Hallux valgus

What is a bunion?

When your big toe is angled towards the second toe, the deformity is called a bunion (hallux valgus). This causes a bony bump (fluid-filled sac) on the side at the base of the big toe. In addition there is often thickening of the skin and tissues next to the affected joint. The thickened skin and tissues may become inflamed, swollen and painful.

Sometimes a fluid-filled sac (bursa) develops over the joint.

Foot diagram showing bunion

The underlying cause of bunions is a deformity of the joint at the base of the big toe. The deformity is called hallux valgus. In this deformity the joint develops a prominent sideways angle. Due to this deformity the foot bones and bones of the big toe are pushed towards the smaller toes.

The skin over the angled joint then tends to rub on the inside of shoes. This may cause thickening and inflammation of the overlying skin and tissues next to the bunion affected joint.

Are bunions hereditary?

In most cases it is not clear why people develop bunions. There may be some hereditary (genetic) tendency to have a weakness of this joint. In some cases it is associated with a joint problem such as osteoarthritis or la polyarthrite rhumatoïde.

However, whatever the underlying cause of bunions, wearing tight or badly fitting shoes tends to make the problem worse. Wearing such shoes puts extra pressure on the big toe joint and causes friction on the overlying skin.

Bunion pain is very common, often resulting in difficulty walking or wearing shoes. Other bunion complications can include:

• Inflammation and swelling at the base of the toe. This sometimes becomes infected.

• The foot may become so wide that it can be difficult to find wide enough shoes.

• You may develop arthritis in the big toe.

• The second toe can become deformed. In severe cases, the big toe can push your second toe up and out of place.

Wearing shoes that are comfortable

Wearing good footwear does not cure bunions but may reduce pain and discomfort. Ideally, get footwear advice from a person qualified to diagnose and treat foot disorders (podiatrist - previously called a chiropodist) and choose shoes accordingly.

Advice may include:

• Wear shoes, trainers or slippers that fit well and have room for your toes.

• Don't wear high-heeled, pointed or tight shoes that put pressure on your bunions.

• You might find that shoes with laces or straps are best, as they can be adjusted to the width of your foot.

• Bunion pads or toe spacers may help, as may ice packs.

• Devices which help to straighten the toe (orthoses) may be recommended. However, there is no evidence they improve the underlying condition or stop it getting worse. They may help reduce the pain, at least for a while.

Medication for bunions

Painkillers such as paracétamol ou ibuprofène are a non-surgical treatment option that may help ease any pain. A course of antibiotiques may be needed if the skin and tissues over the deformity become infected.

Bunion surgery

An operation may be advised if a change of footwear does not ease symptoms of your bunions. The aim of the bunion surgery is to straighten the joint as much as possible and relieve pain. It is not usually done just to improve appearance of the bunion. It can be done using a local or a general anaesthetic and you are usually out of hospital the same day.

There are many different types of operation which are used to treat bunions. These range from operations to trim parts of the joint, to a total artificial replacement of the big toe joint (similar to a knee or a hip replacement). A common surgical procedure used is called a scarf osteotomy (osteotomy means a cut in the bone). In some cases the joint may be fused together so it no longer moves (arthrodesis). The exact operation chosen by the specialist depends on:

• How severe the bunion is, and how deformed your foot.

• The shape of your foot.

• If you have wear and tear (l'arthrose) in the joint.

• Their personal experience and expertise.

An operation is usually successful at easing symptoms of bunions but not in all cases. It is not always possible to relieve the pain completely or make the toe perfectly straight. Your specialist will be able to advise on the pros and cons of surgery and on the success rate of the chosen operation. Complications of the operation can include:

• Continued pain.

• Infection.

• The bunion returning (recurrence).

• General risks of operations and anaesthetics.

You may need to wear a special shoe for six weeks after the bunion operation. Your hospital will give you specific information and advice. You may be given a leaflet with information about the procedures at your hospital and with advice for after the operation. See the Royal National Orthopaedic Hospital leaflet, in references below, for an example and further details.