Orthopedic Heel

Abstract

The heel is designed to provide a rotational stress to the leg of the wearer during walking without providing stress to the foot when standing. An orthopedic heel is provided which is particularly suitable for correcting internal tibial torsion or hip anteversion. The heel includes a pair of side surfaces with one of the side surfaces extending posteriorly beyond the other side surface and an inclined or beveled planar posterior surface which extends angularly between the side surfaces. The rearwardmost portion of the inclined posterior surface provides a strike portion which engages the ground first during the heel strike phase of the wearer's gait and tends to rotate the lower extremity to bring the planar posterior surface of the heel into full engagement with the ground. The heel is provided with planar parallel upper and lower surfaces so that no undesirable stresses are provided to a normal foot during standing when the lower surface of the heel engages the ground.

Description

BACKGROUND

This invention relates to an orthopedic heel, and, more particularly, to an orthopedic heel intended for use in correcting internal tibial torsion or hip anteversion.

During the growth phase of life from birth to full growth the soft growing bones of the lower extremities are responsive to stresses and strains and may be subject to deformity as a result of undesirable stress and strain. One example of deformity resulting from stress and strain of a rotational nature is the child with the so-called pigeon-toed gait with a normal foot. Such a child may have either a tibial torsion or an anteversion of the hips. With tibial torsion the major bones of the lower legs are twisted toward each other, and when the kneecap points straight ahead, the feet point toward each other. With anteversion of the hips, there is an abnormality of the upper portion of the femur (thigh bone). When the upper portion of the femur (the so-called head and neck) is in normal position, the lower portion of the femur (the shaft of the femur) is twisted toward the opposite femur.

Both of the aforementioned deformities may be the result of improper sitting. Because of increased incidents of these conditions in recent years attributable to the growing child sitting on the floor for prolonged periods while watching television, the term "television legs" has been coined. With tibial torsion, the child may sit with his legs curled under him and place his weight on the lower legs to produce the rotational strain that creates the deformity. The condition of hip anteversion is usually created by the forces present when a child sits with his knees together pointed toward each other and his lower legs and feet extending toward either side. This produces an undesirable rotational stress on the upper leg bone (the femur) which is responsive to rotational stress and strain and results in deformity with twisting of the femurs toward each other.

A pigeon-toed gait may be due to other causes, such as deformities in the foot. For example, abnormalities in the foot may cause the fore-foot to bend toward the other foot when the hind foot is in normal relationship to the ankle. This condition is known as metatarsus varus. Treatment of this condition requires modifications of the shoe to provide a corrective stress to the foot. Outflare shoes are available which appear as though the child has the right shoe on the left foot. In addition, an outer sole wedge may be applied to the shoe which tends to exert a corrective force upon the foot.

Since pigeon-toed gait caused by internal tibial torsion or hip anteversion may occur in a child having a completely normal foot, it is desirable that corrective means for these deformities do not have an undesirable effect on the foot. Present corrective measures applied to the shoe often consist of an elevation on the outer sole of the shoe, the outer heel of the shoe, or both. It is noteworthy that these elevations or lifts function when the the is bearing full weight on the foot and produce little rotational stress on the lower extremity but transmit a stress to the foot similar to walking on the side of a hill (eversion) or a stress on the arch with consequent development of a "flat foot."

Although the foregoing discussion was directed specifically to abnormalities resulting in a pigeon-toed gait, it will be appreciated that another abnormality of gait is one in which the feet are directed too much away from each other, and the person has a so-called "duck walk." This results from an opposite rotational abnormality of the lower extremity.

SUMMARY

The invention provides for not only eliminating the deforming forces which will prevent further progression of rotational abnormalities but for reversal of the stresses which produce the deformities so that the deformities are corrected. The invention utilizes the principle that the human gait is a heel-toe gait, one of the phases of which is the "heel strike" phase in which the heel engages the walking surface before any other portion of the foot and before appreciable weight is transferred to the extremity. The inventive heel imparts a rotational stress to the foot which will be transferred to the lower extremity during the heel strike phase and produce a correction of the rotational deformity. The corrective rotational force is thereby provided during every step that is taken. The rearwardmost portion of the inclined posterior surface engages the walking surface first during the heel strike phase, and as weight is gradually transferred to the foot, the inclined posterior surface causes rotation of the heel and the foot to bring the posterior surface into full engagement with the walking surface. If the deformity results in a pigeon-toed gait, the medial side of the heel is made longer to produce a lateral rotational (pronator) effect. If the deformity causes a duck walk, the lateral side of the heel is made longer to provide a medial rotational (suppinator) effect. Since the rotational force is imparted to the foot during the heel strike phase before substantial weight is transferred to the foot, the rotational force will be transferred to the lower extremity. When full weight is transferred to the foot and the shoe is in complete contact with the walking surface, the posterior surface does not engage the walking surface, and no undesirable stresses are imparted to the foot.

DESCRIPTION OF THE DRAWING

The invention will be explained in conjunction with an illustrative embodiment shown in the accompanying drawing, in which:

FIG. 1 is a bottom plan view of a right shoe equipped with a heel formed in accordance with the invention;

FIG. 2 is a perspective view of the shoe and heel of FIG. 1;

FIG. 3 is a bottom plan view of the inventive heel;

FIG. 4 is a sectional view taken along the line 4--4 of FIG. 3;

FIG. 5 is a side elevational view showing the shoe and heel in the heel strike phase of the heel-toe gait;

FIG. 6 is a front elevational view of FIG. 5;

FIG. 7 is a view illustrating the movement of the shoe from the position of FIG. 6 caused by the posterior surface as additional weight is transferred to the foot; and

FIG. 8 is a fragmentary plan view of a shoe equipped with a heel which extends posteriorly of the curved rear contour of the sole.

DESCRIPTION OF SPECIFIC EMBODIMENT

Referring now to the drawing, a conventional shoe 10 having an upper 11 and a sole 12 is provided with a heel 13. The particular shoe 10 illustrated is a right shoe and includes a front or toe portion 14 and medial, i.e., adjacent the other foot, and lateral sides 15 and 16, respectively.

The heel 13 similarly includes generally vertically extending medial and lateral side surfaces 17 and 18, a concave front surface 19, and a rear or posterior flat surface 20. A flat upper surface 21 (FIG. 4) is secured to the sole 12 by conventional means, and a flat ground-engaging bottom surface 22 extends parallel to the top surface 21 to provide the heel with a uniform thickness from side to side and front to back.

The medial surface 17 of the heel extends posteriorly beyond the rear end of the lateral surface 18 so that the posterior surface 20 is inclined forwardly as it extends from the medial surface to the lateral surface. The posterior surface is also inclined from front to rear or posteriorly as it extends from the bottom surface to the top surface of the heel. The inclined posterior surface 20 is generally flat or planar, and the intersections of this flat surface with the planar, parallel top and bottom surfaces 21 and 22 provide straight, parallel upper and lower rear edges 23 and 24. The rear portion of each of the medial and lateral side surfaces curve inwardly somewhat to conform to the contour of the rear of the sole of the shoe, and the intersections or junctures of the inclined posterior surface with the side surfaces provide side edges 25 and 26 to the posterior surface.

The rear edges 23 and 24 of the posterior surface extend at an acute angle relative to a median line which extends along the longitudinal axis of the foot midway between the medial and lateral sides of the foot and the shoe. The upper rear edge 23 is straight, and in the particular embodiment illustrated the curved rear of the sole extends beyond the rear of the heel, which is completely within the contour of the heel.

The heel illustrated on the shoe 10 provides a pronator effect and is designed to correct a pigeon-toed gait by providing a lateral rotation to the foot during each step. Referring to FIGS. 5 and 6, as the heel strikes the ground, i.e., the walking surface, during the heel strike phase of the wearer's gait, the rearwardmost or strike portion of the heel adjacent the edge 25 contacts the ground first. As the toe portion of the foot moves toward the ground and more weight is transferred to the foot, the inclined posterior surface 20 will cause the shoe and the foot to move laterally or counterclockwise as viewed in FIG. 6 until the posterior surface comes into full bearing contact with the ground as illustrated in FIG. 7. Since this rotation is provided to the foot before any substantial weight is transferred to the foot, the rotation is transferred from the foot to the lower extremity. Thereafter, the foot can proceed through the remaining phases of the heel-toe gait.

The ground-engaging surface 22 of the heel is flat, and the heel does not provide rotational stress to the foot when the bottom surface of the heel is in contact with the ground, either during walking or during standing. Accordingly, if the wearer has a normal foot and the pigeon-toed gait is due to other causes such as internal tibial torsion or hip anteversion, no undesirable stresses are provided on the foot when the foot is supporting substantial weight which may harm the normal foot.

If the wearer's foot did have some abnormality which could be corrected by providing a wedge on the heel, the bottom surface 22 of the heel could be inclined relative to the upper surface to provide such a wedge while retaining the desirable rotational features of the posterior surface which operate during the heel strike phase.

In the particular embodiment illustrated in FIGS. 1 and 2, the heel is fully confined within the outer contour of the sole 12 and the lateral surface of the heel terminates forwardly of the rear of the sole. However, in severe cases requiring pronounced correction, the medial surface of the heel can be extended beyond the rear of the sole. This is shown in FIG. 8 in which the heel 113 having a flat rear surface 120 extends posteriorly of the curved rear edge 12a of the sole. The inclination of the edges 23 and 24 of the posterior surface relative to the median line of the heel and the inclination of the plane of the posterior surface relative to the bottom surface 22 can also be varied depending upon the amount of correction required. Thus, the position of the rear surface relative to the back of the shoe and the inclination of the plane of the rear surface relative to the median line and the bottom of the heel can all be varied depending upon the needs of the user.

The same heel 13 illustrated in FIG. 3 can be used to provide a suppinator or toe-in effect by securing the heel to the left shoe. In this case, the medial or inner surface of the heel would be the surface 18, and the lateral or outer side of the heel would be the surface 17. The strike portion of the heel would be on the lateral side, and the shoe and the feet would be rotated medially as the flat posterior surface is brought into full engagement with the ground.

While in the foregoing specification a detailed description of a specific embodiment of the invention was set forth for the purpose of illustration, it is to be understood that many of the details hereingiven may be varied considerably by those skilled in the art without departing from the spirit and scope of the invention.

Claims

I claim:

1. An orthopedic heel for providing rotational stress to the leg of the wearer during walking, the heel having an upper surface adapted to be attached to a shoe, a lower surface, medial and lateral side surfaces, and anterior and posterior surfaces extending between the side surfaces, the posterior surface being generally planar and being inclined posteriorly from the bottom surface to the top surface, one of the side surfaces extending posteriorly beyond the other side surface so that the posterior surface extends at an acute angle relative to a median line between the medial and lateral side surfaces, the posterior surface being provided with a strike portion adjacent the juncture between the posterior surface and said one side surface adapted to engage the ground first during walking and to rotate the heel toward said other side to bring the posterior surface into substantially full engagement with the ground.

2. The structure of claim 1 in which the upper and lower surfaces are generally planar and generally parallel whereby no undesirable stresses are provided to the foot during standing.

3. The structure of claim 2 in which the intersections of the planar posterior surface with the planar upper and lower surfaces provide upper and lower straight rear edges which extend at an acute angle with respect to the median line.

4. The structure of claim 1 in which said one side surface which extends posteriorly beyond the other side surface is the medial surface.

5. The structure of claim 1 in which said one side surface which extends posteriorly beyond the other side surface is the lateral surface.