Hinged joint system

• US 20050107886A1
• Filed: 12/20/2002
• Published: 05/19/2005
• Est. Priority Date: 12/21/2001
• Status: Active Grant

• Current Assignee: Smith & Nephew Incorporated (Smith & Nephew PLC)
• Original Assignee: Smith & Nephew Incorporated (Smith & Nephew PLC)
• Inventors: Marik, Greg, Salehi, Abraham, Weaver, Kevin, Crabtree, Paul, Harrison, Dennis, Huten, Denis, Langlais, Frantz
• Granted Patent: US 7,572,292 B2
• Time in Patent Office: Days
• US Class Current: 623/20.240
• CPC Class Codes: A61B 17/1659 Surgical rasps, files, planes, or scrapers
• CPC Class Codes: A61F 2/30744 End caps, e.g. for closing an endoprosthetic cavity
• CPC Class Codes: A61F 2/3845 allowing only for single rotation
• CPC Class Codes: A61F 2/385 also provided with condylar bearing surfaces
• CPC Class Codes: A61F 2/3854 with ball and socket joint
• CPC Class Codes: A61F 2/3859 Femoral components
• CPC Class Codes: A61F 2/3868 with sliding tibial bearing
• CPC Class Codes: A61F 2/389 Tibial components A61F2/3868 takes precedence
• CPC Class Codes: A61F 2/4684 Trial or dummy prostheses
• CPC Class Codes: A61F 2002/30032 differing in absorbability or resorbability, i.e. in absorption or resorption time
• CPC Class Codes: A61F 2002/30062 (bio)absorbable, biodegradable, bioerodable, (bio)resorbable, resorptive
• CPC Class Codes: A61F 2002/30131 horseshoe- or crescent- or C-shaped or U-shaped
• CPC Class Codes: A61F 2002/30332 Conically- or frustoconically-shaped protrusion and recess
• CPC Class Codes: A61F 2002/30433 using additional screws, bolts, dowels, rivets or washers e.g. connecting screws
• CPC Class Codes: A61F 2002/30495 using a locking ring
• CPC Class Codes: A61F 2002/30563 having elastic means or damping means, different from springs, e.g. including an elastomeric core or shock absorbers
• CPC Class Codes: A61F 2002/30604 modular
• CPC Class Codes: A61F 2002/30878 with non-sharp protrusions, for instance contacting the bone for anchoring, e.g. keels, pegs, pins, posts, shanks, stems, struts
• CPC Class Codes: A61F 2002/30884 Fins or wings, e.g. longitudinal wings for preventing rotation within the bone cavity
• CPC Class Codes: A61F 2210/0004 bioabsorbable
• CPC Class Codes: A61F 2220/0025 : Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0033 : made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2220/0041 : using additional screws, bolts, dowels or rivets, e.g. connecting screws
• CPC Class Codes: A61F 2230/0013 : Horseshoe-shaped, e.g. crescent-shaped, C-shaped, U-shaped

Abstract

Methods, systems, and devices for replacement of a joint with a prosthetic system that replicates the natural kinematics of the joint is disclosed. A prosthetic system according to one embodiment includes a tibial component having a tibial plateau and a tibial stem portion, the tibial plateau having a top side and a bottom side, a tibial insert, with a bearing surface, adapted to be positioned on the top side of the tibial plateau, a femoral component having a base portion and a central housing, the femoral component having an axis of extension-flexion rotation, the base portion having a pair of condyles, a mechanical linkage component linking the tibial component with the femoral component and with the tibial insert in between the tibial component and the femoral component, so that there is a center of contact between the condyles and the bearing surface, the mechanical linkage component adapted to allow the center of contact to move posteriorly during flexion, provide for the movement of the axis of extension-flexion rotation in the superior-inferior direction, and allow rotation of the tibial component, the bearing surface, and the femoral component about a superior-inferior axis in order to provide and control the natural kinematics of the knee joint.

Claims

1. A prosthetic system for performing the function of a knee joint, comprising:

(a) a tibial component having a tibial plateau and a tibial stem portion, the tibial plateau having a top side and a bottom side;

(b) a post having a proximal end and a distal end, the post adapted to project from the top side of the tibial plateau;

(c) a tibial insert having an aperture, the tibial insert adapted to be positioned on the top side of the tibial plateau with the tibial insert aperture adapted to receive the post;

(d) a femoral component having a base portion and a central housing having a femoral stem portion, the base portion having a pair of condyles and two posteriorly extending lobes;

(e) an axle adapted to connect to the lobes and extend between the lobes; and

(f) a link having an anterior end and a posterior end, the link adapted to be connected to the axle at the posterior link end and to receive the post at the anterior link end.

2. The prosthetic system of claim 1, further comprising an anterior aperture in the link and a cap adapted to mount on the post, the cap having a lip portion that extends beyond the diameter of the proximal end of the post, the anterior link aperture having a smaller diameter at its distal end, whereby the lip portion engages the smaller diameter of the anterior link aperture and prevents distraction of the prosthetic system.

3. The prosthetic system of claim 2, further comprising a cap retaining fastener for fastening the cap to the post.

4. The prosthetic system of claim 1, further comprising a posterior aperture in the link and two bushings adapted to fit in the posterior link aperture and receive the axle.

5. The prosthetic system of claim 1, further comprising two axle retaining fasteners adapted to retain the axle in place.

6. The prosthetic system of claim 5, wherein the axle retaining fasteners are clip-type fasteners.

7. The prosthetic system of claim 1, further comprising a Morse taper disposed on the distal end of the tibial stem portion.

8. The prosthetic system of claim 7, wherein the Morse taper is adapted to be inserted into an intramedullary canal of a patient'"'"'s tibia.

9. The prosthetic system of claim 7, further comprising a long tibial stem adapted to connect to the distal end of the Morse taper.

10. The prosthetic system of claim 1, further comprising a tibial body segment adapted to connect to the tibial stem portion.

11. The prosthetic system of claim 1, further comprising a Morse taper disposed on the proximal end of the femoral stem portion.

12. The prosthetic system of claim 11, wherein the Morse taper is adapted to be inserted into an intramedullary canal of a patient'"'"'s femur.

13. The prosthetic system of claim 11, further comprising a long femoral stem adapted to connect to the proximal end of the Morse taper.

14. The prosthetic system of claim 1, further comprising a femoral body segment adapted to connect to the femoral stem portion.

15. The prosthetic system of claim 1, wherein the tibial insert has a posterior notch and the top side of the tibial plateau has a posterior stop, whereby the tibial insert'"'"'s rotation is limited by the posterior stop.

16. The prosthetic system of claim 15, further comprising a bioresorbable bumper adapted to fit in the notch and surround the stop to prevent rotation of the tibial insert.

17. The prosthetic system of claim 1, wherein a first distance between the center point of the axle and the distal portion of the condyles is different than a second distance between the center point of the axle and the posterior portion of the condyles.

18. The prosthetic system of claim 2, wherein the femoral component is pre-assembled and the appropriately sized tibial insert and corresponding cap are selected during the replacement of the knee joint.

19. The prosthetic system of claim 1, wherein the link links the tibial component with the femoral component and with the tibial insert in between the tibial component and the femoral component so that there is a center of contact between the condyles and a bearing surface of the tibial insert, the link adapted to move in the superior-inferior directions and restrained from movement in the anterior-posterior directions, wherein the center of contact between the condyles and bearing surface moves in the anterior-posterior direction as the femoral component moves through extension and flexion.

20. The prosthetic system of claim 19, wherein the link and tibial insert are adapted to rotate about an inferior-superior axis.

21. The prosthetic system of claim 1, wherein the link links the tibial component with the femoral component and with the tibial insert in between the tibial component and the femoral component so that there is a center of contact between the condyles and a bearing surface of the tibial insert, the link adapted to allow the center of contact to move posteriorly during flexion, provide for the movement of the axis of extension-flexion rotation in the superior-inferior direction, and allow rotation of the tibial component, the tibial insert, and the femoral component about a superior-inferior axis in order to provide and control the natural kinematics of the knee joint.

22. The prosthetic system of claim 1, further comprising cutting blocks;

reamers; and

trials.

23. The prosthetic system of claim 1, wherein the link is operative to produce relative anterior-posterior movement between the femoral component and the tibial insert during flexion of the prosthetic system while maintaining a fixed relationship between the femoral component and the tibial component in an anterior-posterior direction.

24. The prosthetic system of claim 23, wherein the femoral component is adapted to rotate about the axle and the link is adapted to move superiorly along the post during flexion of the prosthetic system.

25. A prosthetic system for performing the function of a knee joint, comprising:

(a) a tibial component having a tibial plateau and a tibial stem portion, the tibial plateau having a top side and a bottom side;

(b) a tibial insert adapted to be positioned on the top side of the tibial plateau, the tibial insert having a bearing surface;

(c) a femoral component having a central housing and a base portion with a pair of condyles, the femoral component having an axis of extension-flexion rotation, the condyles adapted to translate on the bearing surface;

(d) a mechanical linkage component linking the tibial component with the femoral component and with the tibial insert in between the tibial component and the femoral component so that there is a center of contact between the condyles and the bearing surface, the mechanical linkage component adapted to move in the superior-inferior directions and restrained from movement in the anterior-posterior directions, wherein the center of contact between the condyles and bearing surface moves in the anterior-posterior direction as the femoral component moves through extension and flexion.

26. The prosthetic system of claim 25, wherein the linkage component and tibial insert are adapted to rotate about an inferior-superior axis.

27. The prosthetic system of claim 25, wherein the tibial component has a post on the top side of the tibial plateau, the post having a proximal end and a distal end, the base portion of the femoral component having a pair of posteriorly extending lobes, and the mechanical linkage component comprises;

an axle adapted to connect to the lobes and extend between the lobes; and

a link having an anterior end and a posterior end, the link adapted to connect to the axle at the posterior end and receive the post at the anterior end.

28. The prosthetic system of claim 27, further comprising an anterior aperture in the link and a cap adapted to mount on the proximal end of the post, the cap having a lip portion that extends beyond the diameter of the post, the anterior link aperture having a smaller diameter at its distal end, whereby the lip portion engages the smaller diameter and prevents distraction.

29. The prosthetic system of claim 26, wherein the tibial insert has a posterior notch and the top side of the tibial plateau has a posterior stop, whereby the tibial insert'"'"'s rotation is limited by the posterior stop.

30. The prosthetic system of claim 29, further comprising a bioresorbable bumper adapted to fit in the notch and surround the stop to prevent rotation of the tibial insert.

31. A prosthetic system for performing the function of a knee joint, comprising:

(a) a tibial component having a tibial plateau and a tibial stem portion, the tibial plateau having a top side and a bottom side;

(b) a tibial insert adapted to be positioned on the top side of the tibial plateau, the tibial insert having a bearing surface;

(c) a femoral component having a base portion and a central housing, the femoral component having an axis of extension-flexion rotation, the base portion having a pair of condyles;

(d) a mechanical linkage component linking the tibial component with the femoral component and with the tibial insert in between the tibial component and the femoral component so that there is a center of contact between the condyles and the bearing surface, the mechanical linkage component adapted to allow the center of contact to move posteriorly during flexion, provide for the movement of the axis of extension-flexion rotation in the superior-inferior direction, and allow rotation of the tibial component, the tibial insert, and the femoral component about a superior-inferior axis in order to provide and control the natural kinematics of the knee joint.

32. The prosthetic system of claim 31, wherein the tibial component has a post on the top side of the tibial plateau, the post having a proximal end and a distal end, the base portion of the femoral component having two posteriorly extending lobes, and the mechanical linkage component comprises;

an axle adapted to connect to the lobes and extend between the lobes; and

a link having an anterior end and a posterior end, the link adapted to connect to the axle at the posterior end and receive the post at the anterior end.

33. The prosthetic system of claim 32, further comprising an anterior aperture in the link and a cap adapted to mount on the proximal end of the post, the cap having a lip portion that extends beyond the diameter of the post, the anterior link aperture having a smaller diameter at its distal end, whereby the lip portion engages the smaller diameter and prevents distraction.

34. The prosthetic system of claim 31, wherein the tibial insert has a posterior notch and the top side of the tibial plateau has a posterior stop, whereby the rotation of the tibial insert is limited by the posterior stop.

35. The prosthetic system of claim 34, further comprising a bioresorbable bumper adapted to fit in the notch surrounding the stop to prevent rotation of the tibial insert.

36. A system for surgical replacement of a joint, comprising:

(a) cutting blocks;

(b) reamers;

(c) trials; and

(d) a prosthetic joint comprising,

(i) a tibial component having a tibial plateau and a tibial stem portion, the tibial plateau having a top side and a bottom side and a posterior stop on the top side;

(ii) a post having a proximal end and a distal end, the post adapted to project from the top side of the tibial plateau;

(iii) a cap adapted to mount on the proximal end of the post, the cap having a lip portion that extends beyond the diameter of the post,

(iv) a tibial insert having an aperture, the tibial insert adapted to be positioned on the top side of the tibial plateau with the tibial insert aperture adapted to receive the post and the cap, the tibial insert having a posterior notch, whereby the rotation of tibial insert is limited by the posterior stop;

(v) a bioresorbable bumper adapted to fit in the notch and surround the stop to prevent rotation of the tibial insert for a limited period of time;

(vi) a femoral component having a base portion and a central housing having a femoral stem portion, the base portion having a pair of condyles and two posteriorly extending lobes;

(vii) an axle adapted to extend between the lobes;

(viii) a link having an anterior link aperture and a posterior link aperture, the anterior link aperture having a smaller diameter at its distal end, whereby the lip portion of the cap engages the smaller diameter of the anterior link aperture and prevents distraction of the prosthetic system; and

(ix) two bushings adapted to fit in the posterior link aperture and receive the axle, whereby the axle passes through the bushings and the posterior link aperture so that the link can rotate on the axle.

37. A method of replacing a knee joint in a patient, comprising:

(a) resecting the proximal end of the patient'"'"'s tibia to expose the tibial intramedullary canal of the tibia;

(b) resecting the distal end of the patient'"'"'s femur to expose the femoral intramedullary canal;

(c) connecting a tibial stem and a femoral stem to a prosthetic system, the prosthetic system comprising;

(i) a tibial component having a tibial plateau and a tibial stem portion, the tibial plateau having a top side and a bottom side, the tibial stem portion adapted to receive the tibial stem;

(ii) a tibial insert adapted to be positioned on the top side of the tibial plateau, the tibial insert having a bearing surface;

(iii) a femoral component having a base portion, a central housing, and a femoral stem portion, the femoral component having an axis of extension-flexion rotation, the base portion having a pair of condyles, the femoral stem portion adapted to receive the femoral stem;

(iv) a mechanical linkage component linking the tibial component with the femoral component and with the tibial insert in between the tibial component and the femoral component so that there is a center of contact between the condyles and the bearing surface, the mechanical linkage component adapted to allow the center of contact to move posteriorly during flexion, provide for the movement of the axis of extension-flexion rotation in the superior-inferior direction, allow rotation of the tibial component, the tibial insert, and the femoral component about a superior-inferior axis, and offset the axis of extension-flexion rotation from the superior-inferior axis in order to provide and control the natural kinematics of the knee joint;

(d) inserting the femoral stem into the femoral intramedullary canal; and

(e) inserting the tibial stem into the tibial intramedullary canal.

38. The method of claim 37, wherein the tibial insert has a notch and the top side of the tibial plateau has a stop, whereby the tibial insert'"'"'s rotation is limited by the stop.

39. The method of claim 38, further comprising:

(f) placing a bioresorbable bumper in between the notch of the tibial insert and the stop of the tibial plateau.

40. The method of claim 37, wherein a surgeon can convert to the prosthetic system from a primary or revision prosthesis with common bone cuts and instrumentation and wherein three additional cuts from a primary or revision prosthesis are needed to accommodate the prosthetic system.

41. The method of claim 37, wherein a post projects from the tibial plateau and a cap is adapted to mount on the post, the tibial insert adapted to receive the post and the cap, and the mechanical linkage component adapted to receive the post and the cap.

42. The method of claim 41, wherein the femoral component is pre-assembled and the appropriately sized tibial insert and corresponding cap are selected during the replacement of the knee joint.