Facet joint prosthesis measurement and implant tools
View Patent ↗The present invention provides tools and methods designed to aid in the placement of facet joint prosthesis at virtually all spinal levels. One aspect of the present invention is a measurement tool for installing a cephalad facet joint prosthesis including a fixation measurement element and a support arm element. This measurement tool assists in the selection and/or configuration of a cephalad facet joint prosthesis for implantation in a patient. Another aspect is a measurement tool for installing a caudal facet joint prosthesis including a stem element and a trial caudal bearing surface element. This measurement tool assists in the selection and/or configuration of a caudal facet joint prosthesis for implantation in a patient. Yet another aspect is a measurement tool holder including a measurement surface connected to a holder element. This tool holder assists in determining the measurements obtained with the caudal facet joint prosthesis measurement tool.
1. A caudal facet joint prosthesis measurement system comprising a measurement tool adapted and configured to determine a characteristic of a caudal facet joint prosthesis, the tool comprising a stem element and a trial caudal bearing surface element, the system further comprising a measurement tool holder adapted and configured to hold the measurement tool and to provide measurement of an angle between the stem element and the trial caudal bearing surface element.
2. The measurement system of claim 1 wherein a measurement surface of the measurement tool holder is adapted and configured to permit measurement of an angle in a horizontal plane between the stem element and the caudal bearing surface element of the caudal facet joint prosthesis measurement tool.
3. The measurement system of claim 1 wherein a measurement surface of the measurement tool holder is adapted and configured to permit measurement of an angle in a median plane between the stem element and the caudal bearing surface element of the caudal facet joint prosthesis measurement tool.
4. The measurement system of claim 1 wherein the measurement tool further comprises a fixed connection element positioned between the stern element and the trial caudal bearing surface element.
5. The measurement system of claim 1 wherein the measurement tool further comprises a moveable connection element positioned between the stem element and the trial caudal bearing surface element.
6. The measurement system of claim 1 wherein the measurement tool further comprises a lockable connection element positioned between the stem element and the trial caudal bearing surface element.
7. The measurement system of claim 1 wherein the measurement tool further comprises a polyaxial connection element positioned between the stem element and the trial caudal bearing surface element.
8. The measurement system of claim 1 wherein the measurement tool further comprises a lockable polyaxial connection element positioned between the stem element and the trial caudal bearing surface element.
9. The measurement system of claim 1 wherein the measurement tool comprises a radiopaque element.
10. The measurement system of claim 1 wherein the trial caudal bearing surface element is adapted and configured to replicate a target anatomical surface.
11. The measurement system of claim 1 wherein the trial caudal bearing surface element is adapted and configured to predict the location of a target anatomical position of an implanted element.
12. The measurement system of claim 11 wherein the trial caudal bearing surface element is adapted and configured to duplicate a target anatomical position of the implanted element.
13. A facet joint prosthesis measurement tool holder comprising a measurement surface connected to a holder element adapted and configured to hold a facet joint prosthesis measurement tool, wherein the measurement surface comprises two plates, the plates being at right angles to each other.
14. A facet joint prosthesis measurement tool holder comprising a measurement surface connected to a holder element adapted and configured to hold a facet joint prosthesis measurement tool, wherein the holder element is adapted and configured to permit measurement of an angle between a stem element and a caudal bearing surface element of the facet joint prosthesis measurement tool.
15. The measurement tool holder of claim 14 wherein the measurement surface is adapted and configured to permit measurement of an angle in a horizontal plane between the stem element and the caudal bearing surface element of the caudal facet joint prosthesis measurement tool.
16. The measurement tool holder of claim 14 wherein the measurement surface is adapted and configured to permit measurement of an angle in a median plane between the stem element and the caudal bearing surface element of the caudal facet joint prosthesis measurement tool.
17. The measurement tool holder of claim 14 wherein the measurement tool further comprises a fixed connection element positioned between the stem element and the trial caudal bearing surface element.
18. The measurement tool holder of claim 14 wherein the measurement tool further comprises a moveable connection element positioned between the stem element and the trial caudal bearing surface element.
19. The measurement tool holder of claim 14 wherein the measurement tool further comprises a lockable connection element positioned between the stem element and the trial caudal bearing surface element.
20. The measurement tool holder of claim 14 wherein the measurement tool further comprises a polyaxial connection element positioned between the stem element and the trial caudal bearing surface element.
21. The measurement tool holder of claim 14 wherein the measurement tool further comprises a lockable polyaxial connection element positioned between the stem element and the trial caudal bearing surface element.
22. The measurement tool holder of claim 14 wherein the measurement tool comprises a radiopaque element.
23. The measurement tool holder of claim 14 wherein the trial caudal bearing surface element is adapted and configured to replicate a target anatomical surface.
24. The measurement tool holder of claim 14 wherein the trial caudal bearing surface element is adapted and configured to predict the location of a target anatomical position of an implanted element.
25. The measurement tool holder of claim 24 wherein the trial caudal bearing surface element is adapted and configured to duplicate a target anatomical position of the implanted element.
26. A facet joint prosthesis measurement tool holder comprising a measurement surface connected to a holder element adapted and configured to hold a facet joint prosthesis measurement tool, wherein the measurement surface is adapted and configured to permit measurement of an angle between a stem element and a caudal bearing surface element of the facet joint prosthesis measurement tool.
27. The measurement tool holder of claim 26 wherein the measurement surface is adapted and configured to permit measurement of an angle in a horizontal plane between the stem element and the caudal bearing surface element of the caudal facet joint prosthesis measurement tool.
28. The measurement tool holder of claim 26 wherein the measurement surface is adapted and configured to permit measurement of an angle in a median plane between the stem element and the caudal bearing surface element of the caudal facet joint prosthesis measurement tool.
29. The measurement tool holder of claim 26 wherein the measurement tool further comprises a fixed connection element positioned between the stem element and the trial caudal bearing surface element.
30. The measurement tool holder of claim 26 wherein the measurement tool further comprises a moveable connection element positioned between the stem element and the trial caudal bearing surface element.
31. The measurement tool holder of claim 26 wherein the measurement tool further comprises a lockable connection element positioned between the stem element and the trial caudal bearing surface element.
32. The measurement tool holder of claim 26 wherein the measurement tool further comprises a polyaxial connection element positioned between the stem element and the trial caudal bearing surface element.
33. The measurement tool holder of claim 26 wherein the measurement tool further comprises a lockable polyaxial connection element positioned between the stem element and the trial caudal bearing surface element.
34. The measurement tool holder of claim 26 wherein the measurement tool comprises a radiopaque element.
35. The measurement tool holder of claim 26 wherein the trial caudal bearing surface element is adapted and configured to replicate a target anatomical surface.
36. The measurement tool holder of claim 26 wherein the trial caudal bearing surface element is adapted and configured to predict the location of a target anatomical position of an implanted element.
37. The measurement tool holder of claim 36 wherein the trial caudal bearing surface element is adapted and configured to duplicate a target anatomical position of the implanted element.
38. A facet joint prosthesis measurement tool holder comprising a measurement surface connected to a holder element adapted and configured to hold a facet joint prosthesis measurement tool, wherein the measurement surface has markings to permit measurement of an angle between a stem element and a caudal bearing surface element of the facet joint prosthesis measurement tool.