Forefoot Orthotic Device

Abstract

A forefoot orthotic device has multiple regions configured so that impact, propulsive or standing forces experienced by the forefoot of the user are accelerated, decelerated, shifted, transferred, or lessened, so as to promote pain reduction or otherwise address or treat conditions of the forefoot. In one implementation, the device includes expanded areas adapted to underlie the first and fifth metatarsal heads and cushion or offload forces therefrom. In still other variations, the device includes a plateau and regions adjacent the plateau and sloping downwardly therefrom, so that the time during which painful regions of the forefoot experience force, such as during gait or standing, is lessened in favor of transferring such forces to adjacent regions which potentially are less in need of treatment or protection from such forces.

1 . A forefoot orthotic device for use in connection with a user's foot, the user's foot characterized by a forefoot and metatarsal heads one through five, the device comprising:
 an element sized and shaped to underlie the forefoot, the element having opposite upper and lower surfaces, opposite proximal and distal ends, opposite lateral and medial sides, and resiliently compressible material extending between the opposite surfaces, the opposite ends and the opposite sides;   wherein the element has a central longitudinal axis, the lower surface of the element having at least three points defining a lower plane of reference for the element when the device is in use;   wherein the lateral and medial sides have respective side edges, the lateral and medial side edges located further from the central longitudinal axis at the distal end than at the proximal end to define two, expanded areas located at the lateral and medial sides, respectively, on the distal end of the element;   wherein the expanded areas are laterally spaced from each other by a predetermined amount between 2.5 inches to 3.5 inches, the predetermined amount corresponding to the distance between the first and fifth metatarsal heads of the user's foot having a predetermined size ranging from child size 1 to adult male size 16; and   wherein the upper surface extends upwardly and inwardly from the opposite ends and the opposite sides to define corresponding, opposite proximal and distal areas, and opposite lateral and medial areas, the areas having central portions defining a plateau raised relative to the lower plane of reference.   
     
     
         2 . The device of  claim 1 , wherein the lateral and medial areas extend transversely in an arch from the lateral and medial side edges, the arch having a radius of curvature ranging from 80 mm to 110 mm. 
     
     
         3 . The device of  claim 2 , wherein the top of the arch is located in the plateau. 
     
     
         4 . The device of  claim 1 , wherein the resiliently compressible material of the element is configured so that the lateral and medial areas are more rigid than portions of the proximal area adjacent the medial and lateral areas, whereby, during use, deceleration of the foot portions overlying the medial and lateral areas is greater than deceleration of foot portions overlying the adjacent portions of the proximal area. 
     
     
         5 . The device of  claim 4 , wherein the resiliently compressible material under the medial and lateral areas is thicker than the resiliently compressible material under the adjacent portions of the proximal area. 
     
     
         6 . The device of  claim 5 , wherein the thicker resiliently compressible material of the medial and lateral areas terminates in an upper edge relatively higher than the adjacent portions of the proximal area to define an uphill region on the upper surface of the element. 
     
     
         7 . The device of  claim 1 , wherein the resiliently compressible material of the element is configured so that the medial and lateral areas are more rigid than portions of the distal area adjacent the medial and lateral areas, whereby, during use, acceleration of forefoot portions overlying the distal area is greater than acceleration of forefoot portions overlying the medial and lateral areas. 
     
     
         8 . The device of  claim 1 , wherein a lower surface has an outer circumference and extends inwardly and upwardly therefrom relative to the lower plane of reference to define a concavity, and wherein the resiliently compressible material is configured so that weight associated with the user deflects the concavity toward the lower plane of reference. 
     
     
         9 . The device of  claim 8 , wherein the resiliently compressible material is configured to have a thickness ranging between 4 mm and 6 mm, a durometer, according to the 00 scale, ranging from 20 to 80, and wherein the concavity is defined to have a radius ranging from 16 mm to 22 mm and a maximum depth ranging from 4 mm to 6 mm, whereby the concavity returns from a deflected position during impact phase of the gait cycle to an un-deflected position after toe-off phase of the gait cycle. 
     
     
         10 . The device of  claim 1 , comprising:
 an insole sized and shaped to underlie the foot of the user from the heel of the user, the insole extending from the heel distally by an amount ranging from 20 cm to 31.8 cm sufficient to underlie at least the metatarsal heads of the user's foot; and   wherein the element is secured to the insole in a location to underlie the forefoot of the user when the device is in use.   
     
     
         11 . The device of  claim 10 , wherein the element is integrated with the insole. 
     
     
         12 . The device of  claim 11 , wherein the insole includes a first portion underlying the heel and having a first predetermined durometer and a second portion underlying the sagittal arch of the mid-foot and having a second predetermined durometer, and wherein the second predetermined durometer is greater than the first predetermined durometer by amounts ranging between 10 and 20. 
     
     
         13 . The device of  claim 1 , further comprising a sleeve sized and shaped to be worn about the forefoot of the user, wherein the element is secured to the sleeve in a location to underlie the forefoot of the user when the device is in use. 
     
     
         14 . The device of  claim 1 , further comprising:
 footwear selected from the group consisting of a shoe, boot, brace and cast, the footwear having a sole for receiving the user's foot in an overlying relationship;   wherein the element is operatively associated with the sole of the footwear to underlie the forefoot of the user when the foot is placed in the footwear.   
     
     
         15 . The device of  claim 14 , wherein the footwear includes an insole, and wherein the element is secured to or integrated with the insole. 
     
     
         16 . A forefoot orthotic device for use in connection with a user's foot, the device comprising:
 a resiliently compressible material extending between upper and lower surfaces, between proximal and distal ends, and between lateral and medial sides;   wherein the upper surface has a circumferential edge and extends upwardly relative to the circumferential edge to define first, second, third and fourth areas on the upper surface, and wherein the lower surface has at least three points defining a lower plane of reference when the device is in use;   wherein the first area extends upwardly from the proximal end toward the distal end with an average angle ranging from 8° to 10° to terminate in a first boundary, the first area and the first boundary extending transversely substantially from the lateral to the medial sides, the first boundary having a corresponding first apex located at a height selected from the range of 6 mm to 10 mm relative to the lower plane of reference, the selected height corresponding to a respective foot size of the user ranging from adult male size 8.5 to adult male size 15;   wherein the second area has a curvilinear, triangular shape with a base located at the medial side and tapering, curvilinear edges extending inwardly to a second apex, the second area extending upwardly from the medial side in a convex arc with a radius of curvature selected to range from 80 mm to 110 mm and a height ranging from 6 mm to 12 mm relative to the lower plane of reference locate the second apex at a the selected height corresponding to a respective foot size of the user ranging from adult male size 8.5 to 15;   wherein the third area has a curvilinear, triangular shape with a base located at the lateral side and tapering, curvilinear edges extending inwardly to a third apex, the third area extending upwardly from the lateral side in a convex arc to locate the third apex at a selected height ranging from 6 mm to 10 mm relative to the lower plane of reference, the selected height corresponding to a respective foot size of the user ranging from adult male size 8.5 to adult male size 15;   wherein the fourth area extends upwardly from the distal end toward the proximal end with an average angle ranging from 15° to 20° to terminate in a second boundary, the fourth area and the second boundary extending transversely substantially from the lateral to the medial sides, the fourth area having a corresponding fourth apex located at a height selected from the range of 6 mm to 10 mm relative to the lower plane of reference, the selected height corresponding to a respective foot size of the user ranging from adult male size 8.5 to adult male size 15.   
     
     
         17 . The device of  claim 16 , further comprising a plateau defined on the upper surface and sized and located to include the apices of each of the four areas. 
     
     
         18 . The device of  claim 16 , wherein the first and second boundaries comprise respective, U-shaped bevels of greater slope than respective adjacent portions of the upper surface. 
     
     
         19 . The device of  claim 18 , wherein the U-shaped bevels have respective pairs of arms extending from respective bases, and wherein the bases are located in the plateau, the pair of arms of one of the U-shaped bevels extending away from the pair of arms of the other U-shaped bevel, one of the pairs of arms extending distally to the distal end of the upper surface and the other pair of arms extending proximally toward the proximal end of the upper surface; and
 wherein the arms of the U-shaped bevels have respective heights, the heights decreasing along the arms and becoming zero at the plateau so that the bevels terminate at the plateau.