SYSTEM AND METHOD FOR PROSTHETIC FITTING AND BALANCING IN JOINTS

• US 20090299483A1
• Filed: 08/11/2009
• Published: 12/03/2009
• Est. Priority Date: 03/19/2002
• Status: Active Grant

• Current Assignee: Board of Trustees of The University of Illinois
• Original Assignee: Board of Trustees of The University of Illinois
• Inventors: Amirouche, Farid, Gonzalez, Mark H.
• Granted Patent: US 8,197,549 B2
• Time in Patent Office: Days
• US Class Current: 623/20.29
• CPC Class Codes: A61B 2090/064 for measuring force, pressure or mechanical tension
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/031 Intracranial pressure
• CPC Class Codes: A61B 5/076 Permanent implantations telemetry using implanted circuitry A61B5/0031; implanted stimulators for therapy A61N1/3605, A61N1/362, A61N1/372
• CPC Class Codes: A61B 5/103 Detecting, measuring or recording devices for testing the shape, pattern, colour, size or movement of the body or parts thereof, for diagnostic purposes A61B5/08 takes precedence; measuring aids for tailors A41H1/00; measuring instruments specially adapted for dentistry A61C19/04
• CPC Class Codes: A61B 5/107 Measuring physical dimensions, e.g. size of the entire body or parts thereof
• CPC Class Codes: A61B 5/4528 Joints A61B5/4533, A61B5/4538 take precedence
• CPC Class Codes: A61B 5/4533 Ligaments
• CPC Class Codes: A61F 2/32 for the hip
• CPC Class Codes: A61F 2/38 for elbows or knees
• CPC Class Codes: A61F 2/3804 for elbows
• CPC Class Codes: A61F 2/3859 Femoral components
• CPC Class Codes: A61F 2/3886 for stabilising knees against anterior or lateral dislocations
• CPC Class Codes: A61F 2/389 Tibial components A61F2/3868 takes precedence
• CPC Class Codes: A61F 2/40 for shoulders
• CPC Class Codes: A61F 2/4202 for ankles
• CPC Class Codes: A61F 2/4225 for feet, e.g. toes
• CPC Class Codes: A61F 2/4241 for hands, e.g. fingers
• CPC Class Codes: A61F 2/4657 Measuring instruments used for implanting artificial joints for surgical instruments A61B90/06
• CPC Class Codes: A61F 2/468 Testing instruments for artificial joints for testing non-implantable prostheses A61F2/76
• CPC Class Codes: A61F 2/4684 : Trial or dummy prostheses
• CPC Class Codes: A61F 2002/30133 : kidney-shaped or bean-shaped
• CPC Class Codes: A61F 2002/30449 : the adhesive being cement
• CPC Class Codes: A61F 2002/305 : Snap connection
• CPC Class Codes: A61F 2002/30604 : modular
• CPC Class Codes: A61F 2002/3067 : for data transfer
• CPC Class Codes: A61F 2002/30784 : Plurality of holes
• CPC Class Codes: A61F 2002/30953 : using a remote computer network, e.g. Internet
• CPC Class Codes: A61F 2002/30955 : using finite-element analysis
• CPC Class Codes: A61F 2002/4631 : the prosthesis being specially adapted for being cemented
• CPC Class Codes: A61F 2002/4632 : using computer-controlled surgery, e.g. robotic surgery
• CPC Class Codes: A61F 2002/4666 : for measuring force, pressure or mechanical tension
• CPC Class Codes: A61F 2002/4668 : for measuring angles
• CPC Class Codes: A61F 2002/4696 : optical
• CPC Class Codes: A61F 2220/0025 : Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/005 : using adhesives
• CPC Class Codes: A61F 2230/0015 : Kidney-shaped, e.g. bean-shaped
• CPC Class Codes: A61F 2250/0002 : for data transfer
• 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 2310/00029 : Cobalt-based alloys, e.g. Co-Cr alloys or Vitallium
• CPC Class Codes: G16H 10/60 : for patient-specific data, e.g. for electronic patient records
• CPC Class Codes: G16H 20/30 : relating to physical therapies or activities, e.g. physiotherapy, acupressure or exercising
• CPC Class Codes: G16H 50/50 : for simulation or modelling of medical disorders

Abstract

A system and method for prosthesis fitting in joints comprising an artificial condyle and a spacer which cooperates with the condyle to form an artificial joint. The spacer embedded with at least one sensor which is responsive to a force generated between the condyle and the spacer. The artificial joint is adapted to move between a flexed position and an extended position defining a range of motion. The sensor is responsive to the force and generates an output representative of that force. The output is transmitted, either wirelessly or other, to a processor which utilizes an analysis program to display a representation of the forces applied. A practitioner utilizing the displayed analysis may intraoperatively determine the adjustments and balancing required within the artificial joint. The system may also utilize a ligament tension sensor which generates generates data representative of tension on a ligament of the artificial joint, and a joint angle sensor responsive to the range of motion of the artificial joint. The processor may be adapted to store the outputted sensor data to provide the practitioner with statistically relevant historical data.

Claims

1. A system for prosthesis fitting in joints comprising:

an artificial condyle;

a spacer, the spacer cooperating with the condyle to form an artificial joint, the spacer adapted to support a force from the condyle, the artificial joint being adapted to move between a flexed position and an extended position defining a range of motion;

a sensor embedded within the spacer, the sensor being responsive to the force, wherein the sensor generates an output representative of the force;

a processor having a memory, the processor being operatively coupled to the sensor, the processor memory being adapted to store the output representative of the force on the spacer by the condyle;

a computer analysis program stored on the processor memory, the computer analysis program being adapted to analyze the output representative of the force on the spacer.

2. A system for prosthesis fitting in joints as defined in claim 1, wherein the artificial joint is moveable through a range of motion, and wherein the sensor is arranged to provide a plurality of outputs each corresponding to a plurality of angles of the artificial joint within the range of motion.

3. A system for prosthesis fitting in joints as defined in claim 1, wherein the sensor is a strain gage, the strain gage being adapted to generate a voltage in response to the forces on the spacer.

4. A system for prosthesis fitting in joints as defined in claim 1, wherein the sensor comprises an array of individual sensors embedded in the spacer.

5. A system for prosthesis fitting in joints as defined in claim 4, wherein each of the individual sensors is embedded within a recess formed in the spacer.

6. A system for prosthesis fitting in joints as defined in claim 1, wherein the spacer comprises a transceiver having a memory, the transceiver being operatively coupled to the sensor.

7. A system for prosthesis fitting in joints as defined in claim 6, wherein the transceiver is arranged to wirelessly communicate with the processor.

8. A system for prosthesis fitting in joints as defined in claim 1, further comprising a database, wherein the database is adapted to store the output representative of the force on the spacer.

9. A system for prosthesis fitting in joints as defined in claim 1, wherein the computer analysis program is a finite element analysis program.

10. A system for prosthesis fitting in joints as defined in claim 9, wherein the finite element analysis program is adapted to output a pressure topography graph.

11. A system for prosthesis fitting in joints as defined in claim 10, further comprising a display, wherein finite element analysis program is adapted to output the pressure topography graph on display.

12. A system for prosthesis fitting in joints as defined in claim 1, further comprising a ligament tension sensor, the tension sensor adapted for placement on a ligament and arranged to produce an output indicative of a tensile force applied to the ligament.

13. A system for prosthesis fitting in joints as defined in claim 12, further comprising a display, wherein the data representative of the force is illustrated as a function of the tensile force applied to the ligament.

14. A system for prosthesis fitting in joints as defined in claim 2, further comprising a joint angle sensor, the joint angle sensor being responsive to the range of motion of the artificial joint, wherein the sensor generates data representative of an angle of the artificial joint.

15. A system for prosthesis fitting in joints as defined in claim 13, further comprising a display, wherein the data representative of the force is illustrated as a function of the joint angle.

16. A system for prosthesis fitting in joints as defined in claim 2, including a jig arranged to move the artificial joint through the range of motion.

17. A system for prosthesis fitting in joints as defined in claim 15, wherein the jig is arranged to move the artificial joint at a controlled rate of flexion.

18. A system for prosthesis fitting in joints as defined in claim 15, wherein the jig includes an angle sensor.

19. A system for prosthesis fitting in joints as defined in claim 15, wherein the jig is arranged to control at least one of a varus angle and a valgus angle.

20. A system for prosthesis fitting in joints as defined in claim 15, wherein the jig is arranged to apply a controlled load to the artificial joint.

21. A system for prosthesis fitting in joints as defined in claim 1, further comprising:

a ligament tension sensor, the tension sensor being responsive to the range of motion of the artificial joint, wherein the sensor generates data representative of tension on a ligament of the joint;

a joint angle sensor, the joint angle sensor being responsive to the range of motion of the artificial joint, wherein the sensor generates data representative of an angle of the artificial joint; and

wherein the data representative of the force is illustrated as a function of the joint angle and as a function of the ligament tension.

22. A system for prosthesis fitting in joint arthroplasty comprising:

an artificial condyle;

a spacer, the spacer cooperating with the condyle to form an artificial joint, the spacer adapted to support a force from the condyle, the artificial joint being adapted to move between a flexed position and an extended position defining a range of motion;

a sensor embedded within the spacer, the sensor being responsive to the force, wherein the sensor generates an output representative of the force;

a ligament tension sensor, the tension sensor being responsive to the range of motion of the artificial joint, wherein the sensor generates data representative of tension on a ligament of the artificial joint;

a joint angle sensor, the joint angle sensor being responsive to the range of motion of the artificial joint, wherein the sensor generates data representative of an angle of the artificial joint;

a processor having a memory, the processor being operatively coupled to the sensor, the processor memory being adapted to store the output representative of the force on the spacer by the condyle;

a computer analysis program stored on the processor memory, the computer analysis program being adapted to intraoperatively analyze the output representative of the force on the spacer, the data representative of an angle of the artificial joint, and the data representative of tension on a ligament of the artificial joint.

23. A system of claim 22, wherein the artificial joint is moveable through a range of motion, and wherein the sensor is arranged to provide a plurality of outputs each corresponding to a plurality of angles of the artificial joint within the range of motion.

24. A system of claim 23, wherein each of the individual sensors is embedded within a recess formed in the spacer.

25. A system of claim 22, wherein the spacer comprises a transceiver having a memory, the transceiver being operatively coupled to the sensor and wherein the transceiver is arranged to wirelessly communicate with the processor.

26. A system of claim 22, further comprising a database, wherein the database is adapted to store the output representative of the force on the spacer, the data representative of an angle of the artificial joint, and the data representative of tension on a ligament of the artificial joint

27. A system of claim 22, wherein the computer analysis program is a finite element analysis program.

28. A system of claim 27, wherein the finite element analysis program is adapted to output a pressure topography graph and wherein the computer analysis program is adapted to receive and output load threshold limits to the pressure topography graph.

29. (canceled)

30. (canceled)

31. (canceled)

32. (canceled)

33. (canceled)

34. (canceled)

35. (canceled)

36. (canceled)

37. A method for prosthesis fitting in joints comprising:

providing an artificial condyle;

providing a spacer, the spacer cooperating with the condyle to form an artificial joint, the spacer adapted to support a force from the condyle, the artificial joint being adapted to move between a flexed position and an extended position defining a range of motion;

embedding a sensor within the spacer, the sensor being responsive to the force, wherein the sensor generates an output representative of the force;

storing the output representative of the force on the spacer by the condyle in a processor having a memory, the processor being operatively coupled to the sensor;

analyzing the output representative of the force on the spacer in a computer analysis program stored on the processor memory.

38. A method for prosthesis fitting in joints as defined in claim 37, wherein the artificial joint is moveable through a range of motion, and further comprising arranging the sensor to provide a plurality of outputs each corresponding to a plurality of angles of the artificial joint within the range of motion.

39. A method for prosthesis fitting in joints as defined in claim 37, further comprising arranging the sensor as an array of individual sensors embedded in the spacer.

40. A method for prosthesis fitting in joints as defined in claim 39, further comprising embedding each of the individual sensors within a recess formed in the spacer.

41. A method for prosthesis fitting in joints as defined in claim 37, further comprising transmitting the output representative of the force via a transceiver having a memory, the transceiver being operatively coupled to the sensor.

42. A method for prosthesis fitting in joints as defined in claim 41, further comprising embedding the transceiver within the spacer

43. A method for prosthesis fitting in joints as defined in claim 41, further comprising transmitting the output representative of the force by wirelessly communicating with the processor.

44. A method for prosthesis fitting in joints as defined in claim 37, further comprising storing the output representative of the force on the spacer in a database.

45. A method for prosthesis fitting in joints as defined in claim 37, further comprising displaying the analysis of the output representative of the force on the spacer on a display.

46. A method for prosthesis fitting in joints as defined in claim 45, further comprising displaying a pressure topography graph.

47. A method for prosthesis fitting in joints as defined in claim 38, further comprising providing a ligament tension sensor, the tension sensor adapted for placement on a ligament and arranged to produce an output indicative of a tensile force applied to the ligament.

48. A method for prosthesis fitting in joints as defined in claim 47, further comprising displaying the data representative of the force as a function of the tensile force applied to the ligament.

49. A method for prosthesis fitting in joints as defined in claim 38, further comprising providing a joint angle sensor, the joint angle sensor being responsive to the range of motion of the artificial joint to generate data representative of an angle of the artificial joint.

50. A method for prosthesis fitting in joints as defined in claim 49, further comprising displaying the data representative of the force as a function of the joint angle.

51. A method for prosthesis fitting in joints as defined in claim 38, further comprising moving the artificial joint through the range of motion

52. A method for prosthesis fitting in joints as defined in claim 51, further comprising controlling the range of motion of the artificial joint with a jig.

53. A method for prosthesis fitting in joints as defined in claim 51, further comprising controlling the rate of flexion of the artificial joint with a jig.

54. A method for prosthesis fitting in joints as defined in claim 51, further comprising controlling the rate of extension of the artificial joint with a jig.

55. A method for prosthesis fitting in joints as defined in claim 51, further comprising controlling at least one of a vargus angle and a valgus angle of the artificial joint with a jig.

56. A method for prosthesis fitting in joints as defined in claim 51, further comprising controlling a load to the artificial joint with a jig.