What do patients want from their footwear?

Patients may subconsciously use a list of preferential features which may include:

Before beginning to consider the suitability of the footwear presented by the patient we need to establish the type of footwear normally worn by the patient for the large part of the day and identify why they chose that particular style and material. It is also advisable to identify whether they have had any bad footwear experiences. For example have they been persuaded to buy ‘sensible’ footwear only to find that it was expensive and did not improve their foot comfort or their foot health? The purpose for which the footwear is to be used is significant and we should consider whether it is essentially designed to be smart or casual, for work or for a special occasions, regular use or a specific activity.

It is also useful to determine how a patient evaluates the fit of a shoe. They would probably consider a well-fitting shoe to be one which:

The patient’s perspective may be summarised in the word ‘comfort’. Comfort is a term which relates to a lack of discomfort or pain and is directly related to sensitivity levels. It seems that in comparison with the hand, the foot has much lower sensitivity. Table 9.1 shows the differences in two-point discrimination at specific distances on sites on the hand and foot when monofilaments are applied (Goonetilleke & Luximon 2001).

Table 9.1 Sensitivity to Semmes–Weinstein monofilaments and two-point discrimination at points in the hand and foot

Comfort may mean different things to different people. Is it the right feel? The absence of discomfort or pain? When patients like a particular footwear style and want to wear a favourite pair of shoes they can block the pain sensation. Feet and shoes are different shapes and when we put shoes onto our feet we are generally trying to fit an irregular shaped object into a more regularly shaped piece of footwear. However, if we try to replicate the actual individual foot shape into a shoe this will also give rise to problems as the foot undergoes changes in shape on weightbearing, with temperature change, impact, oedema and so on. For a shoe to fit, it ought to allow a certain ‘feel’ against the foot so that the wearer knows they have a shoe on their foot, but it should not cause any discomfort, pain or trauma. Neither should it require the foot to do any additional work in the form of gripping to make the shoe stay on the foot. The shoe should be secure at locations on the foot where deformations during gait will not be significantly large. Such positions will depend on shoe design and include: the grip around the heel, waist-girth, and the height of the shoe matching that at the midfoot. Forward movement of the foot should be restricted by a secure fastening across the instep.

Vamp

The vamp is the front section of the upper of the shoe. It can be made of one or more pieces of material. Sometimes several pieces of material are joined together to form a pattern. The seams and decoration can sometimes irritate the foot, especially bony prominences. In therapeutic footwear the vamp will usually be made of a single piece of leather with no seams. External decoration may be added including decorative aprons or stitching details but there will be only one continuous piece of material against the foot. In therapeutic footwear, the vamp is a common site for added depth, width or girth.

Toe puff (stiffener)

The toe puff is a stiffener between the vamp and the lining. It prevents the vamp collapsing and lifts it over the toes. Retail footwear often contains toe puffs which are extended proximally to cover part, or all, of the dorsal surface of the toes. Such toe puffs may exert pressure on the dorsal surface of clawed or hammered toes. Some footwear is made with toe puffs with additional strength, sometimes out of metal to give added strength and protection (e.g. industrial boots).

Tongue

The tongue is usually cut as an integral part of the vamp. It may or may not be padded. It is usually attached to the vamp only at its base, but it may also be made in ‘bellows’ form. In this form, the tongue material is part of the vamp, but it contains additional wings that are stitched to the quarters in a modified Gibson (Derby) construction (Fig. 9.1). This design allows for variable volume of the foot and so is useful for patients with foot and ankle oedema. A well-padded tongue is often important in patients with tarsometatarsal arthritis to reduce pressure over bony prominences.

Figure 9.1 The parts of the shoe showing the components of a Gibson (Derby) style using a cemented (stuck-on) construction.

Quarters

The quarters are preferably cut in one single piece of leather and contain a dart to meet the required shape at the back of the heel. More commonly, quarters are cut in two separate pieces which are sewn together at the centre back. It is important to avoid seams on the posterior aspect of the heel to prevent irritation of the soft tissues. The facings are also included as part of the quarters. In therapeutic footwear, quarters can be made with variable height or width dimensions to accommodate deformity such as a valgus heel or bony prominences around the ankle.

Heel counters

The heel counters are stiffeners which are included between the quarter and the lining at the back of the shoe. They help maintain the shape of the heel and prevent it from creasing down as the shoe is taken on and off and as the foot moves up and down during gait.

Heel counters may be extended medially, laterally, and proximally upwards from the ankles in boots. Heel counters provide stability and offer some control to the rear part of the foot during heel strike. Counters may also be made of extra strong material for additional reinforcement. Medial reinforcement is useful in pronatory syndromes and mid-foot Charcot neuro-arthropathy. Proximal reinforcement is used in cases of ankle weakness or deformity.

Lining

Linings may be made of a variety of materials, including nylon, fleece and leather. They should reflect the shape of the main parts of the shoe (the vamp and the quarters) but each segment should be seam-free.

Facings

These are the parts of the shoe which form the meeting point of the fastenings. They are part of the quarters. They contain the means of fastening the shoe. In a correctly fitting shoe they should not be under stress or strain.

Fastenings

A variety of fastening systems are used in footwear. The most common are lace stays and eyelets. These may take several forms and contain the laces where these are the means of fastening the shoe. An advantage of laces is that the pressure of the fastening is evenly spread over a wide area avoiding irritation to the soft tissues. Velcro fastenings are a valuable alternative method of fastening for patients who have difficulty with hand mobility or with bending to reach their feet. Velcro straps may be fastened via D-rings or via eyelets contained within the facing. Buckles can be useful fastenings as long as they are functional and not purely decorative. They usually lack the strength of lacing systems and are often less effective over time.

Topline

The topline is the part of the shoe which borders the foot. It should be seam-free and preferably padded to minimize irritation to the retrocalcaneal area or infra-malleolar area.

Throat

The throat of the shoe is formed where seams join the vamp to the quarter. Its position will depend on the style of the shoe. A lower throat line where the vamp is shorter and the quarter longer will give a wider opening allowing easier foot placement into the shoe.

Innersole

The insole is the base of the inner aspect of the shoe. It may be covered by an inlay which contacts the plantar surface of the foot. (Note that what podiatrists understand by ‘insole’ is usually what shoe manufacturers refer to as ‘inlay’.)

Outersole

This is the undersurface of the shoe which makes contact with the ground. It can be made of a variety of materials and textures. The texture determines the level of grip the shoe has on the walking surface.

Shank

Traditional shoe manufacturing methods include the use of a shank. This is a piece of metal that reinforces the waist of the shoe, maintains the relationship between the pitch of the heel and the forefoot and stops the shoe collapsing in the mid-foot. More modern constructions (e.g. Strobel) use resilient soling materials and do not use shanks.

Heel

This is the part of the shoe directly underneath the heel of the foot. The part of the heel nearest the ground which can be repaired is called the top-piece. The heel is usually pitched to a certain height, which is directly related to the toe spring or raised area under the toe part of the shoe.

Toe spring

This is the elevation of the front part of the shoe when the shoe is standing correctly on its treadline (which corresponds with the metatarsophalangeal joints). Toe spring facilitates walking action and compensates for any stiffness in the footwear (see Fig. 9.2).

Figure 9.2 The last – the model on which the shoe is made.

Last measurements and sizing

The length of the last will equate with the finished length of the shoe that is made on it. The foot width and girth measurements are taken at several points. The widest point on the last will equate with the width of the foot at the metatarsophalangeal joints. The width from medial to lateral across the plantar surface of the heel directly beneath the malleoli will also be transferred to the measurement at the corresponding point on the last. Girth measurements are taken at a minimum of five points on the foot to correspond with last dimensions. These points include the circumference of the foot at the metatarsophalangeal joints, the circumference of the foot immediately behind the metatarsal heads (known as the waist measurement), and the circumference of the foot at the instep – in the position of the cuneiform bones. Girth measurements will also be taken from the back of the heel at the plantar/retrocalcaneal border to the dorsal surface of the ankle joint and from the same point at the back of the heel to the point at which the instep girth was taken. These measurements are known as the short and long heel measurements, respectively (see Fig. 9.6B).

Figure 9.6 A The difference between width and girth: the boxes have the same girth measurement (8 units), but the top one has a width of 2 units and the lower one a width of 3 units. B Points at which measurements should be taken to ensure adequate shoe fit: 1 and 3 – joint girth, 2 – foot length, 4 – instep girth, 5 – long heel measurement, 6 – short heel measurement. Measurements 7 and 8 are required for boots: 7 is the boot height and 8 the leg circumference.

The recede

This is the part of the last which projects beyond the tip of the toes forming the contour of the front of the shoe. A tapering recede such as in pointed toe shoes increases the overall length of the shoe. In a poorly designed last the recede may encroach on the toes increasing pressure on the tips of the toes.

Treadline

This line corresponds with the position of the metatarsophalangeal joints and is the point at which the shoe will be designed to flex.

Toe spring

This describes the elevation of the under-surface of the last from the treadline forwards to the toes. It gives a slight rocker effect to the shoe. The amount of toe spring built into the last depends on shoe style, shoe construction method and sole thickness and heel height. Toe spring is designed to make walking in shoes easier. It compensates for the stiffness of the footwear and assists propulsion during gait. The more rigid the soling material the higher the elevation of the toe spring. The higher the heel height the lower the toe spring required.

The flare

This describes the curve or contour of the longitudinal bisection of the last. A last may be inflared, outflared or neutral. In order to describe the flare, a line which longitudinally bisects the heel of the last is carried forwards to the front of the last. The last is said to be inflared when the medial portion of the last across the treadline area is wider than that on the lateral side. The last is said to be outflared when the portion on the lateral side of the treadline is greater than that on the medial. When both sides are of equal width the last is said to have a neutral flare (Fig. 9.3).

Figure 9.3 The flare of the last. The shoe will reflect this finished shape.

For reasons of cosmesis most lasts (and therefore most shoes) are inflared. Some orthopaedic shoes and trainers are of neutral flare. Few shoes are made with an outflare – on rare occasions shoes are made with an outflare to correct in-toeing in children.

What to advise patients about footwear

The first and probably most evident feature is that footwear should fit the feet they are intended for. The length of the shoe should accommodate the longest part of the foot always remembering that digital formulae are not standard and that in some patients one or more of the lesser toes may be longer than the hallux. Length should then be subdivided into the length from the heel to the first metatarsophalangeal joint and the length from the first metatarsophalangeal joint to the toes (Fig. 9.4).

Figure 9.4 The length of the foot; heel to ball measurement.

All feet are different and even if the overall shoe length is correct the treadline of the shoe may not correspond with the metatarsophalangeal joints. This will result in the foot trying to flex at a point where the shoe is designed to limit flexion. If the treadline of the shoe is too far proximal for foot flexion the shoe will acquire additional toe spring from the foot flexion point and the vamp will crease excessively. If it is too far distal the toe spring of the shoe will be depressed by the foot and lead to cramping of the toes. The heel to ball measurements vary amongst manufacturers and it is often worthwhile trying various shoes to ensure that the heel to ball length is adequate.

Shoe width increases incrementally with length and patients with wide feet often choose shoes that are too long for them to obtain adequate width. This also means that the metatarsophalangeal joints will be positioned proximal to the shoe treadline and shoe flexion will not correspond to foot flexion and the shoe will acquire additional toe spring and the vamp will crease. If the shoe contains a shank, the shank may break through the outersole. This is because the relationship between the heel height and the treadline has been changed as the foot requires the shoe to flex in a more proximal position than it was designed to do (Fig. 9.5).

Figure 9.5 A A fashion boot which has acquired additional toe spring due to the foot flexion point being more proximal than the shoe treadline. B The shank has broken through the outersole of this shoe as a result of foot flexion taking place at a point proximal to the treadline of the shoe. The resultant relationship between the heel height and the treadline has been altered by foot function.

The shoe should be of correct width and girth at the metatarsal heads and of correct girth at the instep. Several other girth measurements need to be matched if the shoe is to fit properly (Fig. 9.6). The long heel measurement is perhaps one of the most important in obtaining a good fit and it dictates the positioning of the instep fastening. It is also necessary to remember that the shoe needs to change shape with the foot in gait. The time of the day when taking measurements is also important since normal daytime changes result in a 3% increase in foot volume (Janisse et al 1995) and vigorous exercise can cause an increase in foot volume by 8% (Merriman & Tollafield 1997). The shoe should be large enough to allow for changes in dimension as the day progresses and should also allow for changes in volume required by variation in hosiery, activity, or to accommodate dressings/padding where needed. If the patient needs to wear orthoses, the shoe needs to be able to accommodate them. The shoe should be of adequate width and depth and there should be no localised tight spots. The heel of the shoe should be broad based for stability on heel contact. There should be a functional fastening to hold the foot back in the shoe and to prevent impaction of the toes against the front of the shoe. The topline of the shoe should fit snugly and should not gape. It should not irritate the malleoli or Achilles tendon.