Shoe serves a variety of functional and cosmetic purposes. For the individual with an orthopedic disorder, footwear can be selected to minimize pressure on sensitive, deformed structures. Shoes can be modified to redistribute weight toward pain-free areas to improve the comfort and function of the foot, limb, and trunk.
The shoe is also is the foundation of an orthosis and needs to be correctly fitted and modified.
Parts of the Shoe
The major components of a shoe are the sole, heel, upper, and linings and reinforcement
In a well- constructed orthopedic shoe, there are two soles. the outer sole and the inner sole. The outer sole, which contacts the floor, should be made of leather.
The inner sole is preferably made of leather, lies under the foot. Below the inner sole is a space occupied by a compressible filler which separates the inner from the outer sole. Above the inner sole is stitched a welt, a narrow strip of leather, which is attached to the upper portion of the shoe.
The ball is the widest part of the sole and should correspond to the area beneath the metatarsal heads. The portion of the sole between the ball and anterior border of the heel is the shank area. The shank piece is a rigid strip, preferably corrugated metal, which reinforces the shank area for resisting the stress imposed on the shank during ambulation.
A shank stiffens the shoe under the arch which makes the middle portion of the shoe more resistant to torsion and flexion.
The space between the anterior portion of the sole and the floor is referred to as “toe spring”. Toe spring allows a rocker effect which facilitates toe-off and reduces wrinkling of the upper part of the shoe.
The heel consists of two parts: the proximal section, made of firm leather, and the distal section, or the plantar surface, which contacts the ground. The plantar surfaces of most men’s heels are of medium or soft rubber, while women’s and children’s are of hard rubber.
The contours of the heel affect the function of the shoe. The with the anterior surface of the heel referred to as the breast, located further forward will increase the base of support for the foot.
Heel height is important for foot function. The heel is measured from the outer sole to the plantar surface of the heel.
Orthotists measures elevation at the center of the heel at a point corresponding to the calcaneal tuberosity.
Usually the higher the heel, the greater the pitch and consequently the more narrow the bearing surface on the foot. The pitch of the heel is the inclination of the posterior surface of the heel from the vertical. The military heel is approximately 31 mm high, the highest heel suitable for most orthopedic purposes is the Cuban heel, generally 38 mm high.
The portion of the shoe above the sole is called the upper, which consists of an anterior section (the vamp), and a posterior section (the quarters). The lateral quarter should be cut low enough to avoid abrading the more distally located lateral malleolus.
The tongue is the strip of leather lying under the laces. At the base of the tongue is the throat. Eyelets for the laces are contained in the lace stay which may be part of the vamp, depending on the style of the shoe.
Linings and Reinforcements
All portions of the shoe which contact the foot should be smoothly lined. A cotton vamp lining absorbs perspiration. The inner-sole lining and quarter linings may be made of leather or cotton reinforced with leather. They protect the foot and hose from contact with rougher surfaces of the leather and the stitching.
The vamp is reinforced by the toe box which guards the dorsum of the toes against trauma from falling objects and protects the tips of the toes from stubbing against furniture, rocks, or other obstacles. The toe box also preserves the contour of the vamp.
The counter is a leather, fiber, or Celastic reinforcement which preserves the shape of the shoe in the area of the anatomic heel.
The last is a model of the weight-bearing foot. Therefore, the comfort and walking characteristics of the shoe depending on the last.
It can be curved, semicurved or straight.
Outflare lasts are designed to accommodate fixed valgus deformity. The inflare last is designed for the opposite purpose, namely, to adduct the juvenile valgus forefoot, or to accommodate the adult fixed varus deformity.
Custom lasts are specifically constructed for a particular foot.
This refers to the height of the posterior portion of the upper.
The low shoe, or Oxford, is one in which the quarters extend to a level just below the malleoli.
The shoe is more cosmetic and does not restrict ankle and subtalar motion.
A shoe which covers the malleoli reduces piston action and grips the foot better than the low quarter resisting back-and-forth sliding of the foot.
The design of the throat portion of the shoe upper influences the ease of donning the shoe and the amount of adjustability of the shoe.
Most orthopedic shoes have the blucher-throat style, distinguished by the loose anterior margin of the lace stays. The quarters thus lie over the vamp and contain the lace stays. Blucher style provides a substantial opening which facilitates donning, and offers a greater degree of adjustment.
If donning is not a problem, the patient may wear the Balmoral or Bal style in which the vamp covers the forward edges of the quarters. The Bal shoe does not permit reflecting the tongue completely to open the shoe widely over the forefoot.
It an adaptation of the Blucher-throat style. The lace stays extend to the toe. This style, sometimes termed “surgical boot”, is easiest to don because the patient’s toes may be exposed fully. The lace-to-toe shoe may have high or low quarters.
Donning the shoe is facilitated by the type of closures as well as the throat style.
It is the usual shoe closure where cotton lacing is inserted into a minimum of four or, preferably, five pairs of eyelets. The laces permit the wearer to alter the snugness of the vamp to accommodate swelling or temporarily tender portions.
The patient’s impaired hand function or limitation of elbow or knee motion may need elastic shoelaces may be required. Once tied, the flexible laces need not be untied whenever the patient removes or dons the shoe.
Velcro flaps can be managed by one with poor coordination.
Non- adjustable closures
Zippers require minimal dexterity and leg agility, but they cannot be adjusted by the patient. A shoe with elastic-webbing inserts is even easier to don.
Construction of Shoe
Although there are many ways of manufacturing a shoe, Goodyear welt construction is recommended for orthopedic purposes as this method of manufacturing produces a shoe which is absolutely smooth inside and is easiest to alter with external modifications.
Evaluation of Shoe Fit
Every shoe should be evaluated for proper fit. The final fit is determined during the weight-bearing after all orthotic modifications have been completed.
Normally, there should be adequate room for the foot to expand upon weight-bearing. The shoe should be at least 13 mm longer than the longest toe, in order to facilitate toe-off action. The widest part of the shoe should coincide with the broadest part of the foot. The well-fitted shoe is snug from the heel to the ball of the foot. The heel-to-ball dimensions of the foot and the shoe, therefore, should be equal.
The quarters should not gap excessively. Undue gapping usually signifies a shank which is too narrow. Slight gapping is usual at heel strike but should disappear at midstance. The restriction of dorsiflexion by a dorsiflexion stop on the orthosis may produce some unavoidable gapping later instance. There will always be slight gapping and piston action because of the structural rigidity of the shoe. A counter which fits closely around the anatomic heel minimizes excessive motion of the foot in the shoe.
The purpose of the shoe would also determine the fit. Occasionally, a shoe should be fitted using the three-point pressure system to control and position a deformed foot or sometimes the shoe may be fitted to relieve pressure in given areas.