What Might Cause Bunions

Overview

A bunion is a bony lump on the side of your foot, which develops when your big toe starts to angle towards your second toe. The bunion will eventually cause you discomfort and pain. The skin over the lump can become red, blistered or infected. A fluid-filled space called a bursa may also develop under your skin in this area and this can be painful if it becomes inflamed. This is called bursitis. The deformity of your big toe combined with a bunion is sometimes referred to as hallux valgus.

Causes
What causes bunions? This question is often answered by blaming shoes. But in fact, shoes only play a small role in developing bunions. Yes, shoes, especially high heels cause abnormal squeezing of your forefoot. This in turn to help promote a bunion. But if everyone who wore high heels shoes had a bunion, there would be a lot more then the 15% prevalence we see in the general population. As you can see from the flow chart, genetics plays the major role in development of bunion deformities. Genetics determines the way your foot functions. Are you flatfooted? Are your joints flexible or stiff? Do you have a high arch? Do you have tight muscles? These traits are determined by your genetic code. These characteristics then govern how your bones and joints move when you walk. As an example, if your joints are very flexible, this can cause an abnormal amount of instability in your forefoot when you walk. Over time, this abnormal motion will cause the a bunion to develop by allowing your first metatarsal to "drift" towards the mid-line of your body.
SymptomsSigns and symptoms of a bunion include the base of the big toe is swollen and sticks out. The big toe is often bent towards the other toes, and sometimes the second toe is pushed to overlap the third toe. Skin around the big toe joint is red and sore. Thickened skin at the base of the big toe. Pain in the big toe or foot. Wearing shoes is painful. Pain or difficulty when walking.

Diagnosis
Orthopaedic surgeons diagnose bunions on the basis of physical examination and weight bearing x-rays. Two angles are assessed, the intermetatarsal angle, that is between the first and second metatarsals (the bones that lead up to the base of the toes). If this angle exceeds 9? (the angle found in the healthy foot) it is abnormal and referred to as metatarsus primus varus. the hallux valgus angle, that is, the angle of the big toe as it drifts toward the small toe. An angle that exceeds 15? is considered to be a sign of pathology.

Non Surgical Treatment
Bunion pain can be successfully managed in the vast majority of cases by switching to shoes that fit properly and don't compress the toes. Your orthopaedic surgeon can give you more information about proper shoe fit and the types of shoes that would be best for you. Follow these general points of shoe fit. Do not select shoes by the size marked inside the shoe. Sizes vary among shoe brands and styles. Judge the shoe by how it fits on your foot. Select a shoe that conforms as nearly as possible to the shape of your foot. Have your feet measured regularly. The size of your feet change as you grow older. Have both feet measured. Most people have one foot larger than the other. Fit to the largest foot. Fit at the end of the day when your feet are the largest. Stand during the fitting process and check that there is adequate space (3/8" to 1/2") for your longest toe at the end of each shoe. Make sure the ball of your foot fits well into the widest part (ball pocket) of the shoe. Do not purchase shoes that feel too tight, expecting them to "stretch" to fit. Your heel should fit comfortably in the shoe with a minimum amount of slippage. Walk in the shoe to make sure it fits and feels right. (Fashionable shoes can be comfortable.) Some shoes can be modified by stretching the areas that put pressure on your toes. Splints to reposition the big toe and orthotics (special shoe inserts shaped to your feet) also may relieve pain. For bunions caused by arthritis, medications can be prescribed to reduce pain and swelling.


Surgical Treatment
In cases where joint pain and deformity are severe, joint replacement surgery may be recommended. This may particularly be recommended when arthritis is present in the joint. Surgery may be carried out under a local, regional or general anaesthetic. Most cases are performed as a day stay procedure. However, an overnight stay in hospital may be required if the surgery is more extensive. The type of surgery to be performed, the type of anaesthetic to be used and the expected hospital stay should be discussed with your surgeon prior to surgery.