Automatic calibration system for computer-aided surgical instruments

• US 6,996,487 B2
• Filed: 03/15/2001
• Issued: 02/07/2006
• Est. Priority Date: 03/15/2000
• Status: Expired due to Term

• Current Assignee: ORTHOsoft ULC. (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Orthosoft Inc. (Zimmer Biomet Holdings, Inc.)
• Inventors: Jansen, Herbert André, Amiot, Louis-Philippe, Jutras, Sébastien, Brosseau, Éric, C⊙té, Gabriel
• Primary Examiner(s): Tsai, Carol S. W.
• Application Number:
  US10/220,303
• Publication Number:
  US 20030040879A1
• Time in Patent Office: 1,790 Days
• Field of Search: 702/107, 702/150, 702/152, 600/104, 600/117, 600/411, 600/414, 600/423, 606/1
• US Class Current: 702/107
• CPC Class Codes: A61B 2017/00725 Calibration or performance testing
• CPC Class Codes: A61B 2034/2055 Optical tracking systems
• CPC Class Codes: A61B 2034/2068 using pointers, e.g. pointers having reference marks for determining coordinates of body points
• CPC Class Codes: A61B 2090/3983 Reference marker arrangements for use with image guided surgery
• CPC Class Codes: A61B 34/20 Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis
• CPC Class Codes: A61B 90/10 for stereotaxic surgery, e.g. frame-based stereotaxis
• CPC Class Codes: A61B 90/11 with guides for needles or instruments, e.g. arcuate slides or ball joints

Abstract

A system for automatic calibration of instruments (S) having varying cross-sectional dimensions within a predetermined range and having detectable elements (110, 112, 113, 114) thereon for computer-aided surgery, comprising a calibration base (C) having detectable elements (43, 44, 46, 48) secured thereto for detecting a position and an orientation thereof in space by sensors (204) connected to a position calculator (202). The calibration base is adapted to receive and to releasably secure a working shaft (100) of any of the instruments (S) and provides an abutting surface (14) for a tip (102) thereof in such a way that a position and orientation of the tip (102) of the instrument (S) secured therein is calculable when working shaft cross-section dimensions thereof are known. The position calculator (202) receives instrument data (214) and calibration data (218) from an operator through a user interface (206) and stores the instrument data (214) and calibration data (218) for subsequent calibrations.

Claims

1. A calibration base to automatically calibrate any of a plurality of instruments having varying cross-sectional dimensions within a predetermined range for computer-aided surgery, each of the instrument, having a detectable portion, a working shaft and a tip at an end of the working shaft, said calibration base comprising;

first detectable means secured thereto for detecting a position and an orientation thereof in space by sensor means connected to a position calculator; and

said calibration base adapted to receive and to releasably secure the working shaft of any of the instruments and providing a first abutting surface for the tip thereof in such a way that a position and orientation of the tip of any of the instruments secured therein is calculable when working shaft cross-section dimensions thereof are known;

whereby any of the instruments is calibrated when the position and orientation of the tip of the working shaft thereof is calculated.

2. The calibration base as defined in claim 1, wherein the first abutting surface extends in a direction generally opposed to a longitudinal axis of the working shaft of any one of the instruments.

3. The calibration base as defined in claim 2, wherein the working shaft of any of the instruments is abutted against a second and a third abutting surface.

4. The calibration base as defined in claim 3, wherein said second, and said third abutting surfaces define a V-shaped channel.

5. The calibration base as defined in claim 4, wherein said first, second end third abutting surfaces are each in a perpendicular relation with respect one to another.

6. The calibration base as defined claim 1, wherein the working shaft of any one of the instruments is releasably secured against abutting surfaces of said calibration bass by a biasing member.

7. The calibration base as defined in claim 6, wherein said biasing member comprises a spring-loaded lever.

8. The calibration base as defined in claim 7, wherein said lever has a generally rounded end surface for engaging contact with the working shaft.

9. The calibration base as defined in claim 1, wherein said first detectable means comprises three optically detectable spheres.

10. The calibration base as defined in claim 9, wherein each said detectable sphere is retro-reflective.

11. The calibration base as defined in claim 9, wherein said detectable spheres are detachable from said calibration base.

12. The calibration base as defined in claim 1, wherein said first detectable means are disposed in a concavity of said calibration base for impact protection thereof.

13. The calibration base as defined in claim 12, wherein said concavity is comprised of at least a pair of protrusions.

14. A method for calibrating any of a plurality of instruments having varying cross-sectional dimensions within a predetermined range with a position calculator connected to sensor means for computer-aided surgery, any one of the instruments having first detectable means being secured thereto and being releasably secured for calibration in a calibration base having second detectable means, said method comprising the steps of:

(i) detecting a position and orientation in space of said first and second detectable means by said sensor means;

(ii) receiving instrument data; and

(iii) calculating a position and orientation of a tip of any one of the instruments secured in said calibration base with respect to said second detectable means as a function of said instrument data whereby the instrument is calibrated with respect to said first detectable means.

15. The method as defined in claim 14, wherein the step (ii) includes receiving said instrument data from an operator through a user interface.

16. The method as defined in claim 14, wherein the step (iii) includes comparing the calculated position and orientation with a stored reference position and orientation of the tip of a same instrument as calculated in a previous calibration of the same instrument.

17. The method as defined in claim 16, wherein the step (iii) includes prompting an operator to verify the instrument if the calculated position and orientation is outside tolerances of the position and orientation of the previous calibration of the same instrument and waiting for an operator signal to proceed with a subsequent calibration calculation.

18. The method as defined in claim 17, wherein the step (iii) is repeated until the position and orientation of the previous calibration of the same instrument within said tolerances is attained.

19. The method according to claim 18, wherein the step (iii) includes asking the operator about setting a same position and orientation as calculated by at least two subsequent calibration calculation as a new accepted calibration calculation.

20. The method as defined in claim 15, wherein said instrument data includes one of identification data relating to instrument cross sectional dimension data stored by said position calculator and of instrument cross-sectional dimension data to be stored by said position calculator for subsequent calibrations.

21. A position calculator computer program product comprising code means recorded in a computer readable memory for executing a method for calibrating any of a plurality of instruments having varying cross-sectional dimensions within a predetermined range with a position calculator connected to sensor means for computer-aided surgery, any one of the instruments having first detectable means being secured thereto and being releasably secured for calibration in a calibration base having second detectable means, said method comprising the steps of:

(i) detecting a position and orientation in space of said first and second detectable means by said sensor means;

(ii) receiving instrument data; and

(iii) calculating a position and orientation of a tip of any one of the instruments secured in said calibration base with respect to said second detectable means as a function of said instrument data whereby the instrument is calibrated with respect to said first detectable means.

22. A System for automatic calibration of instruments for computer-aided surgery, comprising:

a calibration base to automatically calibrate any of a plurality of instruments having varying cross-sectional dimensions within a predetermined range for computer-aided surgery, each of the instruments having a detectable portion, a working shaft and a tip at an end of the working shaft, said calibration base comprising first detectable means secured thereto for detecting a position and an orientation thereof in space by sensor means connected to a position calculator, and said calibration base adapted to receive and to releasably secure the working shaft of any of the instruments and providing a first abutting surface for the tip thereof in such a way that a position and orientation of the tip of any of the instruments secured therein is calculable when working shaft cross-section dimensions thereof are known, whereby any of the instruments is calibrated when the position and orientation of the tip of the working shaft thereof is calculated;

said detectable portion on the instruments comprising second detectable means for space positioning of the instruments, said second detectable means being adapted to be secured to any of the instruments;

said sensor means for detecting a position and orientation in space of said first and second detectable means; and

a position calculator connected to said sensor means for calculating a position and orientation of the tip of the working shaft of any of the instruments secured in said calibration base with respect to the first detectable means according to a method comprising the steps of (i) detecting a position and orientation in space of said first and second detectable means by said sensor means, (ii) receiving instrument data, and (iii) calculating a position and orientation of a tip of any one of the instruments secured in said calibration base with respect to said first detectable means as a function of said instrument data;

whereby any of the instruments is calibrated with respect to said second detectable means when the position and orientation of the tip of the working shaft thereof is calculated.

23. The system as claimed in claim 22, wherein said second detectable means comprises three other optically detectable spheres.

24. The system as claimed in claim 23, wherein each said other detectable sphere is retro-reflective.

25. A method for calibrating instruments with a position calculator connected to sensor mean for computer-aided surgery, the instruments having detectable means being secured thereto, said method comprising the steps of:

(i) detecting a position and orientation in space of said detectable means by the sensor means;

(ii) calculating a position and orientation of a predetermined portion of any one of the instruments with respect to said detectable means; and

(iii) comparing the calculated position and orientation with a stored reference position and orientation of the predetermined portion of a same instrument as calculated in a previous calibration of the same instrument, and prompting an operator to verify the instrument if the calculated position and orientation is outside tolerances of the position and orientation of the previous calibration of the same instrument and waiting for an operator signal before repeating the steps (i), (ii) and (iii),

whereby the instrument calibration is validated if the calculated position and orientation is within tolerances of the position and, orientation of the previous calibration of the same instrument.

26. The method as defined in claim 25, wherein the step (iii) is repeated until the position and orientation of the previous calibration of the same instrument within said tolerances is attained.

27. The method as defined in claim 26, wherein the step (iii) includes asking the operator about setting a same position and orientation as calculated by at least two subsequent calibration calculation as a new accepted calibration calculation.

28. The method as defined in claim 25, wherein the step (iii) includes accepting instrument identification data from a user, storing the position and orientation from the previous calibration in association with the identification data and requesting the user to identify the instrument prior to the steps (i), (ii) and (iii).

29. A position calculator computer program product comprising code means recorded in a computer readable memory for executing a method for calibrating instruments with a position calculator connected to sensor means for computer-aided surgery, the instruments having detectable means being secured thereto, said method comprising the steps of:

(i) detecting a position and orientation in space of said detectable means by the sensor means,

(ii) calculating a position and orientation of a predetermined portion of any of one of the instruments with respect to said detectable means; and

(iii) comparing the calculated position and orientation with a stored reference position and orientation of the predetermined portion of a same instrument as calculated in a previous calibration of the name instrument, and prompting an operator to verify the instrument if the calculated position and orientation is outside tolerances of the position and orientation of the previous calibration of the name instrument and waiting for an operator signal before repeating the steps (i), (ii) and (iii);

whereby the instrument calibration is validated if the calculated position and orientation is within tolerances of the position and orientation of the previous calibration of the same instrument.