Bioabsorbable plates. fasteners, tools and method of using same

• US 20020004660A1
• Filed: 02/23/2001
• Published: 01/10/2002
• Est. Priority Date: 02/24/2000
• Status: Active Grant

• Current Assignee: Stryker Corporation
• Original Assignee: Stryker Instruments, A Division Of Stryker Corporation
• Inventors: Tyler, Douglas L. Sr., Longo, Paul T., Landeryou, Robert F., Ahola, Jon J., Diamond, D. Gregory, Henniges, Bruce D., Wasserman, Mark A., Forst, Peter, Tunc, Deger C., Salzberger, Mark T.
• Granted Patent: US 6,592,578 B2
• Time in Patent Office: Days
• US Class Current: 606/69
• CPC Class Codes: A61B 17/1655 for tapping
• CPC Class Codes: A61B 17/1728 for holes for bone plates or plate screws
• CPC Class Codes: A61B 17/808 Instruments for holding or positioning bone plates, or for adjusting screw-to-plate locking mechanisms
• CPC Class Codes: A61B 17/8085 with pliable or malleable elements or having a mesh-like structure, e.g. small strips A61B17/8071, A61B17/8076 take precedence
• CPC Class Codes: A61B 17/862 at the periphery of the screw head
• CPC Class Codes: A61B 17/865 Packages or dispensers for bone screws or threaded wires
• CPC Class Codes: A61B 17/8863 Apparatus for shaping or cutting osteosynthesis equipment by medical personnel
• CPC Class Codes: A61B 17/8883 the driver bit acting on the periphery of the screw head
• CPC Class Codes: A61B 17/8891 at its periphery
• CPC Class Codes: A61B 2017/00004 (bio)absorbable, (bio)resorbable, resorptive for implantable prostheses A61F2210/0004
• CPC Class Codes: A61B 50/33 Trays
• CPC Class Codes: A61B 90/92 coded with colour

Abstract

The present invention is a system for installing bioabsorbable plates for general bone repair, as for example, facial or cranial osteosynthesis. The present invention includes an improved plate and fastener system which reduces if not eliminates stresses within the plate. It also includes an improved fastener container and driver for handling and installing fasteners. The system employs a unique water bath for heating the bioabsorbable plate so they can be deformed to the contours of the bone being repaired. Additionally, there is a hand tool for localized heating and deformation of the plate when positioned against the bone to further ensure conformity with the bone structure. These and other features are contained within a kit which is easily sterilized.

Claims

1. A bioabsorbable plate and fastener comprising;

at least one fastener having a head portion and a threaded shank, said head having a top surface and a bottom surface, said shank extending from said bottom surface, said bottom surface having a convex shape;

a plate having a first thermo-chemical solid state in which said plate is rigid;

said plate further having a second thermo-chemical solid state in which said plate is deformable;

said plate further including at least two openings for receiving said fasteners;

said plate further including a relief area surrounding each of said openings to allow said fastener to seat within said bioabsorbable plate such that no part of the fastener extends above the surface of said plate when the fastener is applied;

said relief area is a generally concave surface surrounding each of said openings to provide a stable mating contact surface for mating with said bottom surface of said fastener to reduce tensile stresses in said plate and to allow proper seating of said fastener within said relief area.

2. The bioabsorbable plate and fastener of claim 1, wherein said bottom surface of said fastener and said relief area mate in generally surface to surface contact when said fastener is generally perpendicular to one of said openings and line contact when said fastener is not generally perpendicular to one of said openings.

3. The bioabsorbable plate and fastener of claim 1, wherein said plate presents a periphery adapted for repairing bone of varying size and contours.

4. The bioabsorbable plate and fastener of claim 3, wherein said periphery can include a variety of shapes.

5. The bioabsorbable plate and fastener of claim 3, wherein each of said variety of shapes corresponds to a specific color, said bioabsorbable plate being color coded to allow easy identification of the shape and size of the plate.

6. The bioabsorbable plate and fastener of claim 1, wherein said plate is identified by an identification mark designating a particular plate.

7. The bioabsorbable plate and fastener of claim 1, wherein said top surface of said head portion includes at least one recess for insertion of a driver to allow said fastener to be threaded into the bone surface being repaired;

8. The bioabsorbable plate and fastener of claim 7, wherein said fastener comprises one of a plurality of sizes.

9. The bioabsorbable plate and fastener of claim 8, wherein each of said plurality of sizes corresponds to a specific color, said fastener being color coded to allow easy identification of said fastener.

10. A fastener for attaching a bioabsorbable plate to bone structure comprising:

a head portion for contacting a bioabsorbable plate to hold the bioabsorbable plate against a bone surface to be repaired;

a shank portion extending from said head portion and including threads for providing threaded engagement with the bone surface being repaired;

said head portion includes at least two notches, said notches including side walls and a rear wall, said notches are separated about said head portion of said fastener, said notches being sized wherein said notches are adapted to receive features of a driver for driving the fastener into said bone structure, and said side walls provide a contact surface for the driver to thread said fastener into place.

11. The fastener as set forth in claim 10, wherein said side walls for each of said notches fall on lines that cross at a point outside the center area of said head portion, thereby concentrating the forces exerted onto said head portion into compressive stresses within said head portion to reduce failure.

12. The fastener as set forth in claim 10, wherein said rear wall provides frictional engagement with the driver to removably secure said fastener to the driver.

13. The fastener as set forth in claim 12, wherein said side walls for each of said notches fall on lines that cross at a point outside the center line of said head portion, thereby concentrating the forces exerted onto said head portion into compressive stresses within said head portion to reduce failure.

14. The fastener as set forth in the claim 10, wherein said rear wall includes a protrusion extending outwardly from said rear wall for engagement with a driver to removably secure said fastener to a driver.

15. The fastener as set forth in the claim 14, wherein said side walls for each of said notches fall on lines that cross at a point outside the center line of said head portion, thereby concentrating the forces exerted onto said head portion into compressive stresses within said head portion to reduce failure.

16. A driver for inserting fasteners into bone structure, said driver comprising;

an operative end for engagement with a fastener;

a handle portion opposite said operative end for allowing manual manipulation of said driver to insert the fastener; and

a clutch mechanism interconnecting said handle portion and said operative end for limiting the the operation of said driver between direct drive wherein said operative end is operatively fixed to said handle portion and a clutch drive wherein said operative end is operatively coupled to said amount of torque that can be transferred therebetween said clutch mechanism controlling handle to slip at a predetermined torque;

17. The driver as set forth in claim 16, wherein said handle portion includes a switch for selectively activating said clutch mechanism.

18. The device of claim 16, wherein said clutch mechanism includes a control ring, a pair of fingers and a blade, said control ring being mounted for movement with respect to said fingers to either engage said fingers and lock said fingers against said blade for direct drive operation or to disengage said fingers and allow said blade to move with respect to said fingers after a predetermined torque is exceeded.

19. A driver for inserting bioabsorbable fasteners into bone structure, said driver comprising:

a tool holder for receipt of a tool for driving a fastener into the bone structure;

a grip operatively connected to said tool holder and a torque limiting mechanism operatively connected between said grip and said tool holder, said torque limiting mechanism initially locking said grip with respect to said tool holder to apply a torque through said grip into said tool holder to drive the bioabsorbable fastener into the bone structure, said torque limiting mechanism unlocking said grip with respect to said tool holder when a predetermined torque is applied to said grip to stop applying a torque through said grip and into said tool holder to prevent damage to said bioabsorbable fastener.

20. The driver of claim 19, wherein said clutch mechanism includes a control ring, a pair of fingers and a blade, said blade is connected to said tool holder, said control ring being mounted for movement with respect to said fingers to either engage said fingers and lock said fingers against said blade for direct drive operation or to disengage said fingers and allow said blade to move with respect to said fingers after a predetermined torque is exceeded.

21. A driver for inserting fasteners for bioabsorbable plates, said driver comprising:

an operative end for engagement with a fastener; and

a handle portion opposite said operative end for allowing manual manipulation of said driver to insert the fastener;

said operative end including at least two fingers, each of said fingers including side walls and an internal wall, said side walls spaced to fit within notches in a head portion of the fastener.

22. The driver as set forth in claim 21, wherein said internal wall of at least one of said fingers frictionally engages the fastener to removably secure the fastener within said fingers of said driver.

23. The driver as set forth in claim 21, wherein said operative end is connected to said handle portion through a clutch mechanism for limiting the amount of torque that can be transferred therebetween.

24. The driver as set forth in claim 23, wherein said handle portion includes a switch for selectively activating said clutch mechanism.

25. The driver as set forth in claim 22, wherein said fingers have a thickness that is less than the depth of the notches on the fastener to allow said fingers to fit completely within the circumference of the head portion of the fastener to prevent interference with the bioabsorbable plate when the fastener is applied using said driver.

26. A hand held device for locally heating a portion of a bioabsorbable plate, said device comprising;

a body portion having a hand held section and a tip section;

said body portion defining a thermal mass for retaining heat within said body for transfer to said bioabsorbable plate;

said tip section holding a fluid for bridging said body portion and said plate to facilitate heat transfer from said body portion to said bioabsorbable plate.

27. The hand held device of claim 26, further including a cavity for retaining said fluid to said tip.

28. The hand held device of claim 26, wherein said tip has a roughened surface for retaining said fluid to said tip.

29. The apparatus as set forth in claim 27, wherein said tip includes a roughened surface surrounding said cavity on said tip to provide additional surface area for holding said fluid.

30. An apparatus as set forth in claim 26, wherein said body portion includes a fluid channel, said fluid channel including a first end at said tip and extending to a second end at a position within said body portion thereby creating a passage therebetween, said fluid channel being operable to receive and hold said fluid to be dispensed from said tip.

31. The apparatus as set forth in claim 30, wherein said device includes a sleeve extending about said body portion and including at least one hollow compressible bulb extending therefrom defining a cavity between said compressible bulb and said body portion, and said body portion including at least one opening positioned between said cavity and said second end of said fluid passage for allowing fluid communication between said cavity and said fluid passage.

32. The apparatus as set forth in claim 31, wherein said body portion includes a pair of o-rings for creating a seal between said body portion and said sleeve, said o-rings being spaced along said body portion such that said cavity, said opening and said second end of said fluid passage are disposed therebetween, whereby said cavity, said opening, and said fluid channel define a continuous variable volume chamber with only one aperture, said aperture being the first end of said fluid channel.

33. The apparatus as set forth in claim 32, wherein said fluid channel includes a branch channel extending from said fluid channel to a point adjacent said tip for allowing suction between said fluid channel and said fluid at the tip to be interrupted.

34. The apparatus as set forth in claim 30, wherein said body portion is made from a non-corrosive metal and said sleeve is made from an autoclavable insulating material.

35. The apparatus as set forth in claim 30, wherein said body portion includes a heating device for keeping the body and fluid that is within said fluid channel at a pre-determined temperature until the heated fluid is dispensed.

36. A portable bowl for containing a volume of heated fluid, said bowl comprising;

a base;

a reservoir for holding a volume of heated fluid;

a heating element associated with said base for heating the fluid within said reservoir;

a controller for controlling said heating element and maintaining the temperature of the heated fluid within said reservoir, said controller being located at a remote location from said bowl.

37. The portable bowl as set forth in claim 36, including a retractable cover assembly for keeping the heated fluid within the bowl and to assist in keeping the fluid at a pre-determined temperature.

38. The portable bowl as set forth in claim 36, wherein said cover assembly includes features for holding tools to allow the tools to extend into the heated fluid within said portable bowl when placed therein.

39. The portable bowl as set forth in claim 37, wherein said cover assembly includes a contoured lip for receiving an apparatus while fluid heats the apparatus for applying the heated fluid to a localized portion of a bioabsorbable plate to allow the apparatus to rest within said bowl when not in use.

41. The container as set forth in claim 39, wherein said tray includes a plurality of apertures spaced radially about said tray, each said aperture adapted to removably hold one fastener in vertical orientation.

43. The container as set forth in claim 41, wherein said tray includes a plurality of detents spaced radially around the outer circumference of said tray, said lid including at least one indent for receiving one of said plurality of detents, whereby said lid can be rotated between a plurality of radial positions.

45. The container as set forth in claim 39, wherein said container is color coded to contrast the color of the fasteners therein to allow the fasteners to stand out visibly when held within said container.

40. A container for holding and delivering fasteners, said container comprising;

a tray for holding at least one fastener;

a lid mounted rotatably onto said tray to keep the fasteners in said tray, and including at least one opening to allow the fasteners to be removed from said tray.

42. The container as set forth in claim 40, wherein said lid includes a first opening and a second opening spaced to fall directly above said apertures when said lid is rotated and adapted to allow an operable end of a driver to be inserted into said tray to engage and remove the fastener from one of said apertures.

44. The container as set forth in claim 42, wherein said detents are spaced such that as said lid rotates, said pair of openings within said lid move from a first position where said first opening is directly over one of said apertures and said second opening is positioned between two of said apertures, a second position where both said first and second openings are located directly above one of said apertures, and a third position where both said first and second openings are located between two of said apertures.

46. A device for handling bioabsorbable osteosynthesis plates, said device comprising;

a pair of flexible elongated arms in adjacent lengthwise relationship with one another, each member having a first end and a second end, said first ends of said arms being secured to one another, wherein said second ends of said arms are disposed at a distance from one another;

a generally flat protruding portion attached to said second end of each of said arms, said protruding portion of each arm being oriented parallel to one another.

47. The device as set forth in claim 46, wherein each of said arms include a handle portion extending from said first end providing a gripping surface for holding said device and for squeezing said arms toward one another to bring said protruding portions into contact with one another.

48. The device as set forth in claim 46, wherein each of said arms includes a neck portion extending from said handle portion, said protruding portions being attached to said neck portions at a distal end opposite said handle portion.

49. The device as set forth in claim 47, wherein said neck portion extends from said handle portion at an angle which is less than 180 degrees.

50. A template for capturing the contour of a bone structure to be repaired to allow a bioabsorbable osteosynthesis plate to be pre-contoured, wherein said template presents a two-dimensional shape that roughly corresponds to the two-dimensional shape of the plate that is to be contoured;

said template includes an identification mark designating the size and shape of said template, said identification mark matching an identification mark placed on corresponding plates.

51. The template as set forth in claim 50, including indents along the edges of said template corresponding to the locations of fastener openings within the plate.

52. The template as set forth in claim 50, wherein said template is made from a malleable material which is autoclavable to allow said template to be sterilized and re-used.

53. A template for capturing the contour of a bone structure to be repaired to allow a bioabsorbable plate to be pre-contoured comprising;

a block having a top and bottom surface, and including a plurality of through holes extending between said top and bottom surfaces;

a plurality of pins having a first end and a second end, one of said plurality of pins being disposed within each of said through holes and including a head portion on each of said first and second ends, said head portion being sized larger than said through holes to retain said pins within said block, said pins having a length that is greater than the thickness of said block to allow said pins to slide within said through holes;

a locking device for locking said pins within said through holes to prevent said pins from sliding therein.

54. The alternative template as set forth in claim 53, wherein said block is formed from a compressible material, and said locking device is a clamping mechanism operative to squeeze said block to compress said through holes to prevent said pins from sliding therein.

55. A drill bit tool for simultaneously drilling and tapping a hole within a bone structure to be repaired for receiving a fastener to attach a bioabsorbable plate to the bone structure;

tool includes helical cutting flutes to facilitate efficient removal of bone chips when said drill bit tool is being used.

56. A kit for delivering items related to surgically repairing a bone structure using bioabsorbable plates, said kit comprising:

a plurality of various shapes and sizes of bioabsorbable plates;

a plurality of fasteners for attaching said plates to a bone structure to be repaired;

a portable bowl for containing and heating a volume of fluid for heating said bioabsorbable plates;

an apparatus for heating a localized portion of said bioabsorbable plate;

a device for handling said bioabsorbable plates;

a drill bit tool for simultaneously drilling and tapping holes within the bone structure for application of said bioabsorbable plates;

a driver for retrieving said fasteners from said containers and threading said fasteners into the bone structure to secure said bioabsorbable plates thereto.

57. A method of repairing broken bone including the steps of;

providing a bioabsorbable plate having a first thermo-chemical solid state which is rigid, and a second thermo-chemical solid state which is moldable;

inserting the plate within a source of heated fluid to heat the plate to the moldable thermo-chemical solid state;

forming the plate to a desired contour;

allowing the plate to cool to the rigid thermo-chemical solid state;

placing the plate to the bone structure to be repaired; and

fastening the plate to the bone structure;

providing a fastener for attaching the plates to the bone structure, a container for delivering the fasteners to a point of use including a base portion with apertures for holding a plurality of fasteners, and a lid portion with at least one opening therein, and a driver for threading the fasteners into the bone structure;

rotating the lid of the container until the opening is positioned directly over an aperture with a fastener held therein;

inserting the driver through the opening in the lid and into the container to engage the fastener held within the aperture;

withdrawing the driver from the container with the fastener held thereto;

applying the fastener to the bone structure and threading the fastener into the bone structure by rotating the driver; and

removing the driver from the fastener after the fastener has been threaded into the bone structure.

58. A method of repairing broken bone including the steps of:

providing a bioabsorbable plate having a first thermo-chemical solid state which is rigid, and a second thermo-chemical solid state which is moldable;

inserting the plate within a source of heated fluid to heat the plate to the moldable thermo-chemical solid state;

forming the plate to a desired contour;

allowing the plate to cool to the rigid thermo-chemical solid state;

placing the plate to the bone structure to be repaired; and

fastening the plate to the bone structure;

providing a drill bit tool for drilling and tapping a hole for receiving a fastener into the bone structure to be repaired; and

placing the drill bit tool to the bone structure and forming a tapped hole in the bone structure prior to applying the plate, applying the plate to the bone structure and driving the fastener into the bone by using the driver.

59. A method of repairing broken bone including the steps of:

providing a template for pre-shaping a bioabsorbable plate;

placing the template to the bone structure and molding the template to the contour of the bone structure;

removing the template from the bone structure; and

placing the heated plate to the template and molding the plate to the contour of the template.

60. A method of repairing broken bone including the steps of:

providing a bioabsorbable plate having a first thermo-chemical solid state which is rigid, and a second thermo-chemical solid state which is moldable;

inserting the plate within a source of heated fluid to heat the plate to the moldable thermo-chemical solid state;

forming the plate to a desired contour;

allowing the plate to cool to the rigid thermo-chemical solid state;

placing the plate to the bone structure to be repaired; and

fastening the plate to the bone structure;

providing said template with an identification mark designating the size and shape of the template, and providing the bioabsorbable plate with an identification mark designating the size and shape of the plate, and the markings on corresponding templates and plates match, the method further including the steps of;

reading the identification mark from the template after the template has been contoured to the bone structure; and

selecting a plate which has an identification mark that matches the identification mark read from the template.

61. A method of repairing broken bone comprising:

providing a device for localized heating of the plates;

inserting the device into a volume of heated fluid;

bringing the device into close proximity to the plate;

heating the localized portion of the plate; and

molding the plate to more closely match the contour of the bone structure to be repaired.

62. A method of repairing broken bone including the steps of:

providing a bioabsorbable plate having a first thermo-chemical solid state which is rigid, and a second thermo-chemical solid state which is moldable;

inserting the plate within a source of heated fluid to heat the plate to the moldable thermo-chemical solid state;

forming the plate to a desired contour;

allowing the plate to cool to the rigid thermo-chemical solid state;

placing the plate to the bone structure to be repaired; and

fastening the plate to the bone structure;

handling the plates with a handling device, wherein the handling device includes a pair of flexible elongated arms in adjacent lengthwise relationship with one another, each arm having a first end and a second end, the first ends of the arms being secured to one another, the second ends of the arms are disposed at a distance from one another and include a generally flat protruding portion, the protruding portions of each arm being oriented parallel to one another; and

grasping the plates with the protruding portions.