Prosthetic joint for total knee replacement

Claim 2

A joint prosthesis comprising, first prosthetic means for fixation to a first skeleton element and including a convexly shaped articulation surface for location at the distal end of said first skeleton element, second prosthetic means for fixation to a second skeleton element adjacent said first skeleton element and including a concavely shaped articulation surface for location at the proximal end of said second skeleton element, and link means pivotally connected to said first and second prosthetic means to provide slidable and rotational contact between said convexly shaped and said concavely shaped articulation surfaces, said link means being pivotally connected to said first prosthetic means by a ball and socket and pivotally connected to said second prosthetic means by a pin.

Claim 3

The joint prosthesis according to claim 1 wherein said link means is arranged to have said first prosthetic means pivot about said pin during a first instance of motion and pivot about said ball and socket during a second instance of motion.

Claim 4

The joint prosthesis according to claim 1 wherein said first prosthetic means has a head portion having a pair of spaced apart involute shaped surfaces forming said convexly shaped articulation surface, a slot formed between said pair of spaced apart involute shaped surfaces, a socket communicating with said slot, said second prosthetic means has a head portion including insert elements forming said concavely shaped articulation surface, said insert elements providing spaced apart engagement surfaces in contact with said pair of involute shaped surfaces, said link means being a ball stud pinned to said second prosthetic means for limited pivotal movement and extending into the ball socket of said first prostheTic means through said slot, and a ball secured to said ball stud and positioned within said socket, whereby said first and second prosthetic means move relative to one another by rotational and sliding action between said engagement surfaces and said involute shaped surfaces.

Claim 5

The joint prosthesis according to claim 3 wherein said ball on said ball stud is axially movable during movement between said first and second prosthetic means.

Claim 6

The joint prosthesis according to claim 3, wherein a stop member extends from said second prosthetic means into said slot formed in said first prosthetic means, said stop member engageable with a front wall of said slot to limit forward bending between said first and second prosthetic means.

Claim 7

The joint prosthesis according to claim 1 wherein said first and second prosthetic means each includes stem members extending therefrom to be inserted into the skeleton element receiving the same, and said stem members have rough peripheral surface about said stem members and extending a given distance along said stem members.

Claim 8

An applicance for replacement of a disabled human joint comprising: first prosthetic means including a stem member adapted for fixation in a first skeleton element and further including a first joint-forming member at one end of said stem member, said first joint-forming member having a convexly shaped articulation surface; second prosthetic means including a second stem member adapted for fixation in a second skeleton element disposed adjacent said first skeleton element and further including a second joint-forming member at one end of said second prosthetic means, said second joint-forming member having a concavely shaped articulation surface engageable with said convexly shaped articulation surface; link means cooperating to couple said first and second prosthetic means so that said convexly shaped articulation surface and said concavely shaped articulation surface are in slidable rotational contact with one another; and pivot means connecting one end of said link means to at least one of said prosthetic means, said pivot means includes a pin for connecting said link means to said second prosthetic means, and wherein said link means includes a ball stud having one end thereof pivotally connected to said second prosthetic means by said pin and the other end thereof receiving a ball which pivotally engages said first prosthetic means, whereby said first prosthetic means can pivot relative to said pin during a first instance of motion and said first prosthetic means can pivot about said ball during a second instance of motion.

Claim 9

An applicance for replacement of a disabled human joint comprising: first prosthetic means including a stem member adapted for fixation in a first skeleton element and further including a first joint-forming member at one end of said stem member, said first joint-forming member having a convexly shaped articulation surface; second prosthetic means including a second stem member adapted for fixation in a second skeleton element disposed adjacent said first skeleton element and further including a second joint-forming member at one end of said second prosthetic means, said second joint-forming member having a concavely shaped articulation surface engageable with said convexly shaped articulation surface; link means cooperating to couple said first and second prosthetic means so that said convexly shaped articulation surface and said concavely shaped articulation surface are in slidable rotational contact with one another; and pivot means connecting one end of said link means to at least one of said prosthetic means, said pivot means includes a pin for connecting said link means to said second prosthetic means, and wherein said link means includes a ball stud having one end thereof pivotally connected to said second prosthetic means by said pin and the other end thereof receiving a ball which pivotally engages said first prosthetic means, whereby said first prosthetic means can pivot relative to said pin during a first instance of motion and said first prosthetic means can pivot about said ball during a second instance of motion.

Claim 10

The appliance for replacement of a disabled human joint according to claim 7 further including stop means extending upwardly from said second prosthetic means and engageable with an opening in said first prosthetic means, said opening also forming a slot to receive said ball stud which has one end connected to said pin.