Hip joint prosthesis
First Claim
1. A fixture for a hip joint prosthesis which is adapted to be permanently anchored in an operational position in the neck of a human femur after resection of the femur head from the neck by translation of the fixture in a predetermined forward direction into a cylindrical bore having an open end in the femur neck outer surface exposed on resection of the femur neck and an axial extent in the predetermined forward direction from the open end towards the opposite outer surface of the femur below the greater trochanter, the fixture comprising:
- a forward section which comprises a cylindrical forward portion of a first diameter and a coaxial cylindrical rearward portion of a second diameter greater than the first diameter and which after translation of the fixture to the operational position of the fixture is disposed in the cylindrical bore; and
a rearward section connected to the cylindrical rearward portion of the forward section which is adapted in use to carry a prosthetic ball unit of the hip joint prosthesis and which after translation of the fixture to the operational position of the fixture is disposed outside of the bore in the femur neck,wherein the forward section is integrally formed such that the cylindrical forward and rearward portions of the forward section are rotatable and translate in unison when the forward section is translated to the operational position, and said portions are provided with external screw threads; and
wherein the first and second diameters and external screw threads of the cylindrical forward and rearward portions of the forward section are adapted such that the fixture is able to be translated to the operational position by screwing of the fixture into the cylindrical bore about the predetermined forward direction with the external screw threads of the cylindrical forward and rearward portions simultaneously turning in the bone tissue forming the boundary wall of the cylindrical bore.
1 Assignment
0 Petitions
Accused Products
Abstract
Hip joint prostheses are disclosed for permanent anchoring in the human hip joint of a ball unit in the neck of a human femur. The prosthesis include a first cylindrical fixture portion for extending from the collum femoris toward the outer side of the femur and a second cylindrical fixture portion for placement in the cancellus bone of the collum femoris, both of these portions including outer cylindrical surfaces with external self-tapping threads, and in which the first and second cylindrical fixture portions are joined into a single portion for insertion into a bore hole provided in the femur in a single operation.
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Citations
14 Claims
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1. A fixture for a hip joint prosthesis which is adapted to be permanently anchored in an operational position in the neck of a human femur after resection of the femur head from the neck by translation of the fixture in a predetermined forward direction into a cylindrical bore having an open end in the femur neck outer surface exposed on resection of the femur neck and an axial extent in the predetermined forward direction from the open end towards the opposite outer surface of the femur below the greater trochanter, the fixture comprising:
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a forward section which comprises a cylindrical forward portion of a first diameter and a coaxial cylindrical rearward portion of a second diameter greater than the first diameter and which after translation of the fixture to the operational position of the fixture is disposed in the cylindrical bore; and a rearward section connected to the cylindrical rearward portion of the forward section which is adapted in use to carry a prosthetic ball unit of the hip joint prosthesis and which after translation of the fixture to the operational position of the fixture is disposed outside of the bore in the femur neck, wherein the forward section is integrally formed such that the cylindrical forward and rearward portions of the forward section are rotatable and translate in unison when the forward section is translated to the operational position, and said portions are provided with external screw threads; and wherein the first and second diameters and external screw threads of the cylindrical forward and rearward portions of the forward section are adapted such that the fixture is able to be translated to the operational position by screwing of the fixture into the cylindrical bore about the predetermined forward direction with the external screw threads of the cylindrical forward and rearward portions simultaneously turning in the bone tissue forming the boundary wall of the cylindrical bore. - View Dependent Claims (4, 5, 6, 9, 10, 12, 13, 14)
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2. A fixture for a hip joint prosthesis which is adapted to be permanently anchored in an operational position in the neck of a human femur after resection of the femur head from the neck by translation of the fixture in a predetermined forward direction into a cylindrical bore having an open end in the femur neck outer surface exposed on resection of the femur neck and an axial extent in the predetermined forward direction from the open end towards the opposite outer surface of the femur below the greater trochanter, the fixture comprising:
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a forward section which comprises a cylindrical forward portion of a first diameter and a coaxial cylindrical rearward portion of a second diameter greater than the first diameter and which after translation of the fixture to the operational position of the fixture is disposed in the cylindrical bore; and a rearward section connected to the cylindrical rearward portion of the forward section which is adapted in use to carry a prosthetic ball unit of the hip joint prosthesis and which after translation of the fixture to the operation position of the fixture is disposed outside of the bore in the femur neck, wherein the forward section is integrally formed such that the cylindrical forward and rearward portions of the forward section are rotatable and translate in unison when the forward section is translated to the operational position, and said portions are provided with external screw threads; and wherein the first and second diameters and external screw threads of the cylindrical forward and rearward portions of the forward section are adapted such that the fixture is able to be translated to the operational position by screwing of the fixture into the cylindrical bore about the predetermined forward direction with the external screw threads of the cylindrical forward and rearward portions simultaneously turning in the bone tissue forming the boundary wall of the cylindrical bore, wherein the second diameter is selected such that when the fixture is in the operational position the external screw threads of the cylindrical rearward portion of the forward section register in cortical bone at the outer peripheral surface of the femur neck which forms at least a part of the adjacent boundary wall of the cylindrical bore, and wherein the first diameter is selected such that when the fixture is in the operation position the external screw threads of the cylindrical forward portion of the forward section register in cancellous bone which forms the adjacent boundary wall of the cylindrical bore. - View Dependent Claims (11)
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3. A fixture for a hip joint prosthesis which is adapted to be permanently anchored in an operational position in the neck of a human femur after resection of the femur head from the neck by translation of the fixture in a predetermined forward direction into a cylindrical bore having an open end in the femur neck outer surface exposed on resection of the femur neck and an axial extent in the predetermined forward direction from the open end towards the opposite outer surface of the femur below the greater trochanter, the fixture comprising:
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a forward section which comprises a cylindrical forward portion of a first diameter and a coaxial cylindrical rearward portion of a second diameter greater than the first diameter and which after translation of the fixture to the operational position of the fixture is disposed in the cylindrical bore; and a rearward section connected to the cylindrical rearward portion of the forward section which is adapted in use to carry a prosthetic ball unit of the hip joint prosthesis and which after translation of the fixture to the operational position of the fixture is disposed outside of the bore in the femur neck, wherein the forward section is integrally formed such that the cylindrical forward and rearward portion of the forward section are rotatable and translate in unison when the forward section is translated to the operational position, and said portions are provided with external screw threads; and wherein the first and second diameters and external screw threads of the cylindrical forward and rearward portion of the forward section are adapted such that the fixture is able to be translated to the operational position by screwing of the fixture into the cylindrical bore about the predetermined forward direction with the external screw threads of the cylindrical forward and rearward portions and simultaneously turning in the bone tissue forming the boundary wall of the cylindrical bore, and wherein the cylindrical forward portion of the forward section of the fixture is releasably securable to the cylindrical rearward portion of the forward section. - View Dependent Claims (7, 8)
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Specification