Femoral knee prosthesis system with augments and multiple lengths of sleeves sharing a common geometry

Patent metadata

Field	Value
Publication number	US-9532879-B2
Application number	US-201313832415-A
Country	US
Kind code	B2
Filing date	Mar 15, 2013
Priority date	Sep 20, 2012
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

A modular knee prosthesis system includes a femoral component having a stem, a plurality of different sizes of sleeves mountable on the stem, and a plurality of different sizes of augments mountable on the femoral component. The system is modular, and provides the surgeon with the option of distally offsetting the joint line by selecting the size of sleeve that will provide the desired joint line. The different sizes of sleeves have different axial lengths but share a common geometry along a substantial part of their lengths so that the same bone cavity will accept multiple sizes of sleeves.

First claim

The invention claimed is:

1. A modular knee prosthesis system, comprising: a distal femoral implant component having (i) a pair of spaced, curved distal condylar surfaces, (ii) a distal bone-facing surface, and (iii) a stem having an outer surface tapering from a distal end in a proximal direction, the outer surface of the stem having a maximum outer diameter at the distal end and a smaller outer diameter at a second position proximal to the distal end, a distal femoral augment configured to be secured to the distal bone-facing surface of the distal femoral implant component, a proximal tibial implant component having an articulating surface to receive and articulate with the distal condylar surfaces of the distal femoral implant component and a stem, the stem having an outer surface tapering from a proximal end in the distal direction, the outer surface of the stem having a maximum outer diameter at the proximal end and a smaller outer diameter at a second position distal to the proximal end, a first metaphyseal member having an outer surface that tapers in the proximal direction and an inner surface defining a tapered bore sized and shaped to be mountable on the stem of one of the implant components and to create a frictional lock between the stem and the first metaphyseal member, the outer surface of the first metaphyseal member comprising a stepped portion having a plurality of steps, each step having a maximum medial-lateral dimension and a maximum anterior-posterior dimension, the stepped portion having an overall axial length L, and a second metaphyseal member having an outer surface that tapers in the proximal direction and an inner surface defining a tapered bore sized and shaped to be mountable on the stem of one of the implant components and to create a frictional lock between the stem and the second metaphyseal member, the outer surface of the second metaphyseal member comprising a stepped portion having a plurality of steps, each step having a maximum medial-lateral dimension and a maximum anterior-posterior dimension, the stepped portion having an overall axial length L+X, wherein (i) the maximum medial-lateral dimension of each step over the axial length L of the stepped portion of the second metaphyseal member is the same as the maximum medial-lateral dimension of each step over the axial length L of the stepped portion of the first metaphyseal member and the maximum anterior-posterior dimension of each step over the axial length L of the stepped portion of the second metaphyseal member is the same as the maximum anterior-posterior dimension of each step over the axial length L of the stepped portion of the first metaphyseal member so that the same prepared bone space will receive either the first metaphyseal member or the stepped portion of the second metaphyseal member having the axial length L, and (ii) the distal femoral augment has a thickness that is substantially equal to X, wherein the axial height of each step over the axial length L of the first metaphyseal member is equal to the axial height of each step over the axial length L of the second metaphyseal member,
wherein the distal femoral augment further includes (i) a tapered anterior surface configured to engage an anterior chamfer surface of the distal femoral implant component, (ii) a tapered posterior surface to engage a posterior chamfer surface of the distal femoral implant component when the distal femoral implant augment is secured to the distal bone-facing surface of the distal femoral augment component, and (iii) a posterior notch sized to receive a posterior femoral augment.

2. The modular knee prosthesis system of claim 1 , wherein: the tapered bore of the first metaphyseal member is sized and shaped to be mountable on the stem of the distal femoral implant component and to create a frictional lock between the stem of the distal femoral implant component and the first metaphyseal member, the tapered bore of the second metaphyseal member is sized and shaped to be mountable on the stem of the distal femoral implant component and to create a frictional lock between the stem of the distal femoral implant component and the first metaphyseal member, the contact between the articulating surface of the proximal tibial implant component and the distal condylar surfaces of the distal femoral implant component defines a first joint line when the distal femoral implant component is assembled with the first metaphyseal member, the contact between the articulating surface of the proximal tibial implant component and the distal condylar surfaces of the distal femoral implant component defines a second joint line when the distal femoral implant component is assembled with the second metaphyseal member, and the second joint line is more distal than the first joint line.

3. The modular knee prosthesis of claim 2 , wherein the distance between the first joint line and the second joint line corresponds with the difference between the overall axial lengths of the first metaphyseal member and the second metaphyseal member and defines a distal offset.

4. The modular knee prosthesis system of claim 1 , further comprising:
a third metaphyseal member having an outer surface that tapers in a proximal direction and an inner surface defining a tapered bore sized and shaped to be mountable on the stem of one of the implants components and to create a frictional lock between the stem and the third metaphyseal member, the outer surface of the third metaphyseal member comprising a stepped portion having a plurality of steps, each step having a maximum medial-lateral dimension and a maximum anterior-posterior dimension, the stepped portion having an overall axial length L+X+Y,
a second distal femoral augment configured to be secured to the distal bone-facing surface of the distal femoral implant component in place of the first distal femoral augment, the second distal femoral augment having a thickness equal to X+Y,
wherein:
the maximum medial-lateral dimension and maximum anterior-posterior dimension of each step over the axial length L of the stepped portion of the third metaphyseal member is the same as the maximum medial-lateral dimension and maximum anterior-posterior dimension of each step over the axial length L of the stepped portion of the first metaphyseal member and the second metaphyseal member; and
the maximum medial-lateral dimension and maximum anterior-posterior dimension of each step over the axial length L+X of the stepped portion of the third metaphyseal member is the same as the maximum medial-lateral dimension and maximum anterior-posterior dimension of each step over the axial length L+X of the stepped portion of the second metaphyseal member.

5. An orthopaedic knee prosthesis system, comprising: a femoral prosthetic component including a medial condyle surface and a lateral condyle surface, a first sleeve component including (i) a first end configured to be separately secured to the femoral prosthetic component and (ii) a tapered body extending from a second end positioned opposite the first end, a second sleeve component including (i) a first end configured to be separately secured to the femoral prosthetic component in place of the first sleeve component, (ii) a first tapered body extending distally from a second end positioned opposite the first end, and (iii) a second tapered body extending distally from the first tapered body, and a distal femoral augment configured to be secured to a first bone-facing surface of the femoral prosthetic component, wherein the tapered body of the first sleeve component and the first tapered body of the second sleeve component have a first outer three-dimensional geometry, and the second tapered body of the second sleeve component has a second outer three-dimensional geometry different from the first outer three-dimensional ge

Assignees

• Depuy Ireland Ultd Co

Inventors

• Lieberman Jay R
• Sordelet Benjamin J
• Spencer Jones Richard
• Vendrely Timothy G
• Wainscott Stephanie M
• Cook Michael A
• Chaney Rebecca L
• Wyss Joseph G
• Hazebrouck Stephen A
• Matyas Aaron J

Classifications

• A61F2/30734 Primary

  Modular inserts, sleeves or augments, e.g. placed on proximal part of stem for fixation purposes or wedges for bridging a bone defect · CPC title

• A61F2002/30738

  Sleeves · CPC title

• A61F2/3836 Primary

  Special connection between upper and lower leg, e.g. constrained · CPC title

• A61F2002/30736

  Augments or augmentation pieces, e.g. wedges or blocks for bridging a bone defect · CPC title

• A61F2/38

  for elbows or knees · CPC title