System and Method for Prosthetic Fitting and Balancing in Joints

• US 20120290088A1
• Filed: 06/05/2012
• Published: 11/15/2012
• Est. Priority Date: 03/19/2002
• Status: Abandoned Application

• 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.
• Application Number:
  US13/489,333
• Publication Number:
  US 20120290088A1
• Time in Patent Office: Days
• US Class Current: 623/14.12
• 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 device for intraoperative use in balancing joint forces and verifying the placement of the tibial component in total knee arthroplasty includes a spacer defining an enclosure; the spacer is sized to engage a top portion of the tibial component. A sensor array is embedded in the spacer, the sensor array measures forces on the spacer. A wireless transceiver is embedded in the spacer and forwards the output to a processor. The processor is analyzes the output and creates a pressure distribution graph indicative of the forces on the spacer, thereby assisting a surgeon in performing selective soft tissue release or component positioning in connection with surgical implantation of an orthopedic knee prosthesis.

Claims

1. A device for intraoperative use in balancing joint forces and verifying the placement of the tibial component in total knee arthroplasty comprising:

a spacer defining an enclosure, the spacer sized to engage a top portion of the tibial component;

a sensor array embedded in the spacer, the sensor array arranged to create an output indicative of the forces on the spacer;

a wireless transceiver embedded in the spacer and arranged to forward the output to a processor;

the processor arranged to analyze the output and create a pressure distribution graph indicative of the forces on the spacer;

thereby assisting a surgeon in performing selective soft tissue release or component positioning in connection with surgical implantation of an orthopedic knee prosthesis.

2. The device of claim 1, including a signal conditioning and signal transmitting circuit capable of sending the output through wireless communication to a receiver operatively connected to the processor.

3. The device of claim 1, wherein the spacer includes a power supply disposed inside a tibial post of tibial component, and wherein the power supply is insulated to thereby prevent patient injury from leakage or microshock.

4. The device of claim 1, further comprising a joint angle sensor communicatively coupled to the processor, the joint angle sensor measuring an angle of a knee joint.

5. The device of claim 1, further comprising a ligament tension sensor communicatively coupled to the processor, the ligament tensions sensor measuring tension of a knee ligament.

6. The device of claim 5, wherein the ligament tension sensor is attached to an outer knee ligament.

7. The device of claim 5, wherein the outer knee ligament is a medal cruciate ligament.

8. The device of claim 5, further comprising a plurality of ligament sensors, each ligament sensor being attached to an outer knee ligament.

9. The device of claim 1, further comprising a femoral component for attachment to an end of a femur.

10. The device of claim 9, wherein the spacer includes a pair of opposed faces, a first face including a pair of condyle recesses and an extension for slidably engaging a groove in a femoral component, the extension preventing lateral movement between the spacer and the femoral component while allowing the spacer to rotate relative to the femoral component.

11. The device of claim 10, wherein the spacer includes an elevated face opposite of the first face.

12. The device of claim 11, further comprising a tibial tray for attachment to a tibia.

13. The device of claim 12, wherein the elevated face cooperates with the tibial tray to form a snap-fit connection.

14. The device of claim 11, wherein the elevated face includes a plurality of recesses for receiving sensors in the sensor array.

15. The device of claim 1, wherein at least one sensor in the sensor array is a strain gage.

16. The device of claim 1, wherein the pressure distribution graph is a three dimensional pressure distribution graph.

17. The device of claim 1, wherein the spacer is bioengineered to remain in a human knee after total knee arthroplasty.

18. The device of claim 1, wherein the processor compares the output to pre-determined pressure criteria.

19. The device of claim 1, wherein the pressure distribution graph displays pressure distribution as a function of joint angle.

20. The device of claim 1, wherein the pressure distribution graph displays pressure distribution as a function of ligament tension.