Joint prosthesis

Claim 2

A prosthesis for replacement of a skeletal hinged joint, comprising: first and second stems each adapted to be inserted into a medullary canal of a bone of said joint, and a flexing web integral with said stems, joining said stems and acting as a hinge to enable the first and second stems to swing relatively to each other, said stems lying in a common plane and inclined to each other to make an included angle, with said web at the vertix, which in its at-rest non-flexed position is between 90* and 160*, each said stem and said web having a reinforcing core and a cushioning coating of elastomer, each said stem but not said web also having an outer layer with an open-pore three-dimensional reticular structure adapted to receive host tissue ingrowth, said core being continuous through said stems and web and comprising a series of longitudinally extending cords which at said web are coplanar to increase lateral stability.

Claim 3

A prosthesis for replacement of a skeletal hinged joint, comprising: first and second stems each adapted to be inserted into a medullary canal of a bone of said joint, and a flexing web integral with said stems, joining said stems and acting as a hinge to enable the first and second stems to swing relatively to each other, said stems lying in a common plane and inclined to each other to make an included angle, with said web at the vertix, which in its at-rest non-flexed position is between 90* and 160*, each said stem and said web having a reinforcing core and a cushioning coating of elastomer, each said stem but not said web also having an outer layer with an open-pore three-dimensional reticular structure adapted to receive host tissue ingrowth, said core being continuous through said stems and web and comprising a series of longitudinally extending cords which at said web are coplanar to increase lateral stability.

Claim 4

A prosthesis for replacement of a skeletal hinged joint, comprising: first and second stems each adapted to be inserted into a medullary canal of a bone of said joint, and a flexing web integral with said stems, joining said stems and acting as a hinge to enable the first and second stems to swing relatively to each other, said stems lying in a common plane and inclined to each other to make an included angle, with said web at the vertix, which in its at-rest non-flexed position is between 90* and 160*, each said stem and said web having a reinforcing core and a cushioning coating of elastomer, each said stem but not said web also having an outer layer with an open-pore three-dimensional reticular structure adapted to receive host tissue ingrowth, said core being continuous through said stems and web and comprising a series of longitudinally extending cords which at said web are coplanar to increase lateral stability.

Claim 5

The prosthesis of claim 1 wherein said coating of elastomer contains fibers and is bonded to and at least partially encloses said core.

Claim 6

The prosthesis of claim 1 for use in an elbow wherein said included angle lies between about 100* and 120*.

Claim 7

The prosthesis of claim 1 for use in finger joints wherein said included angle lies between about 130* and 160*.

Claim 8

The prosthesis of claim 1 wherein said cords are spaced apart at said web and are gathered together at said stems.

Claim 9

The prosthesis of claim 5 wherein said cords are twisted together at said stems.

Claim 10

The prosthesis of claim 1 having in addition a rigid reinforcing member in at least one of said stems.

Claim 11

The prosthesis of claim 1 wherein cords extend out through at least one of said stems to provide sutures for installation.

Claim 12

The prosthesis of claim 1 having sutures binding said core, uticular structure and elastomer together.

Claim 13

The prosthesis of claim 1 for use in an elbow wherein said first stem has a flattened conical shape for fitting into the medullary canal of an ulna.

Claim 14

The prosthesis of claim 10 wherein said second stem has a stabilizing portion with keyed exterior shape disposed perpendicularly to the plane of said web at the base of said second stem for fitting into key notches provided in a humerus.

Claim 15

The elbow prosthesis of claim 11 wherein said keyed exterior shape is triangular in cross section.

Claim 16

The elbow prosthesis of claim 11 wherein said keyed exterior shape comprises rounded rectangular buttresses.

Claim 17

The prosthesis of claim 1 wherein said web is large in width and thin in thickness to restrict the relative swinging motion of said stems along a single plane.

Claim 18

The prosthesis of claim 14 wherein said web is wider than said stems and thinner than them.

Claim 19

The prosthesis of claim 1 wherein said core further includes two separate rigid members, one for each said stem, neither said rigid member extending through said web.

Claim 20

The prosthesis of claim 16 wherein said rigid members are metal.

Claim 21

The prosthesis of claim 1 wherein said web has a thin central portion between two thicker portions and an inverted tee slot overlying said thin portion between said thicker portions on one face of said thin portion for distributing bending forces over a substantial area of said thin portion.

Claim 22

The prosthesis of claim 18 wherein said thin portion has, on the surface opposite from said slot, a curved surface thinnest at the middle and thicker nearer said stems.

Claim 23

A prosthesis for replacement of a skeletal hinged joint, comprising: a unitary member having a central hinge portion and a stem connected at each end of said hinge portion, each said stem having a base and adapted for insertion into a medullary canal of a bone of the joint, said hinge portion having a thin central web portion and thicker end portions where they join said stems providing uniplanar hinge-like movement about said web portion when said stems are implanted in said canals, said stems being inclined with respect to said web portion to provide an included angle of at least 90* and no more than about 160* when said web portion is in an unflexed condition, said unitary member being made of elastomer and having internal reinforcing means extending through said hinge portion and said stems, said stems having an open-pore, three-dimensional, reticular outer layer for three-dimensional tissue ingrowth, said reinforcing means comprising a series of longitudinally extending cords which at said web portion are coplanar to increase lateral stability.

Claim 24

A prosthesis for replacement of a skeletal hinged joint, comprising: a unitary member having a central hinge portion and a stem connected at each end of said hinge portion, each said stem having a base and adapted for insertion into a medullary canal of a bone of the joint, said hinge portion having a thin central web portion and thicker end portions where they join said stems providing uniplanar hinge-like movement about said web portion when said stems are implanted in said canals, said stems being inclined with respect to said web portion to provide an included angle of at least 90* and no more than about 160* when said web portion is in an unflexed condition, said unitary member being made of elastomer and having internal reinforcing means extending through said hinge portion and said stems, said stems having an open-pore, three-dimensional, reticular outer layer for three-dimensional tissue ingrowth, said reinforcing means comprising a series of longitudinally extending cords which at said web portion are coplanar to increase lateral stability.

Claim 25

The prosthesis of claim 20 wherein said reinforcing means occupies substantially all the interior space of said stems.

Claim 26

A prosthesis as in claim 20 for use in an elbow wherein said included angle lies between 100* and 120*.

Claim 27

A prosthesis as in claim 20 for use in finger joints wherein said included angle lies between 130* and 160*.

Claim 28

A prosthesis as in claim 20 including suturing means at said base of at least one said stem.

Claim 29

A prosthesis as in claim 20 wherein said base of at least one of said stems has a stabilizing buttress shaped to fit into a notch proVided in the resected head of said bone of the joint and disposed perpendicularly to the plane of said hinge portion.

Claim 30

The prosthesis of claim 20 wherein said reinforcement is cords gathered into a generally cylindrical configuration in each said stem.

Claim 31

The prosthesis of claim 26 wherein said cords are secured to each other by stitches.

Claim 32

A prosthesis as in claim 20 wherein said cords are braided.

Claim 33

A prosthesis as in claim 20 wherein said internal reinforcing means further includes a rigid core member embedded within at least one of said stems as well as a portion of said end portion adjacent said stem but not extending into said web.

Claim 34

A prosthesis for replacement of a skeletal hinged joint, comprising: a unitary member having a central hinge portion and a stem connected at each end of said hinge portion, each said stem having a base and adapted for insertion into a medullary canal of a bone of the joint, said hinge portion having a thin central web portion and thicker end portions where they join said stems providing uniplanar hinge-like movement about said web portion when said stems are implanted in said canals, said stems being inclined with respect to said web portion to provide an included angle of at least 90* and no more than about 160* when said web portion is in an unflexed condition, said unitary member being made of elastomer and having internal reinforcing means extending through said hinge portion and said stems, to increase lateral stability, said stems having an open-pore, three-dimensional reticular outer layer for three-dimensional tissue ingrowth, said reinforcing means including a plurality of fibers extending longitudinally and continuously through said member, and a rigid core member embedded within at least one of said stems as well as a portion of said end portion adjacent said stem but not extending into said web, said prosthesis further including a stabilizing cuff member secured at said base of said stem containing said rigid core member and extending outwardly therefrom to surround loosely at least a portion of said stem, said cuff member having an open-pore inner surface adapted for ingrowth of tissue, said cuff member being adapted for encirclement of the exterior of the bone in which its associated said stem is inserted.

Claim 35

A prosthesis for replacement of a skeletal hinged joint, comprising: a unitary member having a central hinge portion and a stem connected at each end of said hinge portion, each said stem having a base and adapted for insertion into a medullary canal of a bone of the joint, said hinge portion having a thin central web portion and thicker end portions where they join said stems providing uniplanar hinge-like movement about said web portion when said stems are implanted in said canals, said stems being inclined with respect to said web portion to provide an included angle of at least 90* and no more than about 160* when said web portion is in an unflexed condition, said unitary member being made of elastomer and having internal reinforcing means extending through said hinge portion and said stems, to increase lateral stability, said stems having an open-pore, three-dimensional reticular outer layer for three-dimensional tissue ingrowth, said reinforcing means including a plurality of fibers extending longitudinally and continuously through said member, and a rigid core member embedded within at least one of said stems as well as a portion of said end portion adjacent said stem but not extending into said web, said prosthesis further including a stabilizing cuff member secured at said base of said stem containing said rigid core member and extending outwardly therefrom to surround loosely at least a portion of said stem, said cuff member having an open-pore inner surface adapted for ingrowth of tissue, said cuff member being adapted for encirclement of the exterior of the bone in which its associated said stem is inserted.

Claim 36

A prosthesis as in claim 30 further including suturing means secured at said base of the other said stem and in an outer portion of said cuff member.

Claim 37

A prosthesis for replacement of a skeletal hinge joint, comprising: a unitary member having a central hinge portion and a stem connected at each end of said hinge portion, each said stem having a base and adapted for insertion into a medullary canal of a bone of the joint, said hinge portion having a thin central web portion and thicker end portions where they join said stems providing uniplanar hinge-like movement about said web portion when said stems are implanted in said canals, said stems being inclined with respect to said web portion to provide an included angle of at least 90* and no more than about 160* when said web portion is in an unflexed condition, said unitary member being made of elastomer and having internal reinforcing means extending through said hinge portion and said stems, to increase lateral stability, said stems having an open-pore, three-dimensional, reticular outer layer for three-dimensional tissue ingrowth, said prosthesis further including a stabilizing cuff member secured at said base of one of said stems and extending outwardly therefrom and loosely around at least a portion of said stem, said cuff member having an open-pore inner surface adapted for ingrowth of tissue, said cuff member being adapted for encirclement of the exterior of the bone in which its associated said stem is inserted.

Claim 38

A prosthesis for replacement of a skeletal hinge joint, comprising: a unitary member having a central hinge portion and a stem connected at each end of said hinge portion, each said stem having a base and adapted for insertion into a medullary canal of a bone of the joint, said hinge portion having a thin central web portion and thicker end portions where they join said stems providing uniplanar hinge-like movement about said web portion when said stems are implanted in said canals, said stems being inclined with respect to said web portion to provide an included angle of at least 90* and no more than about 160* when said web portion is in an unflexed condition, said unitary member being made of elastomer and having internal reinforcing means extending through said hinge portion and said stems, to increase lateral stability, said stems having an open-pore, three-dimensional, reticular outer layer for three-dimensional tissue ingrowth, said prosthesis further including a stabilizing cuff member secured at said base of one of said stems and extending outwardly therefrom and loosely around at least a portion of said stem, said cuff member having an open-pore inner surface adapted for ingrowth of tissue, said cuff member being adapted for encirclement of the exterior of the bone in which its associated said stem is inserted.

Claim 39

A prosthesis as in claim 32 further including suturing means secured at said base of the other said stem anD in an outer portion of said cuff member.

Claim 40

A prosthesis for replacement of a damaged or diseased elbow joint, comprising: a unitary, elastomeric member having a central hinge portion thicker at each end and thinner in its central web portion with a first stem joined to one said end and second stem joined to the other said end, each said stem having a base portion, said member having internal fiber reinforcement substantially throughout and an open-pore, tridimensional, reticular layer on the outer surface of said first and second stems, and a cuff member encircling said base of said first stem and extending outwardly therefrom to surround at least a portion of said first stem, said cuff member having an open-pore inner surface adapted for ingrowth of tissue.

Claim 41

A prosthesis for replacement of a damaged or diseased elbow joint, comprising: a unitary, elastomeric member having a central hinge portion thicker at each end and thinner in its central web portion with a first stem joined to one said end and second stem joined to the other said end, each said stem having a base portion, said member having internal fiber reinforcement substantially throughout and an open-pore, tridimensional, reticular layer on the outer surface of said first and second stems, and a cuff member encircling said base of said first stem and extending outwardly therefrom to surround at least a portion of said first stem, said cuff member having an open-pore inner surface adapted for ingrowth of tissue.

Claim 42

The prosthesis of claim 34 wherein said first and second stems are inclined with respect to said web portion to provide an included angle of at least 90* and no more than 160* when said web portion is in an unflexed condition.

Claim 43

A prosthesis of claim 34 further including a rigid core member embedded within said first stem and a portion of said end of said hinge portion to which said first stem is joined.

Claim 44

A prosthesis of claim 34 wherein said reinforcement comprises a multiplicity of longitudinally arranged fibers.