A process for manufacturing insoles from flexible, porous and stickable sheet plastic material by sheering the sheet to form a peripheral cut of the insole and an internal cut in the heel area to form an open area surrounded by a land area. The insole is then placed in a mold die and plastic is injected to fill in the open area and surround the land area to conform to a predetermined contour. The insole is stabilized in the die by a plurality of rods positioned within the die.

An insole and outsole construction is provided which is particularly applicable to athletic shoes, but which has general utility in a wide variety of boots and shoes. The insole construction includes three pads formed on its upper surface for engaging the bottom of the foot and which will be designated herein as the tri-plane heel pad, the lateral heel pad and the buttress pad. The outsole construction includes the provision of inserts of relatively dense material directly under the lateral and tri-plane pads. The pads and inserts cooperate to provide adequate stability, particularly to the foot and ankle during violent movements thereof; and to minimize movement of the foot within the shoe, thereby to cut down to a large extent generation of frictional heat. The insole pads also serve to minimize foot elongation and thereby decrease movement of the forefoot and thereby prevent injury to the toes. The outsole inserts tend to inhibit the tendency of the shoe to turn violently with resulting injury during strenuous athletic exercise. The insole pads also serve to stabilize the foot in the shoe with a minimum of muscle activity, resulting in minimizing fatigue.

A method of making an insole having a heel positioner and an arch support, in which the positioning support for the heel is made in situ, in one discrete section of the foot support, and the arch support is then made, in situ, in a second discrete section. The first discrete section is made at the heel portion of the foot, in a manner so as to stabilize the plantar surface of the heel section of the foot under the cancaneous bone. This is for the purpose of eliminating, reducing or minimizing the rotation forces applied to the heel section of the foot by the weight of the body, which would normally tend to produce a pes valgus (outward bending) or a pes varus (inward bending) condition, as well as stabilizing the anterior - posterior position of the leg in its function of bearing body weight. Once the heel stabilizer section has been formed, in situ, a discrete arch support section is then provided, in situ, for the arch portions of the foot so that the body weight will not tend to place strain upon the inner structures of the foot (bone joints, tendons, muscles, and related tissues), in the arch sections which connect the heel to the second part of the foot that support the body weight (i.e., the ball of the foot).

An orthotic device which includes a resilient member having a perimetral outline conforming to a predetermined portion of the human foot. This resilient member includes a plurality of segments, each of these segments having a perimetral outline conforming to a predetermined different portion of the human foot. All of the segments are of the same uniform thickness. The durometer of the segments are selected from one of a group of ranges of durometer 120 BHN or less, 140 BHN, and 180 BHN and greater.

The removable insole for shoes consists of a thin strip (1) of plastic foam, such as polyolefin foam, in the general shape of the foot. This strip (1) has grooves (6, 7, 8) which are located at the edge of the insole or delimiting zones (3, 4, 5) on the insole which are of different thicknesses, and thus of different densities. The edge of the insole is bevelled (9, 10). The insole (1) gradually becomes permanently deformed on contact with the foot and finally adopts the profile thereof. The grooves (6, 7, 8) allow the insole to change shape more easily.