Pivotal brace for prosthesis

• US 5,772,619 A
• Filed: 01/31/1997
• Issued: 06/30/1998
• Est. Priority Date: 04/07/1995
• Status: Expired due to Fees

• Current Assignee: Blake Corbett
• Original Assignee: Blake Corbett
• Inventors: Corbett, Blake
• Primary Examiner(s): Dvorak, Linda C.
• Application Number:
  US08/791,546
• Time in Patent Office: 515 Days
• Field of Search: 602/5, 602/16, 602/20, 602/21, 602/23, 602/26
• US Class Current: 602/16
• CPC Class Codes: A61F 2005/0167 adjustable
• CPC Class Codes: A61F 5/0125 the device articulating around a single pivot-point

Abstract

A rotatable brace for a prothesis includes a pair of straps, each one connected to one of two wrapping supports secured on opposite sides of an ankle or wrist joint, a pivot joint including a pivot pin connecting the straps, a washer of polytetrafluoroethylene material interposed between the straps and surrounding the pivot pin and having a plurality of ports positioned radially outwardly of the pivot pin, with one end of one strap being of reduced width and having a semicircular end, shoulders joining the portion of reduced width with the main part of the strap, a number of threaded ports in the other of the straps axially aligned with respect to the ports in the washer, and a pair of screws passing through selected ports in the washer and threadedly engaged with the aligned threaded ports such that the brace can be rotated only until the shoulders abut against the heads of the screws. A hard impact of a shoulder against one of the screw heads causes a slight deflection of the screw within a port of the washer, permitting some resilience or "give" and reducing the impact against the pivot pin and the reduced width portion of the strap having the semicircular end.

Claims

1. A rotatable brace forming part of a prothesis for supporting a human joint including a first wrapping support supporting a first limb member, a second wrapping support for supporting a second limb member, said rotatable brace being secured to said wrapping supports for permitting limited rotation of said joint:

said rotatable brace comprising a first strap secured to one of said wrapping supports having a main portion and a portion of reduced width at one end terminating in a generally semicircular portion, a hole centered in said semicircular portion, and a pair of shoulder portions joining said main portion with said portion of reduced width;

a second strap secured to the other of said wrapping supports having a hole generally centered at one end thereof, and a plurality of threaded ports positioned radially outwardly of said hole;

a washer of low friction plastic material interposed between said first and second straps and having a centrally located hole and a plurality of ports aligned with said threaded ports;

a pivot pin extending through said holes in said first and second straps and through said washer; and

a pair of screws having upstanding heads extending through a pair of said ports in said washer and threadedly engaged with corresponding said threaded ports, said heads limiting rotation of said brace when contacted by said shoulder portions, said screws being deflectable and said washer being deformable to absorb forces at said rotation limit to avoid damage to said brace.

2. A rotatable brace as claimed in claim 1 wherein one of said first and second straps includes an offset portion.

3. A rotatable brace as claimed in claim 1 wherein said hole in said low friction plastic member is of larger diameter than said hole in said first strap;

a boss is formed on said first strap, said hole in said first strap extends through said boss, and said boss is positioned in said larger diameter hole.

4. A rotatable brace as claimed in claim 1 wherein said low friction plastic washer is comprises a washer of polytetrafluoroethylene material.

5. A rotatable brace for a prothesis for supporting a human joint including a first wrapping support for supporting a first limb member, a second wrapping support for supporting a second limb member, said rotatable brace being secured to said wrapping supports for permitting limited rotation of said joint:

characterized in that said rotatable brace comprises a first strap secured to one of said wrapping supports having a main portion of a desired width and a portion of reduced width at one end terminating in a generally semicircular portion, a hole generally centered in said semicircular portion, a boss surrounding said hole and a pair of shoulder portions joining said reduced width portion with said main portion;

a second strap secured to the other of said wrapping supports and having an offset portion at one end defining a pivot area, a hole generally centered in said pivot area, and a plurality of threaded ports positioned concentrically radially outwardly of said hole at a radius greater than the radius of said generally semicircular portion;

a washer of low friction plastic material surrounding said boss and interposed between said first and second straps and having a plurality of ports aligned with said threaded ports;

a pivot pin extending through said holes in said first and second straps and through said washer; and

a pair of screws having upstanding heads extending through a pair of said ports in said washer and threadedly engaged with selected pairs of said threaded ports, said heads limiting rotation of said brace when contacted by said shoulder portions, said screws being deflectable and said washer being deformable to absorb forces at said rotation limit to avoid damage to said brace.

6. A rotatable brace as claimed in claim 5 wherein said low friction threaded member comprises a washer of polytetrafluoroethylene material.

7. A rotatable brace as claimed in claim 5 wherein said screws are movable to selected pairs of said threaded ports to adjust the amount of rotation permitted by said brace.