Microminiature chainmail interface between skin and a transcutaneous prosthetic device and a method of manufacture

Patent metadata

Field	Value
Publication number	US-2016199201-A1
Application number	US-201614996040-A
Country	US
Kind code	A1
Filing date	Jan 14, 2016
Priority date	Jan 14, 2015
Publication date	Jul 14, 2016
Grant date	—

Abstract

The disclosure describes a direct skeletal attachment (DSA) device including a micro-miniature chainmail skin-to-DSA interface. The interface comprises various porous architectures for skin ingrowth and integration as barriers against pathogens. Failure of skin-to-DSA interfaces can occur due to mismatches in mechanical compliance between pliable skin and more rigid DSA interfaces. To address this problem, in embodiments disclosed herein is an interface having a gradient in mechanical compliance or link mobility, ranging from fully flexible, to less compliant, to rigid where it attaches to the main DSA body.

First claim

What is claimed is:

1 . A direct skeletal attachment device comprising:
an intramedullary stem adapted to be inserted into a cavity of a bone; a post adapted to interface with a prosthesis; an interface positioned between the post and stem,
wherein the interface extends radially from a first end proximate the post and stem to a second end;
wherein the interface is rigid at the first end.

2 . The direct skeletal attachment of claim 1 , wherein the interface comprises:
a series of interconnected links, wherein the interconnected links form a chainmail scaffolding.

3 . The direct skeletal attachment of claim 2 , wherein an inner diameter of each link of the series of interconnected links increases from the first end to the second end.

4 . The direct skeletal attachment of claim 2 , wherein a thickness of each link of the series of interconnected links decreases from the first end to the second end.

5 . The direct skeletal attachment of claim 2 , wherein the chainmail scaffolding has a porosity gradient.

6 . The direct skeletal attachment of claim 1 , wherein the chainmail is fully dense near the stem and the post.

7 . The direct skeletal attachment of claim 5 , a plurality of pores remain above a minimum pore diameter within the porosity gradient.

8 . The direct skeletal attachment of claim 1 , wherein the interface tapers from mechanically compliant at the second end to rigid at the first end.

9 . The direct skeletal attachment of claim 2 , wherein the links are mobile at the second end and are immobile at the second end.

10 . A method of manufacturing a micro-miniature chainmail based on a model, the method comprising:
building a first row of links using an additive manufacturing process; building a second row of links on the first row links using the additive manufacturing process, wherein the first row of links and the second row of links are rigidly attached; building subsequent rows of links using the additive manufacturing process, wherein each subsequent row is rigidly attached to a previously constructed row of links,
wherein the first row of links, the second row of links, and the subsequent row of links are based on the model;
etching the links to remove the rigid attachment between adjacent links.

11 . The method of claim 10 , wherein the additive manufacturing process is direct metal laser sintering.

12 . The method of claim 10 , wherein dimensions of the chainmail in the model are larger than desired dimensions.

13 . The method of claim 12 , wherein etching the links comprises:
submerging the links in an etchant; and removing the links when the links reach the desired dimensions.

14 . The method of claim 12 , wherein etching the links comprises:
submerging only a portion of the links in an etchant to create a gradient in dimensions of the links.

15 . The method of claim 10 , wherein the first row of links and the second row of links are rigidly attached by a support structure.

16 . A chainmail created by the method of claim 10 .

17 . A chainmail created by the method of claim 15 .

Assignees

• Univ Carnegie Mellon

Inventors

• Weiss Lee E
• Fedder Gary K

Classifications

• B22F10/40

  Structures for supporting workpieces or articles during manufacture and removed afterwards · CPC title

• B22F10/62

  by chemical means · CPC title

• B22F10/28

  Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM] · CPC title

• A61F2002/7887

  for connecting limb exoprostheses to the stump bone · CPC title

• A61F2/5046

  for designing or making customized prostheses, e.g. using templates, finite-element analysis or CAD-CAM techniques · CPC title