Device, sensor, sensor element and method for measuring the profile of a spinal column and for measuring changes in the profile of the spinal column

• US 8,241,231 B2
• Filed: 03/07/2007
• Issued: 08/14/2012
• Est. Priority Date: 03/27/2006
• Status: Expired due to Fees

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Bausewein, Andreas, Bierhoff, Thomas, Goldbeck, Dirk David, Happel, Tobias, Schrage, Hans-Jürgen
• Primary Examiner(s): Hindenburg, Max
• Assistant Examiner(s): Danega, Renee
• Application Number:
  US12/225,708
• Publication Number:
  US 20090234250A1
• Time in Patent Office: 1,987 Days
• Field of Search: 600/594, 250/227.14
• US Class Current: 600/594
• CPC Class Codes: A61B 2562/0266 Optical strain gauges
• CPC Class Codes: A61B 2562/164 the sensor is mounted in or on a conformable substrate or carrier
• CPC Class Codes: A61B 2562/187 Strain relief means
• CPC Class Codes: A61B 5/1077 Measuring of profiles
• CPC Class Codes: A61B 5/1116 Determining posture transitions
• CPC Class Codes: A61B 5/1126 using a particular sensing technique
• CPC Class Codes: A61B 5/4566 Evaluating the spine A61B5/4561 takes precedence
• CPC Class Codes: A61B 5/6823 Trunk, e.g., chest, back, abdomen, hip

Abstract

The profile of the spinal column and changes in the profile of the spinal column are continuously measured during movement along the entire spinal column in all degrees of freedom of its deformation.

Claims

1. A device for measuring a profile of a spinal column, comprising:

one or more sensors each divided into one or more sensor element portions to continuously measure the profile of the spinal column; and

an electronic change measurement evaluator configured to connect to a sensor and to continuously measure changes to the profile of the spinal column during movement along the spinal column in degrees of freedom of deformation of the spinal column,

wherein with a plurality of the sensors, said sensors with respective sensor element portions thereof arranged such that the respective sensor element portions of the sensors are in succession of each other at intervals of adjacent vertebrae of the spinal column.

2. The device as claimed in claim 1, wherein at least one of said sensor element portions is sensitive to a deformation in a direction of at least one degree of freedom, that detects at least part of the spinal column to be measured.

3. The device as claimed in claim 1, wherein a sensor element portion comprises:

at least one optical waveguide extending over at least one part of the spinal column to be measured, having at least one bending-sensitive zone relative to a deformation in a direction of at least one degree of freedom;

at least one light source radiating a constant light output at a first end of said at least one optical waveguide; and

at least one receiver measuring output light incident at a second end of said at least one optical waveguide, said receiver being connected to the evaluator.

4. The device as claimed in claim 1, wherein each sensor element portion includes at least one optical waveguide having at least one bending-sensitive zone relative to a deformation in a direction of at least one degree of freedom, for continuously measuring the profile of the spinal column and changes to the profile of the spinal column within a respective sensor element portion and/or over adjacent sensor element portions.

5. The device as claimed in claim 4,

wherein each of the optical waveguides has at least one bending-sensitive zone within a respective sensor element portion for measuring one respective degree of freedom, in lateral and dorsal movement as well as in torsion.

6. A sensor that is part of a device for continuously measuring a profile of a spinal column and changes to the profile during movement along the spinal column in degrees of freedom of deformation of the spinal column, said sensor comprising:

one or more sensors each divided into one or more sensor element portions to continuously measure the profile of the spinal column; and

an electronic change measurement evaluator configured to connect to the sensor and to continuously measure changes to the profile of the spinal column during movement along the spinal column in degrees of freedom of deformation of the spinal column,

wherein with a plurality of the sensors, said sensors with respective sensor element portions of thereof arranged such that the respective sensor element portions of the sensors are in succession of each other at intervals of adjacent vertebrae of the spinal column.

7. The sensor as claimed in claim 6, wherein each sensor includes:

at least one optical waveguide segment having at least one bending-sensitive zone relative to a deformation in a direction of at least one degree of freedom;

at least one light source radiating a constant light output at a first end of the optical waveguide segment; and

at least one receiver measuring the output light incident at a second end of the optical waveguide segment.

8. The sensor as claimed in claim 7, further comprising a common elastically expandable strip-shaped support material on which said sensors are arranged and having mobility corresponding to the spinal column in the degrees of freedom of deformation thereof.

9. The sensor as claimed in claim 8, wherein the optical waveguide segments are arranged in a meandering manner on said support material.

10. The sensor as claimed in claim 8, further comprising support plates, having a high tensile strength but which are flexible, arranged on said strip-shaped support material, on which the optical waveguide segments are fastened and are arranged extending between adjacent support plates in arcuate expansion loops.

11. The sensor as claimed in claim 8, further comprising a protection mechanism to protect the strip-shaped support material from overexpansion.

12. The sensor as claimed in claim 11, wherein said protection mechanism includes tension straps arranged on both sides along longitudinal sides of said strip-shaped support material and tensioned beyond a definable expansion of said strip-shaped support material and thus prevent a further expansion of said strip-shaped support material.

13. A sensor element for use in a sensor that is part of a device for continuously measuring a profile of a spinal column and changes to the profile during movement along the spinal column in degrees of freedom of deformation of the spinal column, comprising:

at least one optical waveguide to extend over a part of the spinal column to be measured and having at least one bending-sensitive zone formed by partial geometric changes in a core-cladding transition zone and relative to a deformation in a direction of at least one degree of freedom,

wherein the optical waveguide has an interior and the partial geometric changes depending on a bending of the optical waveguide includes indentations in the core-cladding transition zone influencing scattering behavior and reflection behavior in the interior of the optical waveguide.

14. The sensor element as claimed in claim 13, further including one respective optical waveguide for each degree of freedom, each optical waveguide having at least one respective bending-sensitive zone designed for deformation in a respective direction of a respective degree of freedom.

15. The sensor element as claimed in claim 14, wherein the sensor element is provided for measuring a spinal column in the degrees of freedom, in dorsal and lateral movement and in torsion, and

wherein the sensor element includes three optical waveguides with at least one respective bending-sensitive zone measuring the respective degree of freedom.

16. The sensor element as claimed in claim 13, wherein the partial geometric changes in the core-cladding transition zone is produced by mechanical machining of the respective optical waveguide in a region of the core-cladding transition zone thereof.

17. The sensor element as claimed in claim 16, wherein the bending-sensitive zone of the respective optical waveguide is arranged on a peripheral position thereof.

18. A method of using one or more sensors and an electronic change measurement evaluator configured to connect to the sensors for continuously measuring a profile of a spinal column and changes to the profile of the spinal column during movement along the spinal column in degrees of freedom of deformation of the spinal column, comprising:

dividing each sensor into one or more sensor element portions to continuously measure the profile of the spinal column,

wherein with a plurality of the sensors, said sensor with respective sensor element portions thereof arranged such that the respective sensor element portions of the sensors are in succession of each other at intervals of adjacent vertebrae of the spinal column.

19. The method as claimed in claim 18, further comprising:

arranging at least one optical waveguide with a bending-sensitive zone for a sensor element portion,

wherein the optical waveguide is configured to receive light radiated into the optical waveguide to measure incident light output from the optical waveguide, and a deformation of the spinal column is determinable by comparing the incident light output with the light radiated into the optical waveguide.

20. A method as claimed in claim 19,

wherein said determining the deformation of the spinal column includes comparing the incident light output with the light radiated into the optical waveguide in a time-discrete manner, and

wherein said method further comprises storing the deformations thus determined.

21. A method as claimed in claim 18, further comprising fastening the sensors to a support strip.

22. A method as claimed in claim 21, wherein three respective sensors with optical waveguides having a bending-sensitive zone are provided for measuring one respective degree of freedom within each portion along the spinal column.

23. A method as claimed in claim 22, wherein the bending-sensitive zones of the optical waveguides are produced by mechanical machining of the optical waveguides.