoms and Diagnosis

For many people, bunions prove to be nothing more than cosmetically unappealing. Any callus that forms, however, may cause discomfort. Because footwear puts increasing pressure on the joint as the prominence grows, the bunion often becomes painful. Pain may worsen if osteoarthritis develops. Pain may also worsen if spurs form or if sacs (bursas) form and become inflamed. Walking may become difficult because of pain and deviation of the big toe, which may push over or under the other toes.

A doctor diagnoses a bunion during a physical examination. An x-ray can show changes in the bone, including osteoarthritis and bumpy outgrowth of bone, but in most cases, an x-ray is done only if surgery is being considered.

Treatment and Outlook

Wearing proper footwear can reduce symptoms. People with a bunion benefit from wearing shoes with more room and flexibility in the toe box, so that pressure on the first metatarsophalangeal joint is lessened. The doctor may recommend an insert (orthotic) for the shoe to reduce friction and pressure. Wearing footwear that fits properly may help reduce pain and inflammation. The bunion may even shrink, although it will not disappear completely.

Surgery is sometimes performed as a last resort when pain cannot be relieved by adjusting the shoe. Surgery consists of shaving away the bumpy areas of bone that have formed at the ends of the two bones that join in the metatarsophalangeal joint. Surgery can also remove any spurs that have formed. During surgery, a wire or rod may be inserted temporarily into the big toe, so that the toe can be realigned to its normal position. After surgery, bunions rarely recur.