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Overview

A bunion is a deformity of the metatarsophalangeal (MTP) joint at the base of the big toe. A bunion develops when the first metatarsal bone of the foot turns outward and the big toe points inward (toward the other toes), causing the joint to jut out. A bunion is most likely to develop when susceptible feet are repeatedly squeezed into narrow, pointed-toe footwear. The big toe pushes against the other toes, sometimes diving over or under them. As a result, the base of the big toe ? the metatarsophalangeal (MTP) joint ? juts or angles out from the foot.

Causes
Bunions are a common problem that can cause foot pain and difficulty wearing shoes. Bunions occur in about 30% of the population of most Western countries. They are seen most commonly in women and become more common as people get older. Patients with bunions generally have one of two problems that can cause pain. As the big toe becomes more and more angled (pointing toward the other toes), the base of the toe becomes more and more prominent, forming the bunion. The bunion forms in part because of the new angle of the toe, and in part due to inflammation over the bunion surface. As the inflammation worsens, people can experience pain with shoe wear and walking. The big toe may eventually come to lie over, or more commonly under, the second toe. This may cause further irritation while wearing shoes and more pain. The second toe of patients who have bunions commonly forms a hammer toe.
SymptomsA bunion, also called a hallux valgus, is a bony prominence on the inside of the big toe, caused by a misalignment of the joint. The overlying skin maybe swollen, red and tender. Bunions are often painful and can limit what shoes you can wear.

Diagnosis
Although bunions are usually obvious from the pain and unusual shape of the toe, further investigation is often advisable. Your doctor will usually send you for X-rays to determine the extent of the deformity. Blood tests may be advised to see if some type of arthritis could be causing the pain. Based on this evaluation, your doctor can determine whether you need orthopaedic shoes, medication, surgery or other treatment.

Non Surgical Treatment
When the deformity is mild, treatment is usually not necessary. However, changing shoes to ones that have little or no heel, and are wider in the toe area (toe box) will be more comfortable and may help to prevent worsening of the bunion deformity. If the bunion starts to become painful, other measures may help. Bunions can cause pain in several different areas. The medial eminence may be painful, the entire first toe joint may hurt, or there may be pain underneath some or all of the forefoot (the ball of the foot). Pain over the medial eminence is the most common problem that affects bunion patients. A ?toe spacer? can be placed between the first and second toes and can provide some pain relief as it straightens out the bunion slightly. Pads placed over the medial eminence itself are hard to keep in place and rarely help to relieve pain. Pain underneath the first toe or lesser toes can be relieved by pads placed in the shoes in precise areas. The pads help to take pressure off the prominent areas on the bottom of the foot. Generalized measures to relieve bunion pain, such as physical therapy or foot stretching exercises, have not been shown to be helpful. Orthotics are often prescribed, but are also rarely helpful in relieving pain over the bunion, but may help with pain felt under the ball of the foot.


Surgical Treatment
Bunion surgery is most often performed as an out-patient, this means you go home that same day. It will likely be done at a hospital or out-patient (ambulatory) surgery center. The anesthetic choices with bunion surgery are local with sedation, spinal or general anesthesia. You wouldn?t expect that a small bunion would be treated exactly the same as a large one. Over the years, surgeons have developed dozens of methods to surgically correct bunions. But don?t worry because only a handful of methods are used today. With most bunion surgeries today, the procedure involves a combination of soft-tissue rebalancing of ligaments and tendons as well as bone work to re-align the foot structure. You may have heard people say they had their ?bunion shaved.? In most cases, the surgery often involves much more than simply shaving the bunion. The shaving part of the procedure is called an ?exostectomy? and often performed in conjunction with other methods.

Prevention
Wear insoles and well-fitting shoes to help slow down the progression of bunions and alleviate discomfort. Cushioning can also help alleviate discomfort. Consider wearing shoes with a wide toe box so they don't crowd your toes. Children can also develop bunions and should wear properly fitting shoes as their feet are still developing.