Minimally invasive interspinous process spacer implants and methods
An interspinous process spacer for implantation in an interspinous space between a superior spinous process and an inferior spinous process includes a balloon-like body, a first deployable protrusion and a second deployable protrusion. The body has a distal end, a proximal end and a longitudinal axis extending between the proximal and distal ends. The spacer is arrangeable in an unexpanded configuration and an expanded configuration. The first deployable protrusion is mounted proximate the proximal end and the second deployable protrusion is mounted proximate the distal end. The first and second deployable protrusions are oriented generally parallel to the longitudinal axis in the unexpanded configuration and generally perpendicular to the longitudinal axis in the expanded configuration.
1. A spinal implant for implantation in an interspinous space between a superior spinous process and an inferior spinous process, the spinal implant comprising:
a balloon-like body having a distal end, a proximal end, and a longitudinal axis extending between the proximal and distal ends, the balloon-like body being arrangeable in an unexpanded configuration and an expanded configuration;
an exterior member disposed proximate a superior surface of the balloon-like body, the exterior member including a first deployable protrusion mounted proximate the proximal end, and a second deployable protrusion mounted proximate the distal end, the first and second deployable protrusions having an increasing thickness from their ends towards the longitudinal axis, the increasing thickness present in both the unexpanded and expanded configurations,
wherein an outer surface of each of the first and second deployable protrusions is oriented generally parallel to the longitudinal axis in the unexpanded configuration and transverse to the longitudinal axis in the expanded configuration.
2. The spinal implant of claim 1 wherein the balloon-like body comprises:
an inflatable interior member; and
the exterior member disposed around a portion of the inflatable interior member.
3. The spinal implant of claim 2 wherein the exterior member is formed from one of a compliant material or a semi-compliant material, and wherein the interior member is formed from one of compliant material or non-compliant material.
4. The spinal implant of claim 2 wherein the exterior member is inflatable such that inflating the exterior member also inflates the first deployable protrusion and the second deployable protrusion.
5. The spinal implant of claim 1 further comprising:
the exterior member comprising:
a relatively solid member disposed on a surface of the balloon-like body;
a first bendable portion distally adjacent to the relatively solid member and adjacent to the first deployable protrusion, the bendable portion acting as a hinge between the relatively solid member and the first deployable protrusion; and
a second bendable portion proximally adjacent to the relatively solid member and adjacent to the second deployable protrusion, the bendable portion acting as a hinge between the relatively solid member and the second deployable protrusion.
6. The spinal implant of claim 5 wherein the exterior member defines a reduced thickness portion extending between the first bendable portion and the second bendable portion, the reduced thickness portion having a thickness less than the increased thickness portions of the first and second deployable protrusions.
7. The spinal implant of claim 1 wherein at least one deployable protrusion is relatively rigid in the expanded configuration.
8. The spinal implant of claim 1 wherein the first deployable protrusion and the second deployable protrusion pinch inwardly when expanded.
9. The spinal implant of claim 1 wherein an inflatable component is inflated with a biocompatible fluid or biocompatible gas, wherein the inflatable component comprises at least one from among a group consisting of the balloon-like body, the first deployable protrusion, and the second deployable protrusion.
10. The spinal implant of claim 1 wherein at least one deployable protrusion is formed from solid material.
11. The spinal implant of claim 1 further comprising:
a second exterior member disposed proximate an inferior surface of the balloon-like body, the second exterior member including a third deployable protrusion mounted proximate the proximal end and generally opposite the first deployable protrusion; and
a fourth deployable protrusion mounted proximate the distal end and generally opposite the second deployable protrusion,
wherein an outer surface of each of the third and fourth deployable protrusions is oriented generally parallel to the longitudinal axis in the unexpanded configuration and transverse to the longitudinal axis in the expanded configuration.
12. The spinal implant of claim 1 wherein the increased thickness portions of first and second deployable protrusions deflect the balloon-like body in the unexpanded configuration.
13. The spinal implant of claim 1 wherein the increased thickness portions of first and second deployable protrusions are contacted by the balloon-like body during movement to the expanded configuration to rotate the first and second deployable protrusions to the expanded configuration.
14. A method of implanting an inflatable spinal implant having deployable securing elements into an interspinous space between a superior spinous process and an inferior spinous process, the method comprising:
inserting a guiding device into an interspinous ligament in the interspinous space;
introducing the spinal implant via the guiding device into the interspinous space, the spinal implant comprising:
a balloon-like body having a distal end, a proximal end, and a longitudinal axis extending between the proximal and distal ends, the balloon-like body being arrangeable in an unexpanded configuration and an expanded configuration;
an exterior member disposed proximate a superior surface of the balloon-like body, the exterior member including the deployable securing elements including a first deployable protrusion mounted proximate the proximal end, and a second deployable protrusion mounted proximate the distal end, the first and second deployable protrusions having an increasing thickness from their ends towards the longitudinal axis, the increasing thickness present in both the unexpanded and expanded configurations, an outer surface of each of the first and second deployable protrusions is oriented generally parallel to the longitudinal axis in the unexpanded configuration and transverse to the longitudinal axis in the expanded configuration;
inflating the spinal implant such that a first portion of the spinal implant is positioned contralaterally of the interspinous space and a second portion of the spinal implant is positioned ipsilaterally of the interspinous space; and
deploying the deployable securing elements.
15. The method of claim 14 wherein the guiding device is a cannula, and wherein the spinal implant is introduced into the interspinous space utilizing the cannula.
16. The method of claim 15 wherein the cannula is utilized to inflate the spinal implant.
17. The method of claim 14 wherein the inflatable spinal implant comprises:
a balloon-like body having a distal end, a proximal end, and a longitudinal axis extending between the proximal and distal ends, the balloon-like body being arrangeable in an unexpanded configuration and an expanded configuration;
a first deployable protrusion mounted proximate the proximal end; and
a second deployable protrusion mounted proximate the distal end,
wherein the first and second deployable protrusions are oriented generally parallel to the longitudinal axis in the unexpanded configuration and generally perpendicular to the longitudinal axis in the expanded configuration.