Collapsible anvil plate assemblies for circular surgical stapling devices

1. An anvil plate for a surgical stapling instrument, said anvil plate comprising:

a plurality of anvil plate segments movably interconnected and reconfigurable from a first orientation wherein said anvil plate segments may be inserted through a cannula opening as a unit and then reconfigured into a second orientation in the form of a substantially planar anvil plate assembly that has a diameter that is larger than a diameter of said cannula opening, wherein said plurality of anvil plate segments are coupled together by a plurality of hinges, wherein said plurality of anvil plate segments comprises four arcuate plate segments coupled by said hinges in end-to-end fashion such that when said four arcuate plate segments are in said first orientation, said four arcuate plate segments may be substantially stacked on top of each other; and

a flexible tether threadably engaging each of said arcuate plate segments such that said arcuate plate segments may be inserted through said cannula opening in an end-to end fashion wherein said arcuate plate segments do not form an annular plate assembly and then drawn together to form said annular plate assembly by applying an actuation motion to said flexible tether to draw a free end of one of said arcuate plate segments into abutting contact with another free end of another of said arcuate plate segments to form said annular plate assembly.

2. An anvil plate for a surgical stapling instrument, said anvil plate comprising:

a plurality of anvil plate segments movably interconnected and reconfigurable from a first orientation wherein said anvil plate segments may be inserted through a cannula opening as a unit wherein at least one of said anvil plate segments is proximal to at least one other of said anvil plate segments and then reconfigured into a second orientation in the form of a substantially planar anvil plate assembly that has a diameter that is larger than a diameter of said cannula opening; and

a flexible tether threadably engaging each of said plurality of anvil plate segments such that said plurality of anvil plate segments may be inserted through said cannula opening in an end-to end fashion wherein said plurality of anvil plate segments do not form an annular plate assembly and then drawn together to form said annular plate assembly by applying an actuation motion to said flexible tether to draw a free end of one of said plurality of anvil plate segments into abutting contact with another free end of another of said plurality of anvil plate segments to form said annular plate assembly.

3. An anvil for a surgical stapling instrument, comprising:

a plurality of anvil plates movably coupled together for selective movement between non-planar orientations and a substantially planar orientation wherein said plurality of anvil plates form an annular anvil plate assembly, wherein said plurality of anvil plates are coupled together by a plurality of hinges, wherein said plurality of anvil plates comprises four arcuate plate segments coupled by said hinges in end-to-end fashion such that when said arcuate plate segments are in a first one of said non-planar orientations, said four arcuate plate segments may be substantially stacked on top of each other and when said arcuate plate segments are in another of said non-planar orientations, two of said arcuate plate segments are stacked on top of another two of said arcuate plate segments;

an anvil support member configured for attachment to said anvil plate assembly to retain said anvil plate assembly in said substantially planar orientation; and

a flexible tether threadably engaging each of said arcuate plate segments such that said arcuate plate segments may be inserted through an opening in an end-to end fashion wherein said arcuate plate segments do not form an annular plate assembly and then drawn together to form said annular plate assembly by applying an actuation motion to said flexible tether to draw a free end of one of said arcuate plate segments into abutting contact with another free end of another of said arcuate plate segments to form said annular plate assembly.

4. An anvil for a surgical stapling instrument, comprising:

a plurality of anvil plates movably coupled together for selective movement between non-planar orientations wherein at least one of said anvil plates is proximal to at least one other of said anvil plates and a substantially planar orientation wherein said plurality of anvil plates form an annular anvil plate assembly;

an anvil support member configured for attachment to said anvil plate assembly to retain said anvil plate assembly in said substantially planar orientation; and

a flexible tether threadably engaging each said anvil plate such that each said anvil plate may be inserted through an opening in an end-to end fashion wherein each said anvil plate does not form an annular plate assembly and then drawn together to form said annular plate assembly by applying an actuation motion to said flexible tether to draw a free end of one of said anvil plates into abutting contact with another free end of another of said anvil plates to form said annular plate assembly.

5. An anvil plate for a surgical stapling instrument, said anvil plate comprising a plurality of anvil plate segments movably interconnected and reconfigurable from a first, non-planar orientation wherein said anvil plate segments may be inserted through a cannula opening as a unit such that at least one of said anvil plate segments is proximal to at least one other of said anvil plate segments and then reconfigured into a second orientation in the form of a substantially planar anvil plate assembly that has a diameter that is larger than a diameter of said cannula opening.

6. The anvil plate of claim 1 wherein said plurality of anvil plate segments are coupled together by a plurality of hinges.

7. The anvil plate of claim 6 wherein said plurality of anvil plate segments comprises four arcuate plate segments coupled by said hinges in end-to-end fashion such that when said four arcuate plate segments are in said first orientation, said four arcuate plate segments may be substantially stacked on top of each other.

8. The anvil plate of claim 1 wherein said plurality of anvil plate segments comprises four arcuate plate segments wherein each said arcuate plate segment has an outer configuration of staple formation pockets and an inner configuration of staple formation pockets that are oriented to form an outer annular ring of staple formation pockets and an inner annular ring of staple formation pockets, respectively when said anvil plate is in said second orientation wherein said staple formation pockets in said inner annular ring of staple formation pockets are staggered from said staple pockets in said outer annular ring of staple formation pockets.

9. The anvil plate of claim 1 wherein said plurality of anvil plate segments are movably coupled together by a plurality of spring clips.

10. The anvil plate of claim 1 wherein each said anvil plate segment comprises an arcuate plate segment having two ends wherein each said end has an attachment joint configured to slidably mate with the attachment joint on an adjacent anvil plate segment when said plurality of anvil plate segments form said anvil plate assembly.

11. The anvil plate of claim 10 wherein each said anvil plate segment has a forming surface and wherein each said attachment joint has an attachment tab portion that is substantially parallel to said forming surface.

12. An anvil for a surgical stapling instrument, comprising:

a plurality of anvil plates movably coupled together for selective movement between non-planar orientations wherein at least one of said plurality of anvil plates is proximal to at least one other of said plurality of anvil plates and a substantially planar orientation wherein said plurality of anvil plates form an annular anvil plate assembly; and

an anvil support member configured for attachment to said anvil plate assembly to retain said anvil plate assembly in said substantially planar orientation.

13. The anvil of claim 12 wherein said plurality of anvil plates are coupled together by a plurality of hinges.

14. The anvil of claim 13 wherein said plurality of anvil plates comprises four arcuate plate segments coupled by said hinges in end-to-end fashion such that when said arcuate plate segments are in a first one of said non-planar orientations, said four arcuate plate segments may be substantially stacked on top of each other and when said arcuate plate segments are in another of said non-planar orientations, two of said arcuate plate segments are stacked on top of another two of said arcuate plate segments.

15. The anvil of claim 12 wherein said plurality of anvil plates comprises four arcuate plate segments wherein each said arcuate plate segment has an outer configuration of staple formation pockets and an inner configuration of staple formation pockets that are oriented to form an outer annular ring of staple formation pockets and an inner annular ring of staple formation pockets, respectively when said annular plate assembly is in said substantially planar orientation wherein said staple formation pockets in said inner annular ring of staple formation pockets are staggered from said staple pockets in said outer annular ring of staple formation pockets.

16. The anvil of claim 12 wherein said plurality of anvil plates are movably coupled together by a plurality of spring clips.

17. The anvil of claim 12 wherein each said anvil plate comprises an arcuate plate segment having two ends wherein each said end has an attachment joint configured to slidably mate with the attachment joint on an adjacent anvil plate when said plurality of anvil plates form said annular anvil plate assembly.

18. The anvil of claim 17 wherein each said anvil plate has a forming surface and wherein each said attachment joint has an attachment tab portion that is substantially parallel to said forming surface.

19. An anvil plate for a surgical stapling instrument, said anvil plate comprising a plurality of anvil plate segments movably interconnected and reconfigurable from a first orientation wherein said anvil plate segments may be inserted through a cannula opening as a unit such that at least one of said anvil plate segments is proximal to at least one other of said anvil plate segments and then reconfigured into a second orientation in the form of a substantially planar anvil plate assembly that has a diameter that is larger than a diameter of said cannula opening, and wherein said plurality of anvil plate segments are supported on a flexible ring member that is configurable between said first orientation and said second orientation.

20. The anvil plate of claim 19 wherein said flexible ring member is fabricated from an elastomeric material and said plurality of anvil plate segments are fabricated from metal material.

21. An anvil for a surgical stapling instrument, comprising:

a plurality of anvil plates movably coupled together for selective movement between non-planar orientations wherein at least one of said anvil plates is proximal to at least one other of said anvil plates and a substantially planar orientation wherein said plurality of anvil plates form an annular anvil plate assembly; and

an anvil support member configured for attachment to said anvil plate assembly to retain said anvil plate assembly in said substantially planar orientation;

wherein said plurality of anvil plates are coupled to a flexible ring member that is configurable between said non-planar orientations and said substantially planar orientation.

22. The anvil of claim 21 wherein said flexible ring member is fabricated from an elastomeric material and said plurality of anvil plates are fabricated from metal material.