Spine distraction implant and method

Abstract

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.

We claim:  
     
         1 . An implant for relieving pain associated with the spinal column which is positionable between adjacent spinous processes of the spinal column, comprising: 
 a first unit including a guide and a first wing;    a second wing;    said body including a groove that can receive said second wing, said body adapted for positioning between the adjacent spinous processes, with the first wing positionable along side the adjacent spinous processes and the second wing positionable along side the spinous processes and opposite to the first wing; and    a device that secures the second wing to the guide.    
     
     
         2 . The implant of    claim 1    wherein: 
 said first wing has upper and lower portions;  
 said second wing has upper and lower portions;  
 an upper saddle is defined among the body and the upper portions of the first and second wings;  
 a lower saddle is defined among the body and the lower portions of the first and second wing;  
 wherein the upper width of the upper saddle is defined between the upper portions of the first and second wings;  
 wherein the lower width of the lower saddle is defined between the lower portions of the first and second wings;  
 the implant comprising multiple second wings with each second wing having said lower portion of a different thickness; and  
 wherein the lower width can be selected by choosing said second wing with said lower portion of the desired thickness.  
 
     
     
         3 . The implant of    claim 2    wherein: 
 each second wing has said upper portion with a different thickness; and  
 wherein the upper width can be selected by choosing said second wing with said upper portion of the desired thickness.  
 
     
     
         4 . The implant of    claim 1    wherein: 
 said first wing has upper and lower portions;  
 said second wing has upper and lower portions;  
 an upper saddle is defined among the body and the upper portions of the first and second wings;  
 a lower saddle is defined among the body and the lower portions of the first and second wing;  
 wherein the upper width of the upper saddle is defined between the upper portions of the first and second wings;  
 wherein the lower width of the lower saddle is defined between the lower portions of the first and second wings;  
 the implant comprising multiple second wings with each second wing having said upper portion of a different thickness; and  
 wherein the upper width can be selected by choosing said second wing with said portion of the desired thickness.  
 
     
     
         5 . The implant of    claim 1    wherein: 
 at least one of said first wing and said second wing include a recess in order to accommodate the anatomical form of the vertebrae.  
 
     
     
         6 . The implant of    claim 1    wherein: 
 said first wing has upper and lower portions;  
 said second wing has upper and lower portions; and  
 at least one upper portion has a recess in order to accommodate the anatomical form of the vertebrae.  
 
     
     
         7 . The implant of    claim 1    wherein the spinous processes of the spinal column extend from respective vertebral bodies and wherein: 
 at least one of the first and the second wings has an upper portion;  
 said upper portion has a recess in order to accommodate the anatomical form of the spinal column; and  
 wherein said recess is located adjacent to laminae of the vertebrae.  
 
     
     
         8 . The implant of    claim 1    wherein: 
 said groove is wider at the top than the bottom in order to assist the seating of the second wing in the groove.  
 
     
     
         9 . The implant of    claim 1    wherein: 
 said body has an end that is located distally from the first wing; and  
 wherein said end is bulbous.  
 
     
     
         10 . The implant of    claim 1    wherein: 
 said body has an end that is located distally from the first wing; and  
 wherein said end is shaped in a manner that assists in the placement of the body between adjacent spinous processes.  
 
     
     
         11 . The implant of    claim 1    wherein: 
 said body has an end that is located distally from the first wing; and  
 wherein said end is pointed.  
 
     
     
         12 . The implant of    claim 1    wherein: 
 said body has an end that is located distally from the first wing; and  
 wherein said end has first and second sides that are provided at an angle of about 30° to about 60° from a longitudinal axis of the body.  
 
     
     
         13 . The implant of    claim 1    wherein: 
 said device includes a bore in said body which is provided at an acute angle to the body.  
 
     
     
         14 . The implant of    claim 1    wherein: 
 said device includes a bore in said body which is provided at about perpendicular to the body.  
 
     
     
         15 . The implant of    claim 1    wherein: 
 said device includes a first bore in the body;  
 said second wing has tab extending therefrom, which tab includes a second bore there through;  
 wherein with said second wing is received in said groove of said body said first and second bores are aligned; and  
 said device includes a member that is positioned through the first and the second bores in order to secure the second wing to the body.  
 
     
     
         16 . The implant of    claim 10    wherein: 
 said end is removable from said body.  
 
     
     
         17 . An implant for relieving pain associated with the spinal column which is positionable between adjacent spinous processes of the spinal column, comprising: 
 a first unit including a guide and a first wing;    a second wing;    said body including a means for engaging said second wing along a direction from an posterior position along a line toward an anterior position, said body adapted for positioning between the adjacent spinous processes, with the first wing positionable along side the adjacent spinous processes and the second wing positionable along side the spinous processes and opposite to the first wing; and    said engaging means is operable along a direction from an posterior position along a line toward an anterior position.    
     
     
         18 . The implant of    claim 1    which does not limit flexion of the spinal column while limiting extension of the spinal column.  
     
     
         19 . The implant of    claim 17    which does not limit flexion of the spinal column while limiting extension of the spinal column.  
     
     
         20 . The implant of    claim 15    wherein: 
 said body includes a recess that can receive said tab of said second wing.  
 
     
     
         21 . The implant of    claim 1    wherein: 
 said first wing has upper and lower portions;  
 said second wing has upper and lower portions;  
 an upper saddle is defined among the body and the upper portions of the first and second wings;  
 a lower saddle is defined among the body and the lower portions of the first and second wing;  
 wherein the upper width of the upper saddle is defined between the upper portions of the first and second wings;  
 wherein the lower width of the lower saddle is defined between the lower portions of the first and second wings; and  
 wherein at least one of the upper width and the lower width is wider than a spinous process around which the implant is positioned.  
 
     
     
         22 . An implant for relieving pain associated with the spinal column which implant is positionable between adjacent spinous processes of the spinal column, comprising: 
 a distracting unit including a body and a first wing;    a retaining unit including a second wing and a tab extending from said second wing; said distracting unit defining a groove for receiving at least a portion of said second wing and said distraction unit also defining a recess for receiving said tab;    said body including a first bore;    said tab including a second bore;    said first and second bores being alignable with the second wing received in said groove; and    a device that is positionable through the first and second bores in order to secure the retaining unit to the distraction unit.    
     
     
         23 . The implant of    claim 22    wherein: 
 said first bore is threaded; and said device is a screw.  
 
     
     
         24 . The implant of    claim 22   : 
 wherein said first and second bores are alignable along a line extending from a posterior position toward an anterior position relative to the spinal column.    
     
     
         25 . A method of relieving pain due to the development of spinal stenosis and the like in the spinal column including the steps of: 
 accessing adjacent first and second spinous processes of the spinal column;    implanting a distracting unit between the spinous processes, which distracting unit has (1) a body that can maintain a distraction between the first and second spinous processes and (2) a wing which extends from said body along the spinous processes; and    securing a retaining unit to the distracting unit along a line which is from a posterior position to an anterior position.    
     
     
         26 . The method of    claim 25    wherein the securing step includes: 
 positioning the retaining unit in the distracting unit along a line which is from a posterior position to an anterior position.  
 
     
     
         27 . The method of    claim 25    wherein the securing step includes: 
 positioning a screw through the retaining unit and the distracting unit along a line which from a posterior position to an anterior position in order to secure the retaining unit to the distracting unit.  
 
     
     
         28 . The method of    claim 26    wherein the securing step includes: 
 positioning a screw through the retaining unit and the distracting unit along a line which from a posterior position to an anterior position in order to secure the retaining unit to the distracting unit.  
 
     
     
         29 . The method of    claim 25    wherein said first and second wings have first and second planes respectively, and the method includes positioning said second wing relative to the first wing by moving the second wing such that the second plane of the second wing remains substantially parallel to the first plane of the first wing as the second wing is moved into engagement with the distracting unit.  
     
     
         30 . The method of    claim 30    wherein the second wing is secured to the first wing with a fastener which moved along a line that is substantially parallel to the second plane of the second wing in order to secure the retaining unit to the distracting unit.  
     
     
         31 . The method of    claim 25    including the step of: 
 distracting the first and second spinous processes apart prior to inserting the distracting unit between the first and second spinous processes.  
 
     
     
         32 . The method of claim of  25  wherein: 
 said inserting step includes using the distracting unit to distract the first and the second spinous processes as the distracting unit is inserted between the first and the second spinous processes.  
 
     
     
         33 . The implant of    claim 1    wherein: 
 said first wing has upper and lower portions;  
 said second wing has upper and lower portions;  
 an upper saddle is defined among the body and the upper portions of the first and second wings;  
 a lower saddle is defined among the body and the lower portions of the first and second wing;  
 wherein the upper width of the upper saddle is defined between the upper portions of the first and second wings;  
 wherein the lower width of the lower saddle is defined between the lower portions of the first and second wings;  
 there is a height between the upper and the lower saddles; and  
 wherein the upper width is from about 6 mm to about 8 mm, with the lower width being from about 5 mm to about 7 mm and the height is from about 8 mm to about 10 mm.  
 
     
     
         34 . The implant of    claim 1    wherein: 
 said first wing has upper and lower portions;  
 said second wing has upper and lower portions;  
 an upper saddle is defined among the body and the upper portions of the first and second wings;  
 a lower saddle is defined among the body and the lower portions of the first and second wing;  
 wherein the upper width of the upper saddle is defined between the upper portions of the first and second wings;  
 wherein the lower width of the lower saddle is defined between the lower portions of the first and second wings; and  
 there is a height between the upper and the lower saddles; and  
 wherein a trapezoidal shape is defined between the upper width, the lower width and the height.  
 
     
     
         35 . The implant of    claim 1    wherein: 
 said first wing has upper and lower portions;  
 said second wing has upper and lower portions;  
 an upper saddle is defined among the body and the upper portions of the first and second wings;  
 a lower saddle is defined among the body and the lower portions of the first and second wing;  
 wherein the upper width of the upper saddle is defined between the upper portions of the first and second wings;  
 wherein the lower width of the lower saddle is defined between the lower portions of the first and second wings;  
 there is a height between the upper and the lower saddles; and  
 the implant has at least one of the following combinations of dimensions: 
 (a) an upper width of about 6 mm, a lower width of about 5 mm and a height of about 8 mm;  
 (b) an upper width of about 7 mm, a lower width of about 6 mm and a height of about 9 mm; and  
 (c) an upper width of about 8 mm, a lower width of about 7 mm and a height of about 1 mm.  
 
 
     
     
         36 . The implant of    claim 1    wherein: 
 a portion of said body located between the first and second wings defines a trapezoidal shape.  
 
     
     
         37 . An implant for relieving pain associated with the spinal column which implant is positionable between adjacent spinous processes of the spinal column, comprising: 
 a distracting unit including a body and a first wing;    a retaining unit including a second wing which is securable to the body;    the first and second wings having upper portions and lower portions respectively;    the upper portions of the first and second wings and the portion of the body located there between defining an upper saddle;    the lower portions of the first and second wings and the portion of the body located there between defining a lower saddle; and    the portion of the body located between the first and the second saddles defining a trapezoidal shape.    
     
     
         38 . An implant for relieving pain associated with the spinal column which implant is positionable between adjacent spinous processes of the spinal column, comprising: 
 a distracting unit including a body;    a retaining unit which is securable to the body;    said distracting unit and the retaining unit together defining a first saddle and a second saddle, each saddle adapted for receiving a spinous process; and    wherein the first saddle has a first width and the second saddle has a second width and wherein the first width is different from the second width.    
     
     
         39 . The implant of    claim 38    wherein: 
 said first saddle is for receiving an upper spinous process and the second saddle is for receiving a lower spinous process.  
 
     
     
         40 . The implant of    claim 38    wherein: 
 a portion of the body located between the first and the second saddles is substantially trapezoidal shaped.