Heat malleable orthotic shoe insert

Abstract

The invention provides an orthotic insert for an article of footwear, which includes a cupped heel portion, the cupped heel portion having a concave upper bearing surface that extends above a most posterior cephalad portion of a calcaneous; and a heat-malleable mid-foot portion continuously coupled to the heel portion, the mid-foot portion having a medial longitudinal arch and a heat-deformable upper bearing surface. The invention also provides a method of treating a podiatric condition with an orthotic insert and a method of manufacturing a heat-malleable orthotic insert for an article of footwear.

What is claimed as invention is:  
     
         1 . An orthotic insert for an article of footwear, comprising: 
 a cupped heel portion, the cupped heel portion having a concave upper bearing surface that extends above a most posterior cephalad portion of a calcaneous; and    a heat-malleable mid-foot portion continuously coupled to the heel portion, the mid-foot portion having a medial longitudinal arch and a heat-deformable upper bearing surface.    
     
     
         2 . The orthotic insert of  claim 1  wherein the cupped heel portion and the mid-foot portion cooperate to invert a subtalor joint of a foot to a position of inversion and to lock a midtarsal joint of the foot during ambulation to reduce pronation and provide stabilization.  
     
     
         3 . The orthotic insert of  claim 1  wherein the concave upper bearing surface of the cupped heel portion comprises a heel-cup angle of at least 60 degrees.  
     
     
         4 . The orthotic insert of  claim 1  wherein the mid-foot portion extends from the cupped heel portion to an opposite end corresponding to an anterior end of a metatarsal bone.  
     
     
         5 . The orthotic insert of  claim 1  wherein the cupped heel portion and the mid-foot portion comprise a flexible material.  
     
     
         6 . The orthotic insert of  claim 5  wherein the flexible material is selected from the group consisting of a neoprene rubber, a silicone rubber, an elastomer, a polymeric material, a urethane, polyethylene terephthalate, a viscoelastic material, a silicone gel, and combinations thereof.  
     
     
         7 . The orthotic insert of  claim 1  wherein the heat-malleable mid-foot portion comprises a heat-malleable material.  
     
     
         8 . The orthotic insert of  claim 7  wherein the heat-malleable material comprises a material selected from the group consisting of polycaprolactone, polylactide, polyethylene terephthalate, polyglycolide, and a thermoplastic polymer.  
     
     
         9 . The orthotic insert of  claim 1  wherein the heat-deformable upper bearing surface of the mid-foot portion is plastically deformed when the orthotic insert is heated above a glass transition temperature and compressed by a foot while the orthotic insert is above the glass transition temperature.  
     
     
         10 . The orthotic insert of  claim 9  wherein the glass transition temperature is between 45 and 75 degrees centigrade.  
     
     
         11 . The orthotic insert of  claim 1  wherein the cupped heel portion and the mid-foot portion cooperate to provide a therapeutic characteristic for a podiatric condition.  
     
     
         12 . The orthotic insert of  claim 11  wherein the podiatric condition is selected from the group consisting of a heel spur, arch pain, metatarsalgia, a bunion, hammertoe, arthritis, a neuroma, diabetes foot, plantar fasciitis, cuboid syndrome, tendonitis, a stress fracture, shin splints, a pronation condition, and a foot ailment.  
     
     
         13 . The orthotic insert of  claim 1  further comprising: 
 a lower bearing surface substantially conforming to an inside surface of the article of footwear.  
 
     
     
         14 . The orthotic insert of  claim 1  further comprising: 
 a heat-malleable material in at least a portion of the cupped heel portion.  
 
     
     
         15 . The orthotic insert of  claim 1  further comprising: 
 a forefoot portion continuously coupled to the mid-foot portion, the forefoot portion extending from the mid-foot portion to a region corresponding to a distal end of a foot and from a medial side to a lateral side of the foot.  
 
     
     
         16 . The orthotic insert of  claim 15  further comprising: 
 a heat-malleable material in at least a portion of the forefoot portion.  
 
     
     
         17 . The orthotic insert of  claim 1  further comprising: 
 a thermochromatic indicator incorporated into the mid-foot portion of the orthotic insert.  
 
     
     
         18 . A method of manufacturing an orthotic insert for an article of footwear, comprising: 
 providing an orthotic insert mold with a cavity for a cupped heel portion, the cupped heel portion having a concave upper bearing surface that extends above a most posterior cephalad portion of a calcaneous; and a cavity for a heat-malleable mid-foot portion continuously coupled to the heel portion, the mid-foot portion having a medial longitudinal arch;    injecting an injection-molding compound into the orthotic insert mold;    releasing the orthotic insert from the orthotic insert mold; and    inserting a heat-malleable material into at least the mid-foot portion of the orthotic insert.    
     
     
         19 . The method of  claim 18  wherein the injection-molding compound is selected from the group consisting of a neoprene rubber, a silicone rubber, an elastomer, a polymeric material, a urethane, polyethylene terephthalate, a viscoelastic material, a silicone gel, and combinations thereof.  
     
     
         21 . The method of  claim 18  further comprising: 
 inserting a thermochromatic indicator into the mid-foot portion of the orthotic insert.  
 
     
     
         22 . A method of treating a podiatric condition, comprising: 
 providing a heat-malleable orthotic insert, the heat-malleable orthotic insert including a cupped heel portion, the cupped heel portion having a concave upper bearing surface that extends above a most posterior cephalad portion of a calcaneous; and a heat-malleable mid-foot portion continuously coupled to the heel portion, the mid-foot portion having a medial longitudinal arch and a heat-deformable upper bearing surface;    strapping a foot into a neutral position;    heating the heat-malleable orthotic insert with a heating apparatus to a temperature above a glass transition temperature of the mid-foot portion;    pressing the strapped foot into the heat-malleable orthotic insert when the mid-foot portion is above the glass transition temperature to plastically deform the heat-deformable upper bearing surface of the mid-foot portion into a shape corresponding substantially to the underside of the strapped foot; and    cooling the heat-malleable orthotic insert to a temperature below the glass transition temperature.    
     
     
         23 . The method of  claim 21  wherein the heating apparatus is selected from the group consisting of a microwave oven, a convective oven, a hot-air gun, a heating pad, a pan of heated water, and a heat-malleable orthotic insert heating unit.  
     
     
         24 . The method of  claim 21  further comprising: 
 pressing the strapped foot and the heated orthotic insert into an article of footwear when the mid-foot portion is above the glass transition temperature to plastically deform a lower bearing surface of the mid-foot portion into a shape corresponding substantially to an upper bearing surface of the article of footwear.