Permanently attached artificial limb

• US 4,143,426 A
• Filed: 03/30/1977
• Issued: 03/13/1979
• Est. Priority Date: 03/30/1977
• Status: Expired due to Term

• Current Assignee: The United States of America As Represented By The Secretary of Agriculture
• Original Assignee: The United States of America As Represented By The Secretary of Agriculture
• Inventors: Mallow, William A., Hoese, Fred O., Hall, C. William
• Primary Examiner(s): Frinks, Ronald L.
• Application Number:
  US05/782,849
• Time in Patent Office: 713 Days
• Field of Search: 3/1, 3/1.9, 3/1.91, 3/2, 3/6, 3/30, 128/92 C, 128/334 R
• US Class Current: 623/53
• CPC Class Codes: A61F 2/08 Muscles; Tendons; Ligaments sutures A61B17/04
• CPC Class Codes: A61F 2/0811 Fixation devices for tendons or ligaments
• CPC Class Codes: A61F 2/2814 Bone stump caps
• CPC Class Codes: A61F 2/30749 Fixation appliances for connecting prostheses to the body
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/60 Artificial legs or feet or parts thereof
• CPC Class Codes: A61F 2002/0829 without deformation of anchor parts, e.g. fixation screws on bone surface, extending barbs, cams, butterflies, spring-loaded pins
• CPC Class Codes: A61F 2002/0864 Fixation of tendon or ligament between anchor elements, e.g. by additional screws in the anchor, anchor crimped around tendon
• CPC Class Codes: A61F 2002/087 Anchor integrated into tendons, e.g. bone blocks, integrated rings
• CPC Class Codes: A61F 2002/0888 Anchor in or on a blind hole or on the bone surface without formation of a tunnel
• CPC Class Codes: A61F 2002/307 Prostheses for animals
• CPC Class Codes: A61F 2002/30975 made of two halves
• CPC Class Codes: A61F 2002/6872 attached and mechanically operated by remaining muscle
• CPC Class Codes: A61F 2002/7887 for connecting limb exoprostheses to the stump bone
• CPC Class Codes: A61F 2250/0081 Prosthesis for animals
• CPC Class Codes: A61F 2310/00401 Coating made of iron, of stainless steel or of other Fe-based alloys
• CPC Class Codes: A61F 2310/00574 Coating or prosthesis-covering structure made of carbon, e.g. of pyrocarbon
• CPC Class Codes: A61F 2310/00928 Coating or prosthesis-covering structure made of glass or of glass-containing compounds, e.g. of bioglass
• CPC Class Codes: A61F 2310/00952 Coating, pre-coating or prosthesis-covering structure made of bone cement, e.g. pre-applied PMMA cement mantle

Abstract

A permanently attached artificial limb comprises an endoprosthesis in combination with an artificial tendon attachment. The artificial tendon attachment permits the use of existing skeletal muscles to power external articulating mechanical joints of the endoprosthesis device. The artificial tendon penetrates the skin and provides a strong interface with existing skeletal muscles.

Claims

1. An artificial tendon for forming a strong musculotendinous interface with a skeletal muscle, comprising:

a cord of high break strength forming the body of the artificial tendon;

tissue ingrowth means to promote musculotendinous attachment, having an interfacing surface with a relatively large surface area bonded to one end of said cord, said tissue ingrowth means being wrappable about the end of a skeletal muscle or tendon to form a large interface; and

a tissue ingrowth impervious backing bonded to the back non-interfacing surface of said tissue ingrowth means;

whereby a strong interface is provided for tissue ingrowth from the skeletal muscle to the large surface area of said tissue ingrowth means while said impervious backing prevents tissue ingrowth on the non-interfacing surface and prevents the artificial tendon from being thereby immobilized, so that the artificial tendon remains securely attached to the skeletal muscle while being slidable in the body with the contraction or extension of the skeletal muscle.

2. An artificial tendon as claimed in claim 1, wherein said tissue ingrowth means is a velour strip.

3. The artificial tendon of claim 2, wherein said velour strip is selected from the group consisting of nylon velour and velour fabric of fibers of polyethylene terephthalate.

4. The artificial tendon of claim 2, wherein said velour strip has dimensions of about 4 cm ×

3 cm.

5. An artificial tendon as claimed in claim 1, wherein said impervious backing is a layer of silicone.

6. An artificial tendon as claimed in claim 1, further including skin interfacing means to provide a tissue ingrowth surface of large surface area at the skin interface, whereby when the artificial tendon is used to attach an external articulating joint of an endoprosthesis to a skeletal muscle, the artificial tendon penetrates through the skin and the skin interfacing means provides a strong interface under external dynamic loading of the artificial tendon.

7. An artificial tendon as claimed in claim 6, wherein said skin interfacing means comprises a velour covered silicone ball formed in said cord near the end to which said tissue ingrowth means are attached, whereby said ball provides a large tissue ingrowth surface at the skin interface.

8. The artificial tendon of claim 7, wherein said ball is about 1 cm in diameter.

9. An artificial limb adapted to become permanently attached, comprising:

an endoprosthesis with an external articulating joint; and

an artificial tendon adapted to connect said external articulating joint to a skeletal muscle with said tendon passing through the skin, said artificial tendon comprising skin interfacing means to provide a tissue ingrowth surface of large surface area at the skin interface, and tissue interfacing means for musculotendenous attachment including a large surface area wrappable about the end of a skeletal muscle or tendon to form a large interface.

10. An artificial limb adapted to become permanently attached, comprising:

a supracortical endoprosthesis with an external articulating joint; and

an artificial tendon adapted to connect said external articulating joint to a skeletal muscle with said tendon passing through the skin, said artificial tendon comprising skin interfacing means to provide a tissue ingrowth surface of large surface area at the skin interface.

11. An artificial limb as claimed in claim 10, wherein said supracortical endoprosthesis comprises:

a collet to grip the distal end of the bone;

a forcing cone fitting over said collet; and

an external jam nut which can be tightened to drive said forcing cone over said collet.

12. An artificial limb as claimed in claim 11, wherein the inner surface of said collet is coated with a material conducive to bone ingrowth, whereby a direct bone interface is achieved.

13. An artificial limb as claimed in claim 11, wherein said collet is tapered.

14. An artificial limb as claimed in claim 11, wherein said collet is a split collet.

15. An artificial limb as claimed in claim 11, wherein the outer surface of said forcing cone is coated with a bonded layer of nylon velour to provide tissue ingrowth at the skin interface.

16. An artificial limb adapted to become permanently attached, comprising:

a supraperiosteal endoprosthesis with an external articulating joint; and

an artificial tendon adapted to connect said external articulating joint to a skeletal muscle with said tendon passing through the skin, said artificial tendon comprising skin interfacing means to provide a tissue ingrowth surface of large surface area at the skin interface.

17. An artificial limb as claimed in claim 16, wherein said supraperiosteal endoprosthesis comprises:

a collet;

a forcing cone fitting over said collet;

an external jam nut which can be tightened to drive said forcing cone over said collet;

a precast elastomer held within said collet, said precast elastomer having a channel to grip the bone; and

a velour lining on said channel of said precast elastomer whereby said precast elastomer with said velour lining is pressed against the bone by driving said forcing cone over said collet, whereby a soft tissue interface is achieved with the periosteum covering the bone.

18. An artificial limb is claimed in claim 17, wherein said collet and said forcing cone have parallel sides.