1. A method comprising:
consecutively receiving at and writing into a memory a sequence of groupings of bits from a data stream, the groupings of bits having a predetermined size;
reading from the memory a subset of the sequence of the groupings of bits written into the memory, the subset having fewer groupings of bits than the sequence of groupings of bits written into the memory;
applying the subset to a first multiplexer (MUX);
applying another data stream to a third MUX, the another data stream comprising bits representing a virtual local area network (VLAN) tag; and
selectively applying to a second MUX the subset applied to the first MUX and the another data stream applied to the third MUX.
2. The method of claim 1, wherein:
the memory comprises a first in, first out (FIFO) memory; and
the reading is based upon a read pointer generated by a state machine.
3. The method of claim 2, wherein:
the state machine also generates a first MUX select signal, a second MUX select signal, and a third MUX select signal applied to the first MUX, the second MUX, and the third MUX, respectively.
4. An apparatus comprising:
a memory capable of consecutively receiving and storing a sequence of groupings of bits from a data stream, the groupings of bits having a predetermined size, the memory also being capable of retrieving a subset of the sequence of the groupings of bits written into the memory, the subset having fewer groupings of bits than the sequence of groupings of bits written into the memory; and
a first multiplexer (MUX), a second MUX, and a third MUX;
the apparatus being capable of applying the subset to the first MUX, applying another data stream to the third MUX, and selectively applying to a second MUX the subset applied to the first MUX and another data stream applied to the third MUX, the another data stream comprising bits representing a virtual local area network (VLAN) tag.
5. The apparatus of claim 4, wherein:
the memory comprises a first in, first out (FIFO) memory; and the apparatus also comprises a state machine to generate a read pointer, the memory being capable of retrieving the subset based upon the read pointer.
6. The apparatus of claim 5, wherein:
the state machine is also capable of generating a first MUX select signal, a second MUX select signal, and a third MUX select signal to be applied to the first MUX, the second MUX, and the third MUX, respectively.
7. A system comprising:
an integrated circuit comprising:
a memory capable of consecutively receiving and storing a sequence of groupings of bits from a data stream, the groupings of bits having a predetermined size, the memory also being capable of retrieving a subset of the sequence of the groupings of bits written into the memory, the subset having fewer groupings of bits than the sequence of groupings of bits written into the memory; and
a first multiplexer (MUX), a second MUX, and a third MUX;
the integrated circuit being capable of applying the subset to the first MUX, applying another data stream to the third MUX, and selectively applying to the second MUX the subset applied to the first MUX and another data stream applied to the third MUX, the another data stream comprising bits representing a virtual local area network (VLAN) tag.
8. The system of claim 7, further comprising:
an input data bus coupled to the memory.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An expandable spinal stabilization device comprising:
a. a plurality of plates arranged in a stack; and
b. a connecting rod connecting the plurality of plates; wherein the plates are connected to the connecting rod such that the plurality of plates adopt a helical configuration about the longitudinal axis of the connecting rod when the plates are turned about the longitudinal axis of the connecting rod; and further wherein the dimensions of the device render it suitable for insertion into an intervertebral space.
2. The device according to claim 1 wherein the plurality of plates comprise a top plate, a bottom plate, and one or more interstitial plates disposed between the top plate and bottom plate, each plate comprising an obverse face and a reverse face, further wherein the connecting rod extends through the obverse and reverse faces of the top plate and the interstitial plates at a position offset from the geometric center of the plates.
3. The device according to claim 1 wherein the plates are circular.
4. The device according to claim 1 wherein the plates are oval.
5. The device according to claim 1 wherein the circumferential edges of the plates are multi-sided.
6. The device according to claim 5 wherein the plates are square.
7. The device according to claim 5 wherein the plates are star-shaped.
8. The device according to claim 5 wherein the plates are triangular.
9. The device according to claim 1 wherein the circumferential edges of the plates provide sharp cutting edges.
10. The device according to claim 9 wherein the plates are saw-shaped.
11. The device according to claim 1 wherein the plates and the connecting rod are comprised of a biocompatible material.
12. The device according to claim 1 wherein the plates have integrated passages.
13. The device according to claim 1 comprising a top plate, a bottom plate, and one or more interstitial plates disposed between the top plate and the bottom plate, each plate comprising an obverse face and a reverse face such that a pair of adjacent faces comprising the obverse face of one plate and the reverse face of an adjacent plate is provided for each pair of adjacent plates in the stack, wherein:
a. one face in at least one pair of adjacent faces comprises a catch;
b. the other face in the at least one pair of adjacent faces comprises an abutment; and further wherein
c. every abutment is positioned in a manner to engage the catch of an adjacent face when the plates are rotated about the longitudinal axis of the connecting rod.
14. The device according to claim 13 wherein one face in every pair of adjacent faces except the final pair comprises a catch and the other face in every pair of adjacent faces except the final pair comprises an abutment.
15. The device according to claim 13 wherein one face of each pair of adjacent faces comprises a catch and the other face of each pair of adjacent faces comprises an abutment.
16. The device according to claim 13 wherein the reverse face of each pair of adjacent faces comprises an abutment and the obverse face of the at least one pair of adjacent faces comprises a catch.
17. The device according to claim 13 wherein each catch comprises a slot running along the obverse or reverse face of a plate in a direction substantially tangential with respect to the circumference of the connecting rod and each abutment comprises a post extending away from the obverse or reverse face of a plate.
18. The device according to claim 17 wherein the slots are raised from the obverse or reverse faces of the plates.
19. The device according to claim 17 wherein the slots are recessed in the obverse or reverse faces of the plates.
20. The device according to claim 13 wherein the bottom plate is unable to move independently of the connecting rod and the top plate and interstitial plates are connected to the connecting rod in a manner that allows them to rotate about the longitudinal axis of the connecting rod.
21. The device according to claim 20 wherein the obverse face of the top plate comprises a sleeve connector disposed thereon and the connecting rod comprises an end extending beyond the obverse face of the top plate, the device further comprising a turning tool, the turning tool comprising:
a. an outer sleeve having an end adapted to engage the sleeve connector; and
b. an inner sleeve nested within the outer sleeve, the inner sleeve having an end adapted to engage the end of the connecting rod extending beyond the top plate such that when the inner sleeve engages the connecting rod and the outer sleeve engages the sleeve connector, the helical configuration is achieved by turning at least one of the inner and outer sleeves.
22. The device according to claim 21 wherein the sleeve connector is a nut and the end of the outer sleeve is adapted to engage the nut, and further wherein the end of the connecting rod extending beyond the top plate is threaded and the end of the inner sleeve is adapted to engage the threads.
23. A method of stabilizing a spinal column, the method comprising inserting the expandable spinal stabilization device according to claim 1 into an intervertebral space in the spinal column and turning the plates about the longitudinal axis of the connecting rod until the plurality of plates adopt a helical configuration.
24. The method according to claim 23 further comprising inserting a bone growth-promoting material in the intervertebral space around the expandable spinal stabilizing device.
25. The method according to claim 23 wherein the device is inserted using a posterior or posterial lateral approach.
26. The method according to claim 25 wherein the device is inserted with the aid of a tube or cannula.
27. The method according to claim 23 wherein the device is inserted using an anterior approach.