Custom-molded liner for artificial limb socket

• US 5,888,231 A
• Filed: 10/08/1997
• Issued: 03/30/1999
• Est. Priority Date: 10/08/1997
• Status: Expired due to Term

• Current Assignee: 3M Company
• Original Assignee: 3M Company
• Inventors: Anderson, Richard E., McGurran, Kelly T., Sandvig, Timothy C.
• Primary Examiner(s): Willse, David H.
• Application Number:
  US08/947,172
• Time in Patent Office: 538 Days
• Field of Search: 602/8, 602/62, 602/63, 623/36, 623/33-37, 264/222, 264/DIG. 30, 425/2
• US Class Current: 623/36
• CPC Class Codes: A61F 2/7812 Interface cushioning members placed between the limb stump and the socket, e.g. bandages or stockings for the limb stump
• CPC Class Codes: A61F 2/80 Sockets, e.g. of suction type
• CPC Class Codes: A61F 2002/5053 using a positive or a negative model, e.g. casting model or mould
• CPC Class Codes: A61F 2002/607 Lower legs
• CPC Class Codes: A61F 2002/7818 Stockings or socks for the limb stump cosmetic coverings A61F2002/5001
• CPC Class Codes: Y10S 623/901 Method of manufacturing prosthetic device

Abstract

A method of preparing a breathable, custom-molded liner for an artificial limb socket includes the steps of providing a liner comprising an open-celled foam material impregnated with a curable resin, activating the curable resin, and deforming the foam material by positioning a residual limb on one of opposing surfaces of the liner, and positioning the artificial limb socket on a second opposing surface of the liner until curing is substantially complete to create and retain an impression of the residual limb in the foam material. A liner blank useful for preparing an artificial limb socket, comprising a foam material impregnated with a curable resin and sewn into the shape of a sock for an artificial limb, is also described.

Claims

1. A method of preparing a breathable, custom-molded liner for an artificial limb socket, comprising the steps of:

providing a liner blank having opposing surfaces, the liner comprising an open-celled foam material impregnated with a curable resin;

activating the curable resin; and

deforming the foam material by positioning a residual limb on one of the opposing surfaces and positioning the artificial limb socket on the second of the opposing surfaces until curing is substantially complete to create and retain an impression of the residual limb and the limb socket in the foam material, wherein the artificial limb socket comprises a plurality of apertures such that a composite comprising the socket and the cured foam material is breathable.

2. The method of claim 1, wherein the liner blank comprises an open-celled foam sheet adjacent a breathable cover material.

3. The method of claim 2, wherein the breathable cover material comprises an extensible fabric.

4. The method of claim 3, wherein the extensible fabric comprises a knitted fiberglass.

5. The method of claim 1, wherein the curable resin comprises an isocyanate functional, prepolymer resin, the prepolymer resin being formed by reacting a polyisocyanate with a polyol wherein the ratio of NCO groups in the polyisocyanate to OH groups in the polyol is between about 2 to 1 and about 5 to 1, the prepolymer resin having an NCO equivalent weight of from about 275 to about 1000 grams of prepolymer resin per NCO group.

6. The method of claim 5, wherein the ratio of NCO groups in the polyisocyanate to OH groups in the polyol is between about 2.5 to 1 and about 4 to 1.

7. The method of claim 5, wherein the prepolymer resin has an NCO equivalent weight of from about 350 to about 700 grams of prepolymer resin per NCO group.

8. The methods of claim 5, wherein the prepolymer resin is formed by reacting the polyisocyanate with the polyol while the polyisocyanate and the polyol are inside the foam material.

9. The method of claim 1, wherein the open-celled foam material contains from about 12 to about 48 pores per centimeter.

10. The method of claim 1, wherein the open-celled foam material has a density of less than about 349 kg/m³.

11. The method of claim 10, wherein the open-celled foam material has a density of between about 20 kg/m³ and about 40 kg/m³.

12. The method of claim 5, wherein the prepolymer resin comprises between about 70% and about 95% by weight of the foam material.

13. The method of claim 12, wherein the prepolymer resin comprises from about 80% to about 90% by weight of the foam material.

14. The method of claim 1, wherein the liner blank is in the form of a sock adapted to be placed over a residual limb and adapted to be received in an artificial limb socket.