The primary purpose of shoes is to protect your feet and prevent injury. But in order to do so, they must fit well. Poorly fitted shoes--shoes that are too narrow, too short or too large--can cause discomfort, injury and even permanent deformity.

Understanding the components of proper fit can help you make sensible shoe purchases for yourself and your family. This brochure describes the parts of a shoe and how they can affect fit. It also discusses special considerations related to children's, men's, women's, work and athletic shoes, and provides recommendations on footwear selection.

Although style is often a key consideration in choosing a pair of shoes, the most important quality to look for in shoes--from a practical standpoint--is durable construction that will protect your feet and keep them comfortable. In selecting shoes, keep this basic principle of good fit in mind: Your shoes should conform to the shape of your feet; your feet should never be forced to conform to the shape of a pair of shoes. Soreness, blisters, callouses, and, with time, permanent disfigurements can be caused by habitually crowding your feet into shoes that don't fit well.

Anatomy of a Shoe

A shoe is composed of different parts. Understanding the basics of shoe construction can help you choose intelligently from among the thousands of available styles.

The toe box is the tip of the shoe that provides space for the toes. The toe box may be rounded or pointed and will determine the amount of space provided for the toes.

The vamp is the upper middle part of the shoe where the laces are commonly placed. Sometimes Velcro is used instead of laces.

The sole consists of an insole and an outsole. The insole is inside the shoe; the outsole contacts the ground. The softer the sole, the greater the shoe's ability to absorb shock.

The heel is the bottom part of the rear of the shoe that provides elevation. The higher the heel, the greater the pressure on the front of the foot.

The last is the part of the shoe that curves in slightly near the arch of the foot to conform to the average foot shape. This curve enables you to tell the right shoe from the left. On occasion. an orthopaedic surgeon may prescribe a child's shoe that has a straight or reverse last.

The material from which the shoe is made can affect fit and comfort. Softer materials decrease the amount of pressure the shoe places on the foot. Stiff materials can cause blisters. A counter may be used to stiffen the material around the heel and give support to the foot.

Recommendations for Footwear

• Because your feet may vary in size, ask the salesperson to measure the length and width of each of your feet.
• Your feet expand when bearing weight, so stand while your feet are being measured.
• Because swelling during the course of the day can enlarge your feet, have your feet measured at the end of the day.
• The shoes you buy should be fitted to your longer and wider foot. Although the toe box should be spacious, too much space can cause the feet to slide around in the shoes, possibly causing blisters or abrasions.
• Shoes should be fitted carefully to your heel as well as your toes. Check to make sure your heel does not slip out of the back of the shoe.
• Walk around in the shoes to make sure they fit well and feel comfortable.

• Don't select a shoe by size alone. A size 10 in one brand or style may be smaller or larger than the same size in another brand or style. Buy the shoe that fits well.
• Select a shoe that conforms as closely as possible to the shape of your foot.
• Have your feet measured regularly. Their size may change as you grow older.
• If the shoes feel too tight. don't buy them. There is no such thing as a "break-in period." With time, a foot may push or stretch a shoe to fit. But this can cause foot pain and damage.
• If one of your feet is considerably larger than the other, an insole can be added to the shoe on the smaller foot.
• Fashionable shoes can be comfortable, too.

Children's Shoes

Children don't need shoes until they begin walking, usually at around 12 to 15 months of age. Until then, socks or booties are enough to protect a crawling infant's feet and keep them warm. When your child does begin standing and walking, however, shoes provide an excellent form of protection from injury. After your child begins wearing shoes, there is nothing wrong with letting him or her go barefoot indoors.

A good time to buy your child's first pair of shoes is when he or she starts standing and walking. Shoe stores that specialize in children's shoes are likely to offer the widest range of sizes and styles, and will usually take more time to make sure a pair of shoes fits properly.

Never try to force your child's feet to fit a pair of shoes.

A soft, pliable shoe with plenty of room, such as a sneaker, is the ideal shoe for children of all ages. The toe box should provide enough space for growth, and should be wide enough to allow the toes to wiggle. (A finger's breadth of extra length will usually allow for about three to six months' worth of growth, though this can vary depending on your child's age and rate of growth.)

If your child frequently removes his or her shoes, those shoes may be uncomfortable. Check your child's feet periodically for signs of too-tight shoes, such as redness, callouses or blisters. And have your child's feet measured periodically at the shoe store to determine whether his or her feet have grown enough to warrant a larger pair of shoes.

Remember that the primary purpose of shoes is to prevent injury. Shoes seldom correct children's foot deformities or change a foot's growth pattern. Casting, bracing or surgery are often needed if a serious deformity is present. If you notice a problem, have your child examined by an orthopaedic surgeon.

Because high-top shoes tie above the ankle, they are recommended for younger children who may have trouble keeping their shoes on. Contrary to common belief, however, high-top shoes offer no advantages in terms of foot or ankle support over their low-cut counterparts.

Men's Shoes

Most men's shoes conform to the shape of the feet and have a roomy toe box with sufficient horizontal and vertical space and a low heel (usually about half an inch high). Soles made of hard materials such as leather or soft materials such as crepe can both be worn, but softer soles tend to be more comfortable. If you stand for extended periods of time, shoes with soft, pliable soles will protect your feet and help keep them comfortable.

Work Shoes

Work shoes are also available with varying characteristics, depending on the wearer's occupation. Boots made of thick leather with steel toe boxes can be worn to protect the feet from injury. Boots with varying degrees of traction also are available.

Women's Shoes

Low-heeled shoes (one inch or lower) with a wide toe box are the ideal choice for women. An ample toe box that can accommodate the front part of the foot is as important as the heel in determining fit.

High-heeled, pointed-toe shoes can cause numerous orthopaedic problems, leading to discomfort or injury to the toes, ankles, knees, calves and back. Most high heeled-shoes have a pointed, narrow toe box that crowds the toes and forces them into an unnatural triangular shape. These shoes distribute the body's weight unevenly, placing excess stress on the ball of the foot and on the forefoot. This uneven distribution of weight, coupled with the narrow toe box characteristic of most high heels, can lead to discomfort, painful bunions, hammertoes. and other deformities.

The height of the heel makes a dramatic difference in the pressure that occurs on the bottom of the foot. As heel height increases, the pressure under the ball of the foot may double, placing greater pressure on the forefoot as it is forced into the pointed toe box.

Even low-heeled shoes can cause problems if they don't fit well. Years of wearing too-small shoes can lead to permanent deformities.

Athletic Shoes

The purpose of athletic shoes is to protect the feet from the specific stresses encountered in a given sport and to give the player more traction. A jogging shoe will be designed differently from an aerobics shoe, for example. The differences in design and variations in material, weight, lacing characteristics and other factors among athletic shoes are meant to protect the areas of the feet that encounter the most stress.

The key ingredient in a well-fitted athletic shoe is comfort. A good fit will reduce blisters and other skin irritations.

Your orthopaedist is a medical doctor with extensive training in the diagnosis, and nonsurgical and surgical treatment of the musculoskeletal system, including bones, joints, ligaments, tendons, muscles and nerves.