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:
a first implant member configured to be disposed within a space between a first spinous process and a second spinous process; and
a second implant member coupled to a proximal end of the first implant member, the second implant member configured to limit lateral movement of the first implant member relative to the first spinous process and the second spinous process,
the first implant member configured rotate relative to the second implant member.
2 . The apparatus of claim 1 , wherein the first implant member has a width and a height greater than the width.
3 . The apparatus of claim 1 , wherein the first implant member has an outer surface that is curved about a longitudinal axis of the first implant member.
4 . The apparatus of claim 1 , wherein the first implant member is configured to rotate relative to the second implant member about a longitudinal axis of the first implant member.
5 . The apparatus of claim 1 , wherein the first implant member is configured to rotate relative to the second implant member when the first implant member is disposed within the space between the first spinous process and the second spinous process.
6 . The apparatus of claim 1 , wherein first implant member is configured to rotate relative to the second implant member about a longitudinal axis of the first implant member by up to sixty degrees.
7 . The apparatus of claim 1 , wherein first implant member is configured to rotate relative to the second implant member about a longitudinal axis of the first implant member by between sixty degrees and one hundred twenty degrees.
8 . The apparatus of claim 1 , wherein first implant member is configured to rotate relative to the second implant member about a longitudinal axis of the first implant member by up to one full revolution.
9 . The apparatus of claim 1 , further comprising:
a third implant member coupled to a distal end of the first implant member, the third implant member configured to limit lateral movement of the first implant member relative to the first spinous process and the second spinous process,
the first implant member configured rotate relative to the third implant member.
10 . The apparatus of claim 1 , wherein the first member includes a tapered end portion configured to displace a bodily tissue.
11 . An apparatus, comprising:
a first implant member having an outer surface and a cross-sectional area within a plane substantially normal to a longitudinal axis of the first implant member; and
a second implant member movably coupled to a proximal end of the first implant member, the first implant member configured rotate relative to the second implant member when at least a portion of the first implant member is disposed within a space between a first spinous process and a second spinous process such that an axis of the first implant member defined to include a maximum dimension of the cross-sectional area is substantially parallel to a center line of the space between the first spinous process and the second spinous process.
12 . The apparatus of claim 11 , wherein the first implant member configured rotate relative to the second implant member such that a longitudinal axis of the second implant member is substantially parallel to a mid-line axis of a spinal column including the first spinous process and the second spinous process.
13 . The apparatus of claim 11 , wherein the outer surface of the first implant member is curved about the longitudinal axis of the first implant member.
14 . The apparatus of claim 11 , wherein the cross-sectional area of the first implant member has an elliptical shape such that the axis of the first implant member includes a major diameter of the cross-sectional area.
15 . The apparatus of claim 11 , wherein a dimension of the second implant member along the longitudinal axis of the second implant member is greater than the maximum dimension of the cross-sectional area of the first implant member.
16 . The apparatus, of claim 11 , wherein:
the first implant member defines an opening along the longitudinal axis of the first implant member; and
the second implant member includes a shaft configured to be disposed within the opening.
17 . The apparatus of claim 11 , wherein the first implant member is configured to rotate relative to the second implant member about the longitudinal axis of the first implant member.
18 . The apparatus of claim 11 , wherein first implant member is configured to rotate relative to the second implant member about a longitudinal axis of the first implant member by up to one hundred twenty degrees.
19 . A method, comprising:
inserting an implant into a space between a first spinous process and a second spinous process, the implant having a support member and a retention member coupled to an end portion of the support member; and
rotating the support member relative to the retention member after the inserting.
20 . The method of claim 19 , wherein the rotating includes rotating the support member about a longitudinal axis of the support member.
21 . The method of claim 19 , wherein the rotating includes rotating the support member about a longitudinal axis of the support member by up to sixty degrees.
22 . The method of claim 19 , wherein the rotating includes rotating the support member about a longitudinal axis of the support member by between sixty degrees and one hundred twenty degrees.
23 . The method of claim 19 , wherein the rotating includes rotating the support member about a longitudinal axis of the support member by up to one full revolution.
24 . The method of claim 19 , wherein the rotating includes rotating the support member such that the support member moves towards an instantaneous axis of rotation of a spinal column.
25 . The method of claim 19 , wherein the rotating includes rotating the support member such that a curved outer surface of the support member contacts an anterior portion of the first spinous process.
26 . The method of claim 19 , wherein:
the support member has a cross-sectional area within a plane substantially normal to a longitudinal axis of the support member; and
the rotating includes rotating the support member such that an axis of the first implant member defined to include a maximum dimension of the cross-sectional area is substantially parallel to a center line of the space between the first spinous process and the second spinous process.
27 . The method of claim 19 , wherein:
the support member has a cross-sectional area within a plane substantially normal to a longitudinal axis of the support member; and
the rotating includes rotating the support member such that an axis of the first implant member defined to include a maximum dimension of the cross-sectional area is substantially parallel to a center line of the space between the first spinous process and the second spinous process and such that a longitudinal axis of the retention member is substantially parallel to a mid-line axis of a spinal column including the first spinous process and the second spinous process.