MODULAR PROSTHETIC SOCKET
A flexible distal cup for use as part of a modular prosthetic socket for a residual limb may have a substantially closed distal end, an open proximal end, an inner surface and an outer surface. The flexible distal cup is configured to reside within an outer support structure of the prosthetic socket and to receive a distal portion of the residual limb. In some embodiments, the flexible distal cup may be made of a composite polymer composition, including an ethylene-vinyl acetate (EVA) copolymer and polycaprolactone (PCL). The EVA copolymer may be between about 45% and about 55% of the composite polymer composition by weight, the vinyl acetate of the EVA copolymer may be less than about 25% of the EVA copolymer by weight, and the PCL may be between about 45% and about 55% of the composite polymer composition by weight.
1 . A device for use as part of a modular prosthetic socket for a residual limb, the device comprising:
a flexible distal cup comprising a substantially closed distal end, an open proximal end, an inner surface and an outer surface, wherein the flexible distal cup is configured to reside within an outer support structure of the prosthetic socket and to receive a distal portion of the residual limb,
wherein the flexible distal cup comprises a composite polymer composition, comprising an ethylene-vinyl acetate (EVA) copolymer and polycaprolactone (PCL),
wherein the EVA copolymer comprises between about 45% and about 55% of the composite polymer composition by weight,
wherein vinyl acetate of the EVA copolymer comprises less than about 25% of the EVA copolymer by weight,
wherein the PCL comprises between about 45% and about 55% of the composite polymer composition by weight, and
wherein the composite polymer composition has a reformable temperature of between about 125° F. and about 160° F., and a flexural modulus of about 3,500.
2 . The device of claim 1 , further comprising an anchoring insert attached to the distal end of the flexible distal cup.
3 . The device of claim 2 , wherein the anchoring insert comprises:
an inner concentric zone attached to the inner surface of the flexible distal cup at the distal end; and
an outer concentric zone attached to the outer surface of the flexible distal cup at the distal end.
4 . The device of claim 2 , wherein the anchoring insert comprises a 1-way valve configured to allow air to escape from an internal space within the flexible distal cup to an external environment.
5 . The device of claim 2 , wherein the anchoring insert comprises a 2-way valve configured to allow air to travel in either direction between an internal space within the flexible distal cup and an external environment.
6 . The device of claim 1 , wherein the flexible distal cup is provided in an inventory of devices, wherein devices within the inventory comprise variation in at least one of length or circumference.
7 . The device of claim 1 , wherein the flexible distal cup is provided in an inventory of devices, wherein devices within the inventory comprise variation in shape to conform to a residual limb having a shape selected from the group consisting of a conical shape, a tubular shape, and a bulbous shape.
8 . The device of claim 1 , wherein the flexible distal cup has a length approximately equal to a length of the prosthetic socket.
9 . The device of claim 1 , wherein flexible distal cup has a length less than a length of the prosthetic socket.
10 . The device of claim 1 , wherein the flexible distal cup is sufficiently flexible to conform to the distal portion of the residual limb.
11 . The device of claim 1 , wherein the flexible distal cup is sufficiently elastic to conform to the distal portion of the residual limb.
12 . A method of making a flexible distal cup for a modular prosthetic socket for a residual limb, the method comprising:
compounding ethylene-vinyl acetate (EVA) copolymer pellets and polycaprolactone (PCL) pellets to generate a composite polymer composition, wherein the EVA copolymer comprises between about 45% and about 55% of the composite polymer composition by weight, wherein vinyl acetate comprises less than 25% of the EVA copolymer by weight, and wherein the PCL comprises between about 45% and about 55% of the composite polymer composition by weight; and
forming the flexible distal cup from the composite polymer composition into an initial form.
13 . The method of claim 12 , wherein compounding comprises at least one of heating, mixing, or applying pressure to the EVA copolymer pellets and the PCL pellets.
14 . The method of claim 12 , further comprising thermally reforming the initial form of the flexible distal cup, thermally reforming comprising:
providing the flexible distal cup in the initial form;
heating the flexible distal cup in its initial form to a sufficient temperature and for a sufficient duration to render the composite polymer composition of the flexible distal cup pliable; and
applying sufficient force to the flexible distal cup in its initial form to change a the shape of the flexible distal cup from the initial form to a final form.
15 . The method of claim 14 , wherein heating the flexible distal cup comprises placing the flexible distal cup in a bath.
16 . The method of claim 14 , wherein applying sufficient force comprises applying the flexible distal cup to a distal portion of the residual limb.
17 . The method of claim 16 , further comprising, before applying the flexible distal cup to the distal portion of the residual limb, wrapping the distal portion of the residual limb in a thermally insulating fabric.
18 . The method of claim 16 , wherein the final form of the flexible distal cup substantially conforms to the distal portion of the residual limb.
19 . The method of claim 17 , wherein the final form of the flexible distal cup encompasses a volume that is greater than that of the initial form of the distal cup.