Joint prosthesis having PTFE cushion
OwnerD. Kenneth Walston, Lawrence M. Haasinventors
Life of this patent
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Abstract
A joint prosthesis for interconnecting the ends of adjoining bones includes a cushion of expanded PTFE having at least two facets for attachment to the bones. The cushion may or may not include stems for insertion into the bones. An optional sheath surrounds the non-facet surfaces of the cushion for preventing adherence of tissue. The motion of the prosthesis is defined or limited by the orientation of the facets and/or by the porosity of the cushion and/or by an insert within the cushion.
Claims22
A joint prosthesis for replacing a natural joint between a first bone and a second bone which can move relative to the first bone, said prosthesis imitating the motion of the natural joint by interconnecting the adjoining ends of said first bone and said second bone, said prosthesis comprising:
- a cushion of expanded polytetrafluoroethylene having a first facet for attachment to said first bone and a second facet for attachment to said second bone;
- wherein said cushion permits a bi-axial motion between said facets and a sideward motion in response to shear forces on said facets.
A joint prosthesis for interconnecting the adjoining ends of a first bone and a second bone, said prosthesis comprising:
- a cushion of expanded polytetrafluoroethylene;
- a sheath partially surrounding said cushion, said sheath having a first open end and a second open end;
- wherein said cushion is adapted to be attached to said first bone through said first open end and said cushion is adapted to be attached to said second bone through said second open end.
A joint prosthesis for interconnecting the adjoining ends of metacarpophalangeal bones, said prosthesis comprising:
- a cushion of expanded polytetrafluoroethylene having a first facet adapted to be connected to a first metacarpophalangeal bone and a second facet adapted to be connected to a second metacarpophalangeal bone;
- wherein said cushion is more porous at said facets than between said facets for promoting ingrowth of the metacarpophalangeal bone.
A joint prosthesis for replacing a natural joint between a first bone and a second bone which can move relative to the first bone, said prosthesis imitating the motion of the natural joint by interconnecting the adjoining ends of said first bone and said second bone, said prosthesis comprising:
- a cushion of expanded polytetrafluoroethylene having a first facet for attachment to said first bone and a second facet for attachment to said second bone;
- a first stem attached to and extending from said first facet;
- and
- a second stem attached to and extending from said second facet;
- wherein said cushion permits at least bi-axial motion between said facets and a sideward motion in response to shear forces on said facets, said prosthesis further comprising:
- an insert within said cushion for limiting the motion of said cushion along an axis.
A joint prosthesis for replacing a natural joint between a first bone and a bone which can move relative to the first bone, said prosthesis imitating the motion of the natural joint by interconnecting the adjoining ends of said first bone and said second bone, said prosthesis comprising:
- a cushion of expanded polytetrafluoroethylene having a first facet for attachment to said first bone and a second facet for attachment to said second bone;
- a first stem attached to and extending from said first facet;
- and
- a second stem attached to and extending from said second facet;
- and
- a sheath surrounding at least a portion of said cushion.
Dependencies are inferred from the claim text.