Percutaneous spinal implants and methods

Abstract

An apparatus includes a support member and a retention member. The support member has at least a portion configured to be disposed between a first spinous process and a second spinous process. The retention member is movably coupled to an end portion of the support member. The retention member is configured to displace a bodily tissue. The retention member is configured to move relative to the support member from a first position to a second position. The retention member is configured to limit movement of the support member along the longitudinal axis and relative to the first spinous process and the second spinous process when in the second position.

1 . An apparatus comprising: 
 a first member having a first surface and a second surface, the second surface offset from a longitudinal axis of the first member by a non-zero angle, at least a portion of the first surface configured to engage a spinous process; and    a second member rotatably coupled to a distal end of the first member, the second member configured to move relative to the first member between a first position and a second position, at least a portion of a surface of the second member being disposed adjacent at least a portion of the second surface of the first member when the second member is in the first position,    the portion of the surface of the second member being disposed apart from the portion of the second surface of the first member when the second member is in the second position, the portion of the surface of the second member configured to limit movement of the first member along the longitudinal axis and relative to the spinous process when the second member is in the second position.    
     
     
         2 . The apparatus of  claim 1 , wherein the first surface of the first member is substantially parallel to the longitudinal axis of the first member.  
     
     
         3 . The apparatus of  claim 1 , wherein the surface of the second member is substantially parallel to the second surface of the first member.  
     
     
         4 . The apparatus of  claim 1 , wherein the second surface of the first member is disposed at the distal end of the first member.  
     
     
         5 . The apparatus of  claim 1 , wherein the surface of the second member is in contact with the portion of the second surface of the first member when the second member is in the first position.  
     
     
         6 . The apparatus of  claim 1 , wherein the portion of the surface of the second member is configured to engage the spinous process to limit movement of the first member along the longitudinal axis and relative to the spinous process.  
     
     
         7 . The apparatus of  claim 1 , wherein the second member is configured to rotate relative to the first member from the first position to the second position about an axis substantially parallel to the longitudinal axis of the first member.  
     
     
         8 . The apparatus of  claim 1 , wherein: 
 the spinous process is a first spinous process;    the first member and the second member are configured to be inserted percutaneously such that the portion of the first surface of the first member is between the first spinous process and a second spinous process; and    the second member is configured to move from the first position to the second position after the at least the portion of the first member is disposed between the first spinous process and the second spinous process.    
     
     
         9 . The apparatus of  claim 1 , wherein: 
 the second surface of the first member has an area; and    the surface of the second member has an area,    the area of the surface of the second member being within the area of the second surface of the first member when projected on a plane substantially normal to the longitudinal axis and when the second member is in the first position,    a portion of the area of the surface of the second member being outside of the area of the second surface of the first member when projected on the plane substantially normal to the longitudinal axis and when the second member is in the second position.    
     
     
         10 . The apparatus of  claim 1 , wherein a portion of the surface of the second member and a portion of the first surface of the first member collectively form a portion of a saddle configured to receive a portion of the spinous process when the second member is in the second position.  
     
     
         11 . The apparatus of  claim 1 , wherein the surface of the second member is a first surface, the second member including a second surface substantially parallel to the first surface of the first member, the apparatus further comprising: 
 a locking member disposed within the first member and configured to engage the first surface of the second member when the second member is in the first position,    at least a portion of the locking member disposed outside of the first member and configured to engage the second surface of the second member when the second member is in the second position; and    a biasing member disposed within the first member, the biasing member configured to bias the locking member such that the portion of the locking member is disposed outside of the first member.    
     
     
         12 . The apparatus of  claim 1 , wherein: 
 the surface of the second member is a first surface; and    the second member includes a second surface having a curved shape asymmetrical about the longitudinal axis.    
     
     
         13 . The apparatus of  claim 1 , wherein: 
 the surface of the second member is a first surface; and    the second member includes a second surface configured to dilate a bodily tissue.    
     
     
         14 . The apparatus of  claim 1 , wherein: 
 the surface of the second member is a first surface; and    the second member includes a second surface configured to distract a space between the spinous process and an adjacent spinous process.    
     
     
         15 . An apparatus, comprising: 
 a support member having at least a portion configured to be disposed between a first spinous process and a second spinous process; and    a retention member movably coupled to an end portion of the support member, the retention member configured to displace a bodily tissue, the retention member configured to move relative to the support member from a first position to a second position, the retention member configured to limit movement of the support member along a longitudinal axis of the support member and relative to the first spinous process and the second spinous process when in the second position.    
     
     
         16 . The apparatus of  claim 15 , wherein the retention member is configured to rotate about an axis substantially parallel to a longitudinal axis of the support member.  
     
     
         17 . The apparatus of  claim 15 , wherein: 
 a portion of the retention member is disposed within the support member when the retention member is in the first position; and    the portion of the retention member is disposed outside of the support member when the retention member is in the second position.    
     
     
         18 . The apparatus of  claim 15 , wherein: 
 the end portion of the support member has a cross-sectional area normal to the longitudinal axis of the support member; and    the retention member has a cross-sectional area normal to the longitudinal axis of the support member,    the cross-sectional area of the retention member being within the cross-sectional area of the end portion of the support member when projected on a plane substantially normal to the longitudinal axis and when the retention member is in the first position,    a portion of the cross-sectional area of the retention member being outside of the cross-sectional area of the end portion of the support member when projected on the plane substantially normal to the longitudinal axis and when the retention member is in the second position.    
     
     
         19 . The apparatus of  claim 15 , wherein: 
 the support member and the retention member are configured to be inserted between the first spinous process and the second spinous process percutaneously; and    the retention member is configured to move from the first position to the second position after the support member is disposed between the first spinous process and the second spinous process.    
     
     
         20 . The apparatus of  claim 15 , wherein the support member and the retention member are configured to be inserted between the first spinous process and the second spinous process percutaneously in a direction along the longitudinal axis of the support member.  
     
     
         21 . The apparatus of  claim 15 , wherein: 
 the support member is tapered such that a size of a distal end portion of the support member along an axis substantially normal to the longitudinal axis is less than a size of a proximal end portion of the support member along the axis substantially normal to the longitudinal axis; and    the retention member is movably coupled to the distal end portion of the support member.    
     
     
         22 . The apparatus of  claim 15 , wherein a portion of the retention member and a portion of the support member collectively form a portion of a saddle configured to receive a portion of the first spinous process when the retention member is in the second position.  
     
     
         23 . The apparatus of  claim 15 , wherein the portion of the support member is configured to engage the first spinous process and the second spinous process upon spinal extension.  
     
     
         24 . The apparatus of  claim 15 , wherein the retention member is configured to repeatedly move between the first position and the second position.  
     
     
         25 . The apparatus of  claim 15 , wherein the retention member is a first retention member and the end portion of the support member is a distal end portion, the apparatus further comprising: 
 a second retention member movably coupled to a proximal end portion of the support member, the second retention member configured to rotate relative to the support member from a first position to a second position about the axis substantially parallel to the longitudinal axis of the support member, the second retention member configured to limit movement of the support member along the longitudinal axis and relative to the first spinous process and the second spinous process when in the second position.    
     
     
         26 . The apparatus of  claim 15 , further comprising a locking member configured to releasably maintain the retention member in the second position.  
     
     
         27 . The apparatus of  claim 15 , further comprising: 
 a locking member disposed within the support member and configured to engage a first surface of the retention member when the retention member is in the first position such that the retention member is maintained in the first position,    at least a portion of the locking member disposed outside of the support member and configured to engage a second surface of the retention member when the retention member is in the second position such that the retention member is maintained in the second position, the second surface different than the first surface.    
     
     
         28 . The apparatus of  claim 15 , further comprising: 
 a locking member disposed within the support member and configured to engage a first surface of the retention member when the retention member is in the first position such that the retention member is maintained in the first position,    at least a portion of the locking member disposed outside of the support member and configured to engage a second surface of the retention member when the retention member is in the second position such that the retention member is maintained in the second position, the second surface different than the first surface; and    a biasing member disposed within the support member, the biasing member configured to bias the locking member in a direction such that the at least the portion of the locking member is disposed outside of the support member.    
     
     
         29 . The apparatus of  claim 15 , wherein the retention member has an outer surface that is curved asymmetrically about the longitudinal axis.  
     
     
         30 . The apparatus of  claim 15 , wherein the retention member has a tapered end portion configured to dilate the bodily tissue.  
     
     
         31 . the apparatus of  claim 15 , wherein the retention member is configured to distract a space between the first spinous process and the second spinous process.  
     
     
         32 . An apparatus comprising: 
 a support member having at least a portion configured to engage adjacent spinous processes, a distal end of the support member having a cross-sectional area normal to a longitudinal axis of the support member; and    a retention member rotatably coupled to the distal end of the support member, the retention member having a cross-sectional area normal to the longitudinal axis of the support member, the retention member configured to rotate relative to the support member about an axis substantially parallel to the longitudinal axis of the support member from a first position to a second position, the retention member configured to limit movement of the support member along the longitudinal axis and relative to the first spinous process and the second spinous process when in the second position,    the cross-sectional area of the retention member being within the cross-sectional area of the distal end of the support member when projected on a plane substantially normal to the longitudinal axis and when the retention member is in the first position,    a portion of the cross-sectional area of the retention member being outside of the cross-sectional area of the distal end of the support member when projected on the plane substantially normal to the longitudinal axis and when the retention member is in the second position.    
     
     
         33 . The apparatus of  claim 32 , wherein: 
 the support member and the retention member are configured to be inserted between the first spinous process and the second spinous process percutaneously; and    the retention member is configured to rotate from the first position to the second position after the support member is disposed between the first spinous process and the second spinous process.    
     
     
         34 . The apparatus of  claim 32 , wherein the support member is tapered such that a size of the distal end portion of the support member along an axis substantially normal to the longitudinal axis is less than a size of a proximal end portion of the support member along the axis substantially normal to the longitudinal axis.  
     
     
         35 . The apparatus of  claim 32 , wherein a portion of the retention member and a portion of the support member collectively form a portion of a saddle configured to receive the first spinous process when the retention member is in the second position.  
     
     
         36 . The apparatus of  claim 32 , wherein: 
 a proximal end of the retention member is coupled to the distal end of the support member; and    the cross-sectional area of the retention member is coincident with the proximal end of the retention member.    
     
     
         37 . The apparatus of  claim 32 , wherein the retention member is configured to repeatedly move between the first position and the second position.  
     
     
         38 . The apparatus of  claim 32 , wherein the retention member is a first retention member, the apparatus further comprising: 
 a second retention member rotatably coupled to a proximal end portion of the support member, the second retention member configured to rotate relative to the support member from a first position to a second position about an axis substantially parallel to the longitudinal axis of the support member, the second retention member configured to limit movement of the support member along the longitudinal axis and relative to the first spinous process and the second spinous process when in the second position.    
     
     
         39 . The apparatus of  claim 32 , further comprising a locking member configured to reversibly maintain the retention member in the second position.  
     
     
         40 . The apparatus of  claim 32 , further comprising: 
 a locking member disposed within the support member and configured to engage a proximal surface of the retention member when the retention member is in the first position such that the retention member is maintained in the first position,    at least a portion of the locking member disposed outside of the support member and configured to engage an outer surface of the retention member when the retention member is in the second position such that the retention member is maintained in the second position; and    a biasing member disposed within the support member, the biasing member configured to bias the locking member in a direction such that the at least the portion of the locking member is disposed outside of the support member.    
     
     
         41 . An apparatus comprising: 
 a support member having at least a portion configured to engage adjacent spinous processes, a distal end of the support member having a first dimension along a first axis substantially normal to a longitudinal axis of the support member and a second dimension along a second axis, the second axis being substantially normal to the longitudinal axis and the first axis, the second dimension greater than the first dimension; and    a retention member movably coupled to the distal end of the support member, the retention member configured to displace a bodily tissue, the retention member configured to move relative to the support member from a first position to a second position,    the retention member having a first dimension along the first axis and a second dimension along the second axis, the first dimension of the retention member being greater than the second dimension of the support member and no greater than the first dimension of the support member, the second dimension of the retention member being no greater than the second dimension of the support member.    
     
     
         42 . The apparatus of  claim 41 , wherein the retention member is configured to rotate relative to the support member from the first position to the second position about an axis substantially parallel to the longitudinal axis of the support member.  
     
     
         43 . The apparatus of  claim 41 , wherein: 
 the first dimension of the retention member is aligned with the first dimension of the support member when the retention member is in the first position; and    the first dimension of the retention member is aligned with the second dimension of the support member when the retention member is in the second position.    
     
     
         44 . The apparatus of  claim 41 , wherein: 
 the first dimension of the retention member is substantially equal to the first dimension of the support member; and    the second dimension of the retention member is substantially equal to the second dimension of the support member.    
     
     
         45 . The apparatus of  claim 41 , wherein the retention member is configured to repeatedly move between the first position and the second position.  
     
     
         46 . The apparatus of  claim 41 , wherein the retention member is a first retention member, the apparatus further comprising: 
 a second retention member movably coupled to a proximal end portion of the support member, the second retention member configured to rotate relative to the support member from a first position to a second position about an axis substantially parallel to the longitudinal axis of the support member, the second retention member configured to limit movement of the support member along the longitudinal axis and relative to the first spinous process and the second spinous process when in the second position.    
     
     
         47 . The apparatus of  claim 41 , further comprising: 
 a locking member disposed within the support member and configured to engage a proximal surface of the retention member when the retention member is in the first position such that the retention member is maintained in the first position,    at least a portion of the locking member disposed outside of the support member and configured to engage an outer surface of the retention member when the retention member is in the second position such that the retention member is maintained in the second position; and    a biasing member disposed within the support member, the biasing member configured to bias the locking member in a direction such that the at least the portion of the locking member is disposed outside of the support member.    
     
     
         48 . The apparatus of  claim 41 , wherein the retention member has a tapered end portion configured to dilate the bodily tissue.  
     
     
         49 . the apparatus of  claim 41 , wherein the retention member is configured to distract a space between the first spinous process and the second spinous process.  
     
     
         50 . An apparatus comprising: 
 a support member configured to be disposed between a first spinous process and a second spinous process;    a retention member movably coupled to a distal end of the support member, the retention member configured to move from a first position to a second position to limit movement of the support member along a longitudinal axis and relative to the first spinous process and the second spinous process; and    a locking member disposed within the support member and configured to engage a first surface of the retention member when the retention member is in the first position such that the retention member is maintained in the first position,    at least a portion of the locking member disposed outside of the support member and configured to engage a second surface of the retention member when the retention member is in the second position such that the retention member is maintained in the second position, the second surface different than the first surface.    
     
     
         51 . The apparatus of  claim 50 , wherein the retention member is configured to rotate relative to the support member from the first position to the second position about an axis substantially parallel to the longitudinal axis of the support member.  
     
     
         52 . The apparatus of  claim 50 , wherein: 
 the support member and the retention member are configured to be inserted between the first spinous process and the second spinous process percutaneously; and    the retention member is configured to move from the first position to the second position after the support member is disposed between the first spinous process and the second spinous process.    
     
     
         53 . The apparatus of  claim 50 , wherein: 
 the distal end of the support member has a cross-sectional area normal to a longitudinal axis of the support member; and    the retention member has a cross-sectional area normal to the longitudinal axis of the support member,    the cross-sectional area of the retention member being within the cross-sectional area of the distal end of the support member when projected on a plane substantially normal to the longitudinal axis and when the retention member is in the first position,    a portion of the cross-sectional area of the retention member being outside of the cross-sectional area of the distal end of the support member when projected on the plane substantially normal to the longitudinal axis and when the retention member is in the second position.    
     
     
         54 . The apparatus of  claim 50 , wherein the retention member is configured to repeatedly move between the first position and the second position.  
     
     
         55 . The apparatus of  claim 50 , wherein: 
 the first surface of the retention member includes a recessed portion configured to receive a first portion of the locking member when the retention member is in the first position; and    the second surface of the retention member includes a recessed portion configured to receive a second portion of the locking member when the retention member is in the second position.    
     
     
         56 . The apparatus of  claim 50 , wherein the retention member is a first retention member, the apparatus further comprising: 
 a second retention member movably coupled to a proximal end of the support member, the second retention member configured to rotate relative to the support member from a first position to a second position about an axis substantially parallel to a longitudinal axis of the support member, the second retention member configured to limit movement of the support member along the longitudinal axis and relative to the first spinous process and the second spinous process when in the second position.    
     
     
         57 . The apparatus of  claim 50 , further comprising: 
 a biasing member disposed within the support member, the biasing member configured to bias the locking member in a direction such that the at least the portion of the locking member is disposed outside of the support member.    
     
     
         58 . A method comprising: 
 disposing at least a portion of an implant between adjacent spinous processes, the implant including a support member and a retention member movably coupled to the support member;    rotating the retention member from a first position to a second position such that the retention member retains a portion of the implant between the adjacent spinous processes; and    locking reversibly the retention member in the second position.    
     
     
         59 . The method of  claim 58 , wherein the disposing includes inserting the implant percutaneously via a lateral access path including a portion at the sides of the adjacent spinous processes.  
     
     
         60 . The method of  claim 58 , wherein: 
 the retention member is disposed within the support member when in the first position; and    a portion of the retention member is disposed outside of the support member when in the second position.    
     
     
         61 . The method of  claim 58 , wherein the rotating includes rotating the retention member about an axis substantially parallel to a longitudinal axis of the support member.  
     
     
         62 . The method of  claim 58 , wherein: 
 an end portion of the support member has a cross-sectional area normal to the longitudinal axis of the support member;    the retention member has a cross-sectional area normal to the longitudinal axis of the support member, the cross-sectional area of the retention member being within the cross-sectional area of the distal end of the support member projected on a plane substantially normal to the longitudinal axis and when the retention member is in the first position; and    the rotating includes rotating the retention member such that a portion of the cross-sectional area of the retention member is outside of the cross-sectional area of the distal end of the support member when projected on the plane substantially normal to the longitudinal axis.    
     
     
         63 . The method of  claim 58 , wherein the disposing includes disposing the implant such that a portion of the retention member distracts a space between the adjacent spinous processes.  
     
     
         64 . The method of  claim 58 , further comprising distracting a space between the adjacent spinous processes before the disposing.  
     
     
         65 . An apparatus, comprising: 
 a support member having at least a portion configured to be disposed between a first spinous process and a second spinous process;    a first retention member movably coupled to a first end portion of the support member; and    a second retention member movably coupled to a second end portion of the support member, the second retention member coupled to the first retention member such that the first retention member and the second retention member are configured to collectively move relative to the support member from a first position to a second position, the first retention member and the second retention member configured to limit movement of the support member relative to the first spinous process and the second spinous process when in the second position.    
     
     
         66 . The apparatus of  claim 65 , wherein the first retention member and the second retention member are configured to collectively rotate relative to the support member from the first position to the second position.  
     
     
         67 . The apparatus of  claim 65 , wherein the first retention member and the second retention member are configured to collectively rotate relative to the support member about an axis substantially parallel to the longitudinal axis of the support member.  
     
     
         68 . The apparatus of  claim 65 , wherein 
 the first end portion of the support member has a cross-sectional area normal to the longitudinal axis of the support member;    the first retention member has a cross-sectional area normal to the longitudinal axis of the support member;    the second end portion of the support member has a cross-sectional area normal to the longitudinal axis of the support member; and    the second retention member has a cross-sectional area normal to the longitudinal axis of the support member,    the cross-sectional area of the first retention member being within the cross-sectional area of the first end portion of the support member when projected on a plane substantially normal to the longitudinal axis and when the first retention member is in the first position,    a portion of the cross-sectional area of the first retention member being outside of the cross-sectional area of the first end portion of the support member when projected on the plane substantially normal to the longitudinal axis and when the first retention member is in the second position,    the cross-sectional area of the second retention member being within the cross-sectional area of the second end portion of the support member when projected on a plane substantially normal to the longitudinal axis and when the second retention member is in the first position,    a portion of the cross-sectional area of the second retention member being outside of the cross-sectional area of the second end portion of the support member when projected on the plane substantially normal to the longitudinal axis and when the second retention member is in the second position.    
     
     
         69 . The apparatus of  claim 65 , wherein: 
 the support member, the first retention member and the second retention member are configured to be inserted between the first spinous process and the second spinous process percutaneously; and    the first retention member and the second retention member are configured to collectively move relative to the support member from the first position to the second position after the support member is disposed between the first spinous process and the second spinous process.    
     
     
         70 . The apparatus of  claim 65 , wherein a portion of the support member, a portion of the first retention member and a portion of the second retention member collectively form a portion of a saddle configured to receive a portion of the first spinous process when the first retention member and the second retention member are in the second position.  
     
     
         71 . The apparatus of  claim 65 , wherein the first retention member and the second retention member are configured to repeatedly move between the first position and the second position.  
     
     
         72 . The apparatus of  claim 65 , further comprising a locking member configured to releasably maintain the first retention member and the second retention member in the second position.