SPINE DISTRACTION IMPLANT AND METHOD
A spine distraction implant alleviates pain associated with spinal stenosis and facet arthropathy by expanding the volume in the spine canal and/or neural foramen. The implant provides a spinal extension stop while allowing freedom of spinal flexion.
1 . An apparatus, comprising:
an implant configured to access a space between adjacent spinous processes from a first side of the adjacent spinous processes, a central portion of the implant being disposed between a first arm of the implant and a second arm of the implant,
the central portion of the implant configured to be positioned between the adjacent spinous processes such that the implant can move relative to adjacent spinous processes,
the first arm and the second arm collectively limiting movement of the implant in a direction substantially normal to a longitudinal axis of the central portion when positioned between the adjacent spinous processes.
2 . The apparatus of claim 1 , wherein:
the first arm has a dimension along an axis normal to the longitudinal axis greater than a dimension of the central portion along the axis normal to the longitudinal axis,
the second arm has a dimension along the axis normal to the longitudinal axis greater than the dimension of the central portion along the axis normal to the longitudinal axis.
3 . The apparatus of claim 1 , wherein:
the adjacent spinous processes are included within a spinal column,
the central portion of the implant is configured to be positioned between the adjacent spinous processes such that the implant can move with respect to extension of the spinal column.
4 . The apparatus of claim 1 , wherein:
the adjacent spinous processes are included within a spinal column,
the central portion of the implant is configured to be positioned between the adjacent spinous processes such that the implant can move with respect to extension of the spinal column and with respect to a lateral motion substantially parallel to the longitudinal axis.
5 . The apparatus of claim 1 , wherein:
the central portion is configured to be positioned between the adjacent spinous processes such that the central portion of the implant remains between the adjacent spinous processes without the implant being connected to at least one adjacent spinous processes.
6 . The apparatus of claim 1 , wherein:
the adjacent spinous processes are included within a spinal column, and
the central portion is configured to be positioned between the adjacent spinous processes such that the central portion is maintained within a space between the adjacent spinous processes during extension and flexion of the spinal column without at least a portion of the implant surrounding at least one adjacent spinous processes.
7 . An apparatus, comprising:
an implant having a distal end portion, a proximal end portion and a central portion located between the distal end portion and the proximal end portion, the proximal end portion configured to access a space between adjacent spinous processes of a spinal column from a first side of the adjacent spinous processes,
the central portion of the implant configured to be positioned between, without altering, the adjacent spinous processes, the central portion of the implant configured to limit extension of the spinal column,
the distal end portion including a first arm configured to allow flexion of the spinal column and limit relative motion between the implant and the adjacent spinous processes in a lateral direction.
8 . The apparatus of claim 7 , wherein:
the implant defines a longitudinal axis, the central portion of the implant having a dimension along an axis transverse of the longitudinal axis, the first arm of the implant having a dimension along the axis greater than the dimension of the central portion of the implant.
9 . The apparatus of claim 7 , wherein:
the implant defines a longitudinal axis, the central portion of the implant having a dimension along an axis transverse of the longitudinal axis, the first arm of the implant having a dimension along the axis greater than a maximum distance between the adjacent spinous processes during flexion of the spinal column.
10 . The apparatus of claim 7 , wherein:
the implant defines a longitudinal axis, the central portion of the implant having a dimension along an axis transverse of the longitudinal axis, the first arm of the implant having a dimension along the axis greater than the dimension of the central portion of the implant,
the distal end portion has a second arm, and
the second arm of the implant has a dimension along the axis greater than the dimension of the central portion of the implant.
11 . The apparatus of claim 7 , wherein:
the lateral direction is a first direction,
the distal end portion has a second arm, and
the second arm configured to allow flexion of the spinal column and to limit relative motion between the implant and the adjacent spinous processes in a second lateral direction opposite the first lateral direction.
12 . The apparatus of claim 7 , wherein:
the adjacent spinous processes include a first spinous process and a second spinous process,
a distance between the central portion of the implant and the first spinous process when the spinal column is extended is less than a distance between the central portion of the implant and the first spinous process when the spinal column is flexed, and
a distance between the central portion of the implant and the second spinous process when the spinal column is extend is less than a distance between the central portion of the implant and the second spinous process when the spinal column is flexed.
13 . The apparatus of claim 7 , wherein:
the proximal end portion is configured to access a space between adjacent spinous processes of a spinal column such that the supraspinous ligament is intact; and
the central portion is configured to be positioned between the adjacent spinous processes such that the supraspinous ligament is intact.
14 . The apparatus of claim 7 , wherein:
the central portion is configured to be positioned between the adjacent spinous processes such that the central portion of the implant remains within the space between the adjacent spinous processes without the implant being connected to at least one adjacent spinous processes.
15 . An apparatus, comprising:
an implant configured to access a space between adjacent spinous processes from a first side of the adjacent spinous processes,
the implant having a central portion configured to be positioned between, without altering, the adjacent spinous processes such that the implant has a range of motion relative to adjacent spinous processes, the central portion of the implant limiting a first portion of the range of motion,
a first end portion and a second end portion of the implant collectively limiting a second portion of the range of motion substantially normal to the first portion of the range of motion.
16 . The apparatus of claim 15 , wherein:
the implant has a longitudinal axis,
the first end portion includes an arm having a dimension along an axis normal to the longitudinal axis greater than a dimension of the central portion along the axis normal to the longitudinal axis,
the second end portion including an arm having a dimension along the axis normal to the longitudinal axis greater than the dimension of the central portion along the axis normal to the longitudinal axis.
17 . The apparatus of claim 15 , wherein:
the adjacent spinous processes are included within a spinal column,
the first portion of the range of motion is associated with extension of the spinal column.
18 . The apparatus of claim 15 , wherein:
the implant has a longitudinal axis,
the second portion of the range of motion is associated with a lateral motion substantially parallel to the longitudinal axis.
19 . The apparatus of claim 15 , wherein:
the implant has a longitudinal axis,
the adjacent spinous processes are included within a spinal column,
a first portion of the range of motion is associated with extension of the spinal column,
a second portion of the range of motion is associated with a lateral motion substantially parallel to the longitudinal axis.
20 . The apparatus of claim 15 , wherein:
the central portion is configured to be positioned between the adjacent spinous processes such that the central portion of the implant remains between the adjacent spinous processes without the implant being connected to at least one adjacent spinous processes.
21 . The apparatus of claim 15 , wherein:
the adjacent spinous processes are included within a spinal column, and
the central portion is configured to be positioned between the adjacent spinous processes such that the central portion is maintained within a space between the adjacent spinous processes during extension and flexion of the spinal column without at least a portion of the implant surrounding at least one adjacent spinous processes.