Implants for Altering Wear Patterns of Articular Surfaces

• US 20090226068A1
• Filed: 03/05/2009
• Published: 09/10/2009
• Est. Priority Date: 03/05/2008
• Status: Active Grant

• Current Assignee: Conformis Incorporated
• Original Assignee: Conformis Incorporated
• Inventors: Lang, Philipp, Fitz, Wolfgang, Bojarski, Raymond
• Granted Patent: US 8,682,052 B2
• Time in Patent Office: Days
• US Class Current: 382/131
• CPC Class Codes: A61B 2034/108 Computer aided selection or customisation of medical implants or cutting guides
• CPC Class Codes: A61B 34/10 Computer-aided planning, simulation or modelling of surgical operations
• CPC Class Codes: A61F 2/30756 Cartilage endoprostheses A61F2/3603 takes precedence
• CPC Class Codes: A61F 2/30942 for designing or making customized prostheses, e.g. using templates, CT or NMR scans, finite-element analysis or CAD-CAM techniques
• CPC Class Codes: A61F 2/3603 implanted without ablation of the whole natural femoral head endoprosthetic cartilage A61F2/30756
• CPC Class Codes: A61F 2/38 for elbows or knees
• CPC Class Codes: A61F 2/3859 Femoral components
• CPC Class Codes: A61F 2/3872 Meniscus for implantation between the natural bone surfaces
• CPC Class Codes: A61F 2/3877 Patellae or trochleae
• CPC Class Codes: A61F 2/389 Tibial components A61F2/3868 takes precedence
• CPC Class Codes: A61F 2/4081 Glenoid components, e.g. cups
• CPC Class Codes: A61F 2/488 Means for detecting or monitoring wear
• CPC Class Codes: A61F 2002/30062 (bio)absorbable, biodegradable, bioerodable, (bio)resorbable, resorptive
• CPC Class Codes: A61F 2002/30065 thermoplastic, i.e. softening or fusing when heated, and hardening and becoming rigid again when cooled
• CPC Class Codes: A61F 2002/30324 differing in thickness
• CPC Class Codes: A61F 2002/30757 made of a sheet covering the natural articular surface, e.g. cap
• CPC Class Codes: A61F 2002/30761 Support means for artificial cartilage, e.g. cartilage defect covering membranes
• 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 2002/30879 Ribs
• CPC Class Codes: A61F 2002/30884 Fins or wings, e.g. longitudinal wings for preventing rotation within the bone cavity
• CPC Class Codes: A61F 2002/30891 : Plurality of protrusions
• CPC Class Codes: A61F 2002/30894 : inclined obliquely with respect to each other
• CPC Class Codes: A61F 2002/3093 : for promoting ingrowth of bone tissue
• CPC Class Codes: A61F 2002/30934 : Special articulating surfaces
• CPC Class Codes: A61F 2002/30939 : Means for modifying the geometry of articulating surfaces, e.g. for compensating excessive clearance caused by wear
• CPC Class Codes: A61F 2002/30943 : using mathematical models
• CPC Class Codes: A61F 2002/30948 : using computerized tomography, i.e. CT scans
• CPC Class Codes: A61F 2002/30952 : using CAD-CAM techniques or NC-techniques
• CPC Class Codes: A61F 2002/30953 : using a remote computer network, e.g. Internet
• CPC Class Codes: A61F 2002/30957 : using a positive or a negative model, e.g. moulds
• CPC Class Codes: A61F 2002/3096 : trimmed or cut to a customised size
• CPC Class Codes: A61F 2002/3895 : unicompartimental
• CPC Class Codes: A61F 2002/4633 : for selection of endoprosthetic joints or for pre-operative planning
• CPC Class Codes: A61F 2210/0004 : bioabsorbable
• CPC Class Codes: A61F 2210/0071 : thermoplastic
• CPC Class Codes: A61F 2310/00011 : Metals or alloys
• CPC Class Codes: A61F 2310/00017 : Iron- or Fe-based alloys, e.g. stainless steel
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00047 : Aluminium or Al-based alloys
• CPC Class Codes: A61F 2310/00065 : Manganese or Mn-based alloys
• CPC Class Codes: A61F 2310/00071 : Nickel or Ni-based alloys
• CPC Class Codes: A61F 2310/00077 : Copper or Cu-based alloys
• CPC Class Codes: A61F 2310/00083 : Zinc or Zn-based alloys
• CPC Class Codes: A61F 2310/00107 : Palladium or Pd-based alloys
• CPC Class Codes: A61F 2310/00113 : Silver or Ag-based alloys
• CPC Class Codes: A61F 2310/00119 : Tin or Sn-based alloys
• CPC Class Codes: A61F 2310/00131 : Tantalum or Ta-based alloys
• CPC Class Codes: A61F 2310/00149 : Platinum or Pt-based alloys
• CPC Class Codes: A61F 2310/00155 : Gold or Au-based alloys
• CPC Class Codes: A61F 2310/00179 : Ceramics or ceramic-like structures
• CPC Class Codes: A61F 2310/00365 : Proteins; Polypeptides; Degradation products thereof
• CPC Class Codes: B33Y 70/00 : Materials specially adapted for additive manufacturing
• CPC Class Codes: B33Y 70/10 : Composites of different types of material, e.g. mixtures of ceramics and polymers or mixtures of metals and biomaterials
• CPC Class Codes: B33Y 80/00 : Products made by additive manufacturing

Abstract

Methods and devices for correcting wear pattern defects in joints. The methods and devices described herein allow for the restoration of correcting abnormal biomechanical loading conditions in a joint brought on by wear pattern defects, and also can, in embodiments, permit correction of proper kinematic movement.

Claims

1. A method for designing a orthopedic device that alters a wear pattern on an articular surface of a joint, comprising

a) receiving image data associated with the joint;

b) determining a wear pattern of an articular surface at least in part from the image data;

c) designing an orthopedic device based at least in part on the image data, wherein the orthopedic device is designed to alter the wear pattern of the articular surface to a revised wear pattern.

2. The method of claim 1, wherein the image data is derived from a technique selected from the group consisting of arthroscopy, arthrotomic examination, gait analysis, and imaging analysis;

or a combination thereof.

3. The method of claim 1, wherein the step of designing includes altering the wear pattern at least in part by adjusting the location of the wear pattern on the articular surface.

4. The method of claim 1, wherein the step of designing includes altering the wear pattern at least in part by distributing the load that will be placed on the articular surface.

5. The method of claim 1, wherein the step of designing includes altering the wear pattern at least in part by reducing point loading on the articular surface.

6. The method of claim 1, wherein the image data is received via a computer network.

7. The method of claim 1, wherein the wear pattern is determined automatically.

8. The method of claim 1, further comprising determining a second wear pattern of a second articular surface of the joint from the image data.

9. The method of claim 8, further comprising designing the orthopedic device based at least in part on the image data associated with the second articular surface, wherein the orthopedic device is designed to alter the second wear pattern of the second articular surface to a second revised wear pattern.

10. The method of claim 9, wherein the orthopedic device is a bicompartmental resurfacing device for a knee.

11. The method of claim 1, further comprising determining a second wear pattern of a second articular surface of the joint from the image data.

12. The method of claim 11, further comprising designing a second orthopedic device based at least in part on the image data associated with the second articular surface, wherein the second orthopedic device is designed to alter the second wear pattern of the second articular surface to a second revised wear pattern.

13. The method of claim 12, wherein the first orthopedic device is a tibial tray for a knee and the second orthopedic device is a second tibial tray for the knee.

14. The method of claim 1, further comprising designing a second orthopedic device based at least in part on the image data, wherein the second orthopedic device is designed to alter the wear pattern of the articular surface to the revised wear pattern.

15. The method of claim 1, wherein the first orthopedic device is a tibial tray for a knee joint and the second orthopedic device is a unicompartmental femoral resurfacing device for the knee joint.

16. The method of claim 1, wherein the orthopedic device is a replacement hip joint.

17. The method of claim 1, wherein the orthopedic device is a knee replacement device including a femoral component and a tibial component.

18. The method of claim 1, wherein the orthopedic device is designed using a library of design elements.

19. The method of claim 1, wherein the orthopedic device is designed to include at least one surface that conforms to an existing surface of the joint.

20. The method of claim 1, wherein the orthopedic device is designed to include at least one surface that is derived from an existing surface of the joint.

21. The method of claim 20, wherein the derived surface excludes a defect of the existing surface.

22. The method of claim 20, wherein the derived surface approximates an ideal surface of the joint.

23. The method of claim 20, wherein the derived surface approximates a healthy surface of the joint.

24. The method of claim 1, wherein the orthopedic device is designed to include at least one curve derived from an existing surface of the joint.

25. The method of claim 24, wherein the derived curve excludes a defect of the existing joint.

26. The method of claim 24, wherein the derived curve approximates an ideal curve of the joint.

27. The method of claim 24, wherein the derived curve approximates a healthy surface of the joint.

28. The method of claim 1, wherein the orthopedic device is designed to include at least one dimension that is derived from an existing dimension of the joint.

29. The method of claim 28, wherein the derived dimension excludes a defect of the existing joint.

30. The method of claim 28, wherein the derived dimension approximates an ideal dimension of the joint.

31. The method of claim 28, wherein the derived dimension approximates a dimension associated with a healthy joint.

32. The method of claim 1, wherein the orthopedic device is designed to be placed at least in part on cartilage associated with the joint.

33. The method of claim 1, wherein the orthopedic device is designed to be placed at least in part on subchondral bone associated with the joint.

34. The method of claim 1, further comprising producing the orthopedic device.

35. The method of claim 34, wherein the orthopedic device is produced using direct digital manufacturing.

36. The method of claim 34, wherein the orthopedic device is produced by tailoring a precursor orthopedic device.

37. The method of claim 36, wherein the precursor orthopedic device is selected from a library of orthopedic devices.

38. The method of claim 34, wherein the orthopedic device is produced by altering a standard orthopedic device.

39. The method of claim 38, wherein the standard orthopedic device is selected from an inventory of orthopedic devices

40. A method for preparing an implant for correcting an articular surface wear pattern, comprising

a) obtaining an image of an articular surface;

b) analyzing the image for the presence or absence of wear pattern indicia;

c) determining a wear pattern from the wear pattern indicia; and

d) providing an implant having a characteristic topography for correcting the wear pattern.

41. The method of claim 40, wherein the implant is designed to include an interior surface that is a mirror image of the articular surface.

42. An implant for correcting an articular surface wear pattern, comprising an implant body having a characteristic topography, an interior surface, and an outer surface, where the implant body topography is derived from a wear pattern analysis of the articular surface.

43. The implant of claim 42, wherein the interior surface is a mirror image of the articular surface.

44. A method of joint arthroplasty, the method comprising:

a) obtaining an image of a surface of a joint;

the surface of the joint including a wear pattern;

b) deriving a shape of the joint surface based, at least in part, on the image;

c) providing an implant having a surface based on the surface of the joint, wherein the implant is configured to alter the wear pattern of the joint.

45. The method of claim 44, wherein obtaining the image includes an imaging technique selected from the group consisting of x-ray imaging and processing;

fluoroscopy;

digital tomosynthesis;

ultrasound;

optical coherence, conventional, cone beam, or spiral computed tomography (CT);

single photon emission tomography (SPECT);

bone scan;

positron emission tomography (PET);

magnetic resonance imaging (MRI);

thermal imaging; and

optical imaging, or a combination thereof.

46. The method according to claim 44, wherein the joint is one of a knee, a shoulder, a hip, a vertebrae, an elbow, an ankle, a foot, a toe, a hand, a wrist and a finger.

47. The method according to claim 44, wherein the wear pattern is based, at least in part, on one of a presence, absence, location, distribution, depth, area, or dimensions of cartilage loss;

presence, absence, location, distribution, depth, area, or dimensions of subchondral cysts;

presence, absence, location, distribution, depth, area, or dimensions of subchondral sclerosis;

presence, absence, location, distribution, volume, area, depth or dimensions of a subchondral bone plate abnormality;

presence, absence, location, distribution, or dimensions of a subchondral bone deformity;

presence, absence, or severity of a varus or valgus deformity;

presence, absence or severity of recurvatum or antecurvatum; and

presence, absence, location, distribution, volume, depth or dimensions of bone marrow edema.

48. The method of claim 44, wherein the surface of the implant is substantially at least one of rigid, non-pliable, non-flexible and non-resilient.

49. The method of claim 44, wherein the surface of the implant is at least one of a polymer, a cross-linked polymer, a ceramic, a metal, an alloy and a ceramic-metal composite.

50. The method of claim 44, wherein providing the surface of the implant includes at least one of rapid prototyping, laser cutting, laser sintering, electron beam melting, casting and milling.

51. The method of claim 44, further comprising positioning the implant adjacent an implantation site.

52. The method of claim 51, wherein the surface of the implant is shaped prior to positioning the implant.

53. A method for preparing an implant for accommodating an articular surface wear pattern, comprising

a) obtaining an image of an articular surface;

b) analyzing the image for the presence or absence of wear pattern indicia;

c) determining a wear pattern from the wear pattern indicia; and

d) providing an implant having a surface with a characteristic topography for accommodating the wear pattern.

54. The method of claim 53, wherein the surface is derived from the articular surface.

55. An implant for improving an articular surface wear pattern, comprising an implant body having a characteristic topography, an interior surface, and an outer surface, where the implant body topography is derived from a wear pattern analysis of the articular surface.

56. The implant of claim 55, wherein the interior surface is a mirror image of the articular surface.