Symposium on Common Orthopedic Problems
Shoes and Shoe Corrections Henry R. Cowell, M.D. *
Selection and correction of shoes is an important subject to all individuals who treat children. Unfortunately, it is also a subject of great controversy and an area in which few scientifically performed studies have been carried out. A discussion of the use of shoes and shoe corrections must be viewed, then, as an individual's approach to the problem, rather than as a documented treatise. Certain corrections relieve pain or immediately improve the gait, and many parents report a prolonged benefit. Whether these corrections alter a habit pattern or whether improvement is a result of the favorable natural history of the condition cannot be accurately determined.! No correction will improve a structural deformity of the foot. Children with normal feet need protection from the irregular surface of rough ground, from the hard surface of concrete, and in many areas of the country, from cold. In order to provide protection, the shoe must be constructed so that it will retain its fit, be flexible in the toe area, and be made of durable material. When corrections are applied to the shoe, special considerations are necessary in the manufacture of the shoe. The purpose of this presentation is to describe the components required in a shoe, the proper fitting of shoes, the type of shoes to be used by normal children, and the use of corrections in shoes for certain deformities.
Anatomy of the Shoe The last is the wooden form over which shoes are made. The last for a normal foot allows for slight inflaring in the area of the great toe. The last should have a round shape for the remaining toes so that there is sufficient room for the five toes to function normally and room for growth. The heel of the last is narrower than the area of the metatarsal heads. The shoe should be sufficiently narrow in the heel area so that the shoe will grasp the foot. The shoe must also allow sufficient room for the broad part of the foot in the area of the metatarsal heads. There must be sufficient area in the cone of the last-the area over the mid portion of the foot- so that a snug fit will be allowed without putting undue pressure on the dorsum of the foot. *Associate Surgeon-in-Chief, Alfred I. duPont Institute, Wilmington, Delaware Pediatric Clinics of North America- Vol. 24, No.4, November 1977
791
792
HENRY
R. COWELL
A shoe consists of the upper and the sole. The upper should be made of soft pliable material which allows for evaporation of moisture, thus leather is commonly selected. Materials that do not allow for evaporation, or polishes or waterproofing materials applied to the upper which prevent the leather or other material from "breathing," will cause the foot to perspire excessively. The portion of the upper which surrounds the heel is referred to as the counter. A shoe should have a firm counter that cannot be squeezed between the thumb and fingers. The normal counter surrounds the heel and extends anteriorly to the anterior end of the os calcis. The counter should fit the heel firmly. The use of a firm counter allows the shoe to retain its shape. When corrections are applied to the heel, a reinforced and extended inside (medial) counter is indicated to give additional support to the inside of the shoe (Fig. 1). The sole of the shoe is made up of the insole, a filler, and the outsole. The insole should be made of a pliable but durable material with some porosity to absorb moisture and permit evaporation. The outsole is
Figure 1.
Figure 2. Figure 1. The parts of a corrective shoe are identified. Note the medial heel wedge placed between the heel and the insole. A long inside medial counter is also shown. Figure 2. A triangular outer sole wedge is used for certain types of intoeing. The wedge should be 3(,6" at its thickest part and tapered to zero at the three corners.
SHOES AND SHOE CORRECTIONS
793
the material which strikes the ground and therefore must be durable and flexible. The shank area of the shoe is the area underneath the mid portion of the arch of the foot. A reinforced steel shank which has flexibility at the distal end allows support under the arch but allows flexibility of the toes. The shank normally extends from the undersurface of the middle part of the os calcis to the mid-shaft of the metatarsals. The welt is the edge of leather which is applied outside the upper and attached first to the insole and upper, and then to the outsole. Shoes that are to be used to apply corrections should have a chainstitch inseam which stitches the upper to the insole and the upper portion of the welt. A lockstitch outseam holds the insole and upper to the outsole. When corrections are to be applied to the shoe, the outsole may be split from the insole-upper combination to allow insertion of the wedge without damaging the basic construction of the shoe. Shoes that are constructed with the outsole attached to the insole by adhesive materials are not suitable for applying most corrections since it is difficult to re-cement the outsole to the insole completely after opening up the sole to apply a wedge. The final component of the shoe is the lining, usually of cloth, placed inside the shoe to absorb moisture and prevent friction. Shoes without cloth lining may create pressure areas on the foot resulting in blisters. Shoes without cloth linings are unable to handle moisture, thus creating an odor problem.
Shoes for Normal Children The infant requires shoes for protection only. During cool weather, a loose fitting shoe that keeps the foot warm is the only shoe required. In warm weather, no shoe is necessary. The pre-walker who is just beginning to stand should have a shoe with a firm heel counter, a soft flexible sole, and a soft leather top. The sole on a shoe for a pre-walker may be approximately l/S" thick and should be extremely flexible. The child at this age uses toe motion to push off and therefore it is important to have a flexible sole. When the child begins walking independently, a shoe with a firm counter and firm sole is indicated. The shoe at this time should have a sole approximately 1/4 " thick and may have a heel that is 1/4 " to 3/S" thick. All children's feet appear flat at birth because of excess fat in the arch area. Normally, children do not require high top shoes for support. Rather they require high top shoes until the foot has developed sufficiently that the foot will stay in the shoe. By the age of 21 months to 2 years the fat pad has atrophied sufficiently and the heel has obtained sufficient shape that the foot will fit into a low shoe without the heel slipping out. The shoe should still be quite flexible past the metatarsal heads. The walking child may wear a low shoe as soon as the heel fits the heel counter of the shoe sufficiently firmly that the heel of the shoe does not slip off and does not cause blisters. During the growing years from three to nine the child requires a shoe with a round toe to allow sufficient room for the toes. This shoe may have a heel which is 1/4" to 3/s" higher than the sole. A steel shank
794
HENRY
R.
COWELL
which gives support to the arch but also allows flexibility of the forepart of the foot is indicated. For a normal child a simple steel shank is indicated without a reinforcement. A rigid steel shank shoe is not indicated for the normal child. Because of excessive wear during this period, plastic polishes or waterproofing materials are often applied to the shoe. This material allows the shoe to breathe less well and therefore allows the shoe to retain moisture. Moisture allows fungus to grow in shoes and creates an odor problem. During the adolescent period the shoe should continue to have a shank which allows adequate support, especially for walking on hard surfaces. A leather upper continues to permit the shoe to breathe, and a firm counter keeps the shoe from breaking down as readily. While a variety of shoes are preferred by adolescents, wearing soft or inadequate shoes all the time may contribute to the problem of fungal infections and may cause aching in the feet because of inadequate protection. If teenagers have pain or aching in their feet because of prolonged walking or running on hard surfaces, then a shoe with adequate support is indicated.
Fitting of the Shoe The shoe must fit the foot properly in the heel and also must be of appropriate width and length. The heel should fit firmly into the heel counter, but should not be too snug. If the foot fits firmly into the counter, slipping is prevented, thus keeping the shoe on and holding the heel in alignment. If the heel counter of the shoe is too loose or too tight, blistering of the heel may occur. A new shoe should be approximately 112" longer than the longest toe when it is fit to the child's foot. The upper should be sufficiently flexible so that the toe box can be squeezed when the child is standing to determine that there is 1/2 " between the end of the toe and the end of the toe box. The width of the shoe at the widest part of the foot-the area of the metatarsal head-should be such that the leather is flexible and not stretched over the dorsum of the foot. When the shoe is fitted properly and new, it should be possible to pick up a small dimple of the leather on the dorsum of the foot over the area of the metatarsal heads. As the individual is growing, shoes need to be replaced when the toes approach the end of the shoe, when the toes appear to press up into the area of the toe box, when the widest part of the foot spreads the top of the shoe, and when the shoe loses its shape.
SHOE CORRECTIONS Lasts While numerous corrections have been described for the shoe,S a few basic corrections constitute the vast majority of corrections for children's problems. The last of the shoe may be altered from a regular last to a straight last or an outflare last. Children who have undergone cast treatment for turning in of the forefoot frequently are placed in a straight last shoe following cast correction. Even an outflare shoe is in-
• SHOES AND SHOE CORRECTIONS
795
dicated in certain instances. These shoes are used following correction with a cast in order to maintain the correction, not to obtain correction by themselves.
Flat Feet Certain children who have fiat feet require treatment. Infants with specific problems such as calcaneovalgus feet or vertical talus should be recognized immediately and treated appropriately.' Similarly, children with rigid fiat feet should be properly recognized. 2 Children with fiexible fiat feet may be divided into distinct categories. One group of children has tightness of the heel cord. If the heel cord is tight when the foot is brought into inversion, stretching exercises or casting will alleviate the problem. Children who have a foot that is fiat when they are standing and an arch when they are sitting may be treated with a Thomas heel, medial heel wedge and/or a medial arch support. In this group of patients, this treatment will not do any harm and may allow the arch to develop over a period of time. Using a correction for this condition during the ages from two to six has not been proved scientifically, but the author believes it is worthwhile when the foot is quite fiat. Individuals with a fiexible fiat foot but without an arch either when standing or sitting have constitutional fiat feet which will not be benefited by shoe correction. In fact, applying corrections only tends to aggravate the pain by putting pressure underneath the arch when no arch is present. Another group of children with fiat feet have pain in the leg which frequently occurs in the evening after a long day of activity and often is relieved by having the mother rub the area over the anterior tibial muscle belly. This foot pain can be relieved dramatically with a Thomas heel and a medial heel wedge. This is the most appropriate use of this modality of treatment. Children will respond within two or three days to such support. The medial heel wedge is applied to the inner side of the heel of the shoe. Up to age two, this wedge should be approximately 1116" at the medial portion, tapering to zero laterally. From age two until age five, a 1/8" medial heel wedge may be applied. After age five, a 3116" medial heel wedge may be applied. The wedge is placed between the outsole and the insole. A medial arch support or medial "cookie" of 1/8" to 1/4" in thickness may be placed under the arch in the area just medial to the anterior portion of the calcaneus and underneath the head of the talus. The medial heel wedge serves two purposes. It allows the heel to be brought into a more neutral position from the valgus position. This will occur only if an extended inside (medial) counter is used and the shoe fits the foot satisfactorily. It also serves as a fulcrum point in ambulation when the foot strikes the ground. As the foot is carried forward, a medial heel wedge with an extended heel, known as a Thomas heel (Fig. 1), acts as a fulcrum for the foot to rotate inward. This is used in children who have fiat feet and also in children who tend to ambulate with their feet turned out. These corrections, while they will improve the foot with ambulating when the correction is applied, may not have lasting effect when the correction is removed from the shoe.
796
HENRY
R.
COWELL
Knock Knees and Bow Legs Children with knock knees may be fitted with a shoe with a medial heel and sole wedge (3ils"). Wedges applied on the medial aspect of the heel and sole theoretically tend to redirect the force at the area of the knee to take stress off the lateral aspect of the epiphyseal growth areas of the proximal tibia and distal femur. Decreasing this stress may allow differential increase in growth, thus correcting the deformity. Only mild deformities should be followed in this manner. More severe problems may require night or even day bracing of the extremities. Bow legs may be treated by applying the corrections to the lateral side of the heel and sole. The wedges theoretically redistribute the force so that more stress is placed on the lateral epiphyseal lines at the knee, thus slowing growth and allowing correction of the bow leg deformity. This theoretic reason for the use of wedges has not been documented by scientific studies. It is apparent that this wedge may be used as a palliative form of treatment while the natural course of the disease may be evaluated. Moreover, the clinician should be aware of the changes seen in more severe bowing, such as Blount's disease, and treat the child with the appropriate bracing methods. Intoeing Intoeing may occur from increased femoral anteversion,3 increased internal tibial torsion,6 metatarsus adductus,5 and postural problems. While the corrections described below are used in all of the above conditions, tibial torsion is better treated by night splints and metatarsus adductus by casting. Increased anteversion tends to improve with age, is little helped by the shoe corrections, and may require surgical correction in very limited circumstances. Corrections applied for intoeing include the Torqheel, the triangular outer sole wedge (Fig. 2), and the lateral sole wedge. The Torqheel functions by allowing the foot to rotate externally at the heel when the heel strikes the ground. The triangular outer sole wedge allows the child to turn out with ambulation because the child strikes the wedge while ambulating and voluntarily turns the foot into abduction and external rotation to avoid striking this triangular sole wedge. A third method is the lateral sole wedge, normally 3/d', which functions by externally rotating the foot slightly through the subtalar joint, thus taking the forefoot into valgus. Recent work7 has shown that the Torqheel seems to be the most effective method of externally rotating the foot but studies have not been done with the triangular outer sole wedge. However, even use of the Torqheel creates an immediate correction of only 25 per cent. This improvement may not be maintained once the correction has been removed from the shoes. Conclusion The subject of shoe corrections is an area in which very little work has been done to substantiate the benefits. While certain corrections are indicated in specific clinical abnormalities, they are seldom indicated in children who have mild relaxed flat feet. It has been shown that wedges will affect the rotation of the foot by altering the position of the subtalar
797
SHOES AND SHOE CORRECTIONS
joint, but it has not been documented· that these changes will be maintained after the corrections have been removed. When corrections are applied to shoes of younger children, they should not be applied for a lifelong period but rather should be removed at five to seven years of age.
REFERENCES 1. Bleck, E. E.: The shoeing of children-Sham or science? Dev. Med. Child. Neurol.,13:188195, 1971. 2. Cowell, H. R.: Diagnosis and management of peroneal spastic flatfoot. American Academy of Orthopaedic Surgeons Instructional Course, Vol. 24, pp. 94-103, St. Louis, C. V. Mosby Co., 1975. 3. Fabry, G., MacEwen, G. D., and Shands, A. R., Jr.: Torsion of the femur. J. Bone Joint Surg., 55A:1726-1738, 1973. 4. Giannestras, N. J.: Recognition and treatment of flatfeet in infancy. Clin. Orthop., 70:1029,1970. 5. Kite, J. H.: Torsion ofthe lower extremities in small children. J. Bone Joint Surg., 36A :511520,1954. 6. Knight, R. A.: Developmental deformities of the lower extremities. J. Bone Joint Surg., 36A:521-527, 1954. 7. Knittel, G., and Staheli, L. T.: The effectiveness of shoe modifications for in-toeing. Orthop. Clin. North Am., 7:1019-1025, 1976. 8. Wickstrom, J., and Williams, R. A.: Shoe corrections and orthopaedic foot supports. Clin. Orthop., 70:30-42, 1970. Alfl'ed I. duPont Institute Box 269 Wilmington, Delaware 19899
Shoes and Shoe Corrections Henry R. Cowell, M.D. *
Selection and correction of shoes is an important subject to all individuals who treat children. Unfortunately, it is also a subject of great controversy and an area in which few scientifically performed studies have been carried out. A discussion of the use of shoes and shoe corrections must be viewed, then, as an individual's approach to the problem, rather than as a documented treatise. Certain corrections relieve pain or immediately improve the gait, and many parents report a prolonged benefit. Whether these corrections alter a habit pattern or whether improvement is a result of the favorable natural history of the condition cannot be accurately determined.! No correction will improve a structural deformity of the foot. Children with normal feet need protection from the irregular surface of rough ground, from the hard surface of concrete, and in many areas of the country, from cold. In order to provide protection, the shoe must be constructed so that it will retain its fit, be flexible in the toe area, and be made of durable material. When corrections are applied to the shoe, special considerations are necessary in the manufacture of the shoe. The purpose of this presentation is to describe the components required in a shoe, the proper fitting of shoes, the type of shoes to be used by normal children, and the use of corrections in shoes for certain deformities.
Anatomy of the Shoe The last is the wooden form over which shoes are made. The last for a normal foot allows for slight inflaring in the area of the great toe. The last should have a round shape for the remaining toes so that there is sufficient room for the five toes to function normally and room for growth. The heel of the last is narrower than the area of the metatarsal heads. The shoe should be sufficiently narrow in the heel area so that the shoe will grasp the foot. The shoe must also allow sufficient room for the broad part of the foot in the area of the metatarsal heads. There must be sufficient area in the cone of the last-the area over the mid portion of the foot- so that a snug fit will be allowed without putting undue pressure on the dorsum of the foot. *Associate Surgeon-in-Chief, Alfred I. duPont Institute, Wilmington, Delaware Pediatric Clinics of North America- Vol. 24, No.4, November 1977
791
792
HENRY
R. COWELL
A shoe consists of the upper and the sole. The upper should be made of soft pliable material which allows for evaporation of moisture, thus leather is commonly selected. Materials that do not allow for evaporation, or polishes or waterproofing materials applied to the upper which prevent the leather or other material from "breathing," will cause the foot to perspire excessively. The portion of the upper which surrounds the heel is referred to as the counter. A shoe should have a firm counter that cannot be squeezed between the thumb and fingers. The normal counter surrounds the heel and extends anteriorly to the anterior end of the os calcis. The counter should fit the heel firmly. The use of a firm counter allows the shoe to retain its shape. When corrections are applied to the heel, a reinforced and extended inside (medial) counter is indicated to give additional support to the inside of the shoe (Fig. 1). The sole of the shoe is made up of the insole, a filler, and the outsole. The insole should be made of a pliable but durable material with some porosity to absorb moisture and permit evaporation. The outsole is
Figure 1.
Figure 2. Figure 1. The parts of a corrective shoe are identified. Note the medial heel wedge placed between the heel and the insole. A long inside medial counter is also shown. Figure 2. A triangular outer sole wedge is used for certain types of intoeing. The wedge should be 3(,6" at its thickest part and tapered to zero at the three corners.
SHOES AND SHOE CORRECTIONS
793
the material which strikes the ground and therefore must be durable and flexible. The shank area of the shoe is the area underneath the mid portion of the arch of the foot. A reinforced steel shank which has flexibility at the distal end allows support under the arch but allows flexibility of the toes. The shank normally extends from the undersurface of the middle part of the os calcis to the mid-shaft of the metatarsals. The welt is the edge of leather which is applied outside the upper and attached first to the insole and upper, and then to the outsole. Shoes that are to be used to apply corrections should have a chainstitch inseam which stitches the upper to the insole and the upper portion of the welt. A lockstitch outseam holds the insole and upper to the outsole. When corrections are to be applied to the shoe, the outsole may be split from the insole-upper combination to allow insertion of the wedge without damaging the basic construction of the shoe. Shoes that are constructed with the outsole attached to the insole by adhesive materials are not suitable for applying most corrections since it is difficult to re-cement the outsole to the insole completely after opening up the sole to apply a wedge. The final component of the shoe is the lining, usually of cloth, placed inside the shoe to absorb moisture and prevent friction. Shoes without cloth lining may create pressure areas on the foot resulting in blisters. Shoes without cloth linings are unable to handle moisture, thus creating an odor problem.
Shoes for Normal Children The infant requires shoes for protection only. During cool weather, a loose fitting shoe that keeps the foot warm is the only shoe required. In warm weather, no shoe is necessary. The pre-walker who is just beginning to stand should have a shoe with a firm heel counter, a soft flexible sole, and a soft leather top. The sole on a shoe for a pre-walker may be approximately l/S" thick and should be extremely flexible. The child at this age uses toe motion to push off and therefore it is important to have a flexible sole. When the child begins walking independently, a shoe with a firm counter and firm sole is indicated. The shoe at this time should have a sole approximately 1/4 " thick and may have a heel that is 1/4 " to 3/S" thick. All children's feet appear flat at birth because of excess fat in the arch area. Normally, children do not require high top shoes for support. Rather they require high top shoes until the foot has developed sufficiently that the foot will stay in the shoe. By the age of 21 months to 2 years the fat pad has atrophied sufficiently and the heel has obtained sufficient shape that the foot will fit into a low shoe without the heel slipping out. The shoe should still be quite flexible past the metatarsal heads. The walking child may wear a low shoe as soon as the heel fits the heel counter of the shoe sufficiently firmly that the heel of the shoe does not slip off and does not cause blisters. During the growing years from three to nine the child requires a shoe with a round toe to allow sufficient room for the toes. This shoe may have a heel which is 1/4" to 3/s" higher than the sole. A steel shank
794
HENRY
R.
COWELL
which gives support to the arch but also allows flexibility of the forepart of the foot is indicated. For a normal child a simple steel shank is indicated without a reinforcement. A rigid steel shank shoe is not indicated for the normal child. Because of excessive wear during this period, plastic polishes or waterproofing materials are often applied to the shoe. This material allows the shoe to breathe less well and therefore allows the shoe to retain moisture. Moisture allows fungus to grow in shoes and creates an odor problem. During the adolescent period the shoe should continue to have a shank which allows adequate support, especially for walking on hard surfaces. A leather upper continues to permit the shoe to breathe, and a firm counter keeps the shoe from breaking down as readily. While a variety of shoes are preferred by adolescents, wearing soft or inadequate shoes all the time may contribute to the problem of fungal infections and may cause aching in the feet because of inadequate protection. If teenagers have pain or aching in their feet because of prolonged walking or running on hard surfaces, then a shoe with adequate support is indicated.
Fitting of the Shoe The shoe must fit the foot properly in the heel and also must be of appropriate width and length. The heel should fit firmly into the heel counter, but should not be too snug. If the foot fits firmly into the counter, slipping is prevented, thus keeping the shoe on and holding the heel in alignment. If the heel counter of the shoe is too loose or too tight, blistering of the heel may occur. A new shoe should be approximately 112" longer than the longest toe when it is fit to the child's foot. The upper should be sufficiently flexible so that the toe box can be squeezed when the child is standing to determine that there is 1/2 " between the end of the toe and the end of the toe box. The width of the shoe at the widest part of the foot-the area of the metatarsal head-should be such that the leather is flexible and not stretched over the dorsum of the foot. When the shoe is fitted properly and new, it should be possible to pick up a small dimple of the leather on the dorsum of the foot over the area of the metatarsal heads. As the individual is growing, shoes need to be replaced when the toes approach the end of the shoe, when the toes appear to press up into the area of the toe box, when the widest part of the foot spreads the top of the shoe, and when the shoe loses its shape.
SHOE CORRECTIONS Lasts While numerous corrections have been described for the shoe,S a few basic corrections constitute the vast majority of corrections for children's problems. The last of the shoe may be altered from a regular last to a straight last or an outflare last. Children who have undergone cast treatment for turning in of the forefoot frequently are placed in a straight last shoe following cast correction. Even an outflare shoe is in-
• SHOES AND SHOE CORRECTIONS
795
dicated in certain instances. These shoes are used following correction with a cast in order to maintain the correction, not to obtain correction by themselves.
Flat Feet Certain children who have fiat feet require treatment. Infants with specific problems such as calcaneovalgus feet or vertical talus should be recognized immediately and treated appropriately.' Similarly, children with rigid fiat feet should be properly recognized. 2 Children with fiexible fiat feet may be divided into distinct categories. One group of children has tightness of the heel cord. If the heel cord is tight when the foot is brought into inversion, stretching exercises or casting will alleviate the problem. Children who have a foot that is fiat when they are standing and an arch when they are sitting may be treated with a Thomas heel, medial heel wedge and/or a medial arch support. In this group of patients, this treatment will not do any harm and may allow the arch to develop over a period of time. Using a correction for this condition during the ages from two to six has not been proved scientifically, but the author believes it is worthwhile when the foot is quite fiat. Individuals with a fiexible fiat foot but without an arch either when standing or sitting have constitutional fiat feet which will not be benefited by shoe correction. In fact, applying corrections only tends to aggravate the pain by putting pressure underneath the arch when no arch is present. Another group of children with fiat feet have pain in the leg which frequently occurs in the evening after a long day of activity and often is relieved by having the mother rub the area over the anterior tibial muscle belly. This foot pain can be relieved dramatically with a Thomas heel and a medial heel wedge. This is the most appropriate use of this modality of treatment. Children will respond within two or three days to such support. The medial heel wedge is applied to the inner side of the heel of the shoe. Up to age two, this wedge should be approximately 1116" at the medial portion, tapering to zero laterally. From age two until age five, a 1/8" medial heel wedge may be applied. After age five, a 3116" medial heel wedge may be applied. The wedge is placed between the outsole and the insole. A medial arch support or medial "cookie" of 1/8" to 1/4" in thickness may be placed under the arch in the area just medial to the anterior portion of the calcaneus and underneath the head of the talus. The medial heel wedge serves two purposes. It allows the heel to be brought into a more neutral position from the valgus position. This will occur only if an extended inside (medial) counter is used and the shoe fits the foot satisfactorily. It also serves as a fulcrum point in ambulation when the foot strikes the ground. As the foot is carried forward, a medial heel wedge with an extended heel, known as a Thomas heel (Fig. 1), acts as a fulcrum for the foot to rotate inward. This is used in children who have fiat feet and also in children who tend to ambulate with their feet turned out. These corrections, while they will improve the foot with ambulating when the correction is applied, may not have lasting effect when the correction is removed from the shoe.
796
HENRY
R.
COWELL
Knock Knees and Bow Legs Children with knock knees may be fitted with a shoe with a medial heel and sole wedge (3ils"). Wedges applied on the medial aspect of the heel and sole theoretically tend to redirect the force at the area of the knee to take stress off the lateral aspect of the epiphyseal growth areas of the proximal tibia and distal femur. Decreasing this stress may allow differential increase in growth, thus correcting the deformity. Only mild deformities should be followed in this manner. More severe problems may require night or even day bracing of the extremities. Bow legs may be treated by applying the corrections to the lateral side of the heel and sole. The wedges theoretically redistribute the force so that more stress is placed on the lateral epiphyseal lines at the knee, thus slowing growth and allowing correction of the bow leg deformity. This theoretic reason for the use of wedges has not been documented by scientific studies. It is apparent that this wedge may be used as a palliative form of treatment while the natural course of the disease may be evaluated. Moreover, the clinician should be aware of the changes seen in more severe bowing, such as Blount's disease, and treat the child with the appropriate bracing methods. Intoeing Intoeing may occur from increased femoral anteversion,3 increased internal tibial torsion,6 metatarsus adductus,5 and postural problems. While the corrections described below are used in all of the above conditions, tibial torsion is better treated by night splints and metatarsus adductus by casting. Increased anteversion tends to improve with age, is little helped by the shoe corrections, and may require surgical correction in very limited circumstances. Corrections applied for intoeing include the Torqheel, the triangular outer sole wedge (Fig. 2), and the lateral sole wedge. The Torqheel functions by allowing the foot to rotate externally at the heel when the heel strikes the ground. The triangular outer sole wedge allows the child to turn out with ambulation because the child strikes the wedge while ambulating and voluntarily turns the foot into abduction and external rotation to avoid striking this triangular sole wedge. A third method is the lateral sole wedge, normally 3/d', which functions by externally rotating the foot slightly through the subtalar joint, thus taking the forefoot into valgus. Recent work7 has shown that the Torqheel seems to be the most effective method of externally rotating the foot but studies have not been done with the triangular outer sole wedge. However, even use of the Torqheel creates an immediate correction of only 25 per cent. This improvement may not be maintained once the correction has been removed from the shoes. Conclusion The subject of shoe corrections is an area in which very little work has been done to substantiate the benefits. While certain corrections are indicated in specific clinical abnormalities, they are seldom indicated in children who have mild relaxed flat feet. It has been shown that wedges will affect the rotation of the foot by altering the position of the subtalar
797
SHOES AND SHOE CORRECTIONS
joint, but it has not been documented· that these changes will be maintained after the corrections have been removed. When corrections are applied to shoes of younger children, they should not be applied for a lifelong period but rather should be removed at five to seven years of age.
REFERENCES 1. Bleck, E. E.: The shoeing of children-Sham or science? Dev. Med. Child. Neurol.,13:188195, 1971. 2. Cowell, H. R.: Diagnosis and management of peroneal spastic flatfoot. American Academy of Orthopaedic Surgeons Instructional Course, Vol. 24, pp. 94-103, St. Louis, C. V. Mosby Co., 1975. 3. Fabry, G., MacEwen, G. D., and Shands, A. R., Jr.: Torsion of the femur. J. Bone Joint Surg., 55A:1726-1738, 1973. 4. Giannestras, N. J.: Recognition and treatment of flatfeet in infancy. Clin. Orthop., 70:1029,1970. 5. Kite, J. H.: Torsion ofthe lower extremities in small children. J. Bone Joint Surg., 36A :511520,1954. 6. Knight, R. A.: Developmental deformities of the lower extremities. J. Bone Joint Surg., 36A:521-527, 1954. 7. Knittel, G., and Staheli, L. T.: The effectiveness of shoe modifications for in-toeing. Orthop. Clin. North Am., 7:1019-1025, 1976. 8. Wickstrom, J., and Williams, R. A.: Shoe corrections and orthopaedic foot supports. Clin. Orthop., 70:30-42, 1970. Alfl'ed I. duPont Institute Box 269 Wilmington, Delaware 19899
