Knee prosthesis

An artificial knee comprising first and second pivotally interconnected knee components, and first and second interengaging brake components for locking the knee components together, the first and second brake components being associated respectively with the first and second knee components, wherein one of the brake components is made of a resiliently deformable material, and the arrangement is such that, when the artificial knee is subjected to a first load condition, the brake components are substantially free to slide against one another, and, when the artificial knee is under a second, higher load condition, said one brake component is resiliently deformed against the other brake component to lock the two brake components together, thereby locking the two knee components together, wherein the first and second brake components are provided with interengaging surfaces which are inclined to the axis about which the two knee components are pivoted, and the first and second brake components constitute the pivotal interconnection between the two knee components, the interengaging surfaces being configured so that side play of the knee components is prevented, the first brake component being an externally screw-threaded member, the flanks of the threads being inclined to the pivot axis, the first brake component being made of a generally rigid material such as stainless steel, the second brake component having a base portion and a pair of arms, the internal surface of the base portion being rounded and being provided with an internal screw thread which complements the external screw thread of the first brake component, the second brake component being said one brake component, and said resiliently deformable material being a plastics material.

An artificial knee comprising first and second pivotally interconnected knee components, and first and second interengaging brake components for locking the knee components together, the first and second brake components being associated respectively with the first and second knee components, wherein one of the brake components is made of a resiliently deformable material, and the arrangement is such that, when the artificial knee is subjected to a first load condition, the brake components are substantially free to slide against one another, and, when the artificial knee is under a second, higher load condition, said one brake component is resiliently deformed against the other brake component to lock the two brake components together, thereby locking the two knee components together, wherein the first and second brake components are provided with interengaging surfaces which are inclined to the axis about which the two knee components are pivoted, and the first and second brake components constitute the pivotal interconnection between the two knee components, one of said first and second brake components being made of a self-lubricating material, and the other of said brake components being made of a generally rigid material and being generally cylindrical with inclined surfaces for interengagement with complementary inclined surfaces of said one brake component, the inclined surfaces of said other brake component defining a plurality of wedge-shaped pockets along a generating line of the cylindrical surface of that component.