Method and apparatus for treating intervertebral disks

Abstract

The method and apparatus as shown in FIGS. 8-10 in which a fluid expandable member ( 208 ) is positioned in concentric relation about a needle ( 202 ). The fluid expandable member ( 208 ) is expanded into the nucleus pulposus potential space bordered by the annulus fibrosus of an intervertebral disk. Then, thermoplastic material in a flowing state is injected by a needle ( 202 ) within the annulus fibrosus to collapse the fluid expandable member ( 208 ) and occupy the space formerly occupied by the fluid expandable member ( 208 ).

1. A method for treating an intervertebral disk of the spine, comprising:
 selecting an intervertebral disk of the spine;   providing an injection device having an expandable member about an injection needle for a thermoplastic material;   injecting said expandable member and said needle into the annulus fibrosus of said selected disk;   expanding said expandable member into the annulus fibrosus of said selected disk; and   then injecting a thermoplastic material from said needle into said annulus fibrosus of said selected disk to occupy the space defined by said expandable member.   
     
     
       2. The A method defined in  claim 1 , further for treating an intervertebral disk of the spine, comprising:
 selecting an intervertebral disk of the spine; 
 obtaining an injection device having an expandable member about an injection needle for injecting a thermoplastic material; 
 heating the thermoplastic material to a flowable state; 
 inserting said expandable member and said needle into the annulus fibrosus of said intervertebral disk; 
 expanding said expandable member into the annulus fibrosus of said intervertebral disk to occupy a space; and 
 injecting a thermoplastic material from said needle into said annulus fibrosus of said selected disk to occupy the space defined by said expandable member; 
 injectingwherein said thermoplastic material is injected from said needle under a pressure greater than the pressure for expanding said expandable member to effect collapsing of said expandable member with said thermoplastic material occupying the space formerly occupied by said expandable member. 
 
     
     
       3. The method defined in for treating an intervertebral disk of the spine of claim  1  2, further comprising:
 removing nucleus pulposus from said annulus fibrosus prior to insertion of said expandable member and said needle into said annulus fibrosus. 
 
     
     
       4. An injection device fortreating an intervertebral disk of the spine of a patient, comprising:
 a hollow needle for the injection of a thermoplastic material into the annulus fibrosus of a disk from the projecting end of the needle;   an expandable member about said hollow needle for expanding into the annulus fibrosus of the disk prior to injection of the thermoplastic material in the annulus fibrosus; and   a heater for heating said thermoplastic material to effect flowing thereof prior to injection into the annulus fibrosus.   
     
     
       5. An injection system for treating an intervertebral disk of a spines comprising:
 an injection device including a hollow needle for injecting a thermoplastic material within the annulus fibrosus of a disk, and an expandable member about said hollow needle to form an annulus between said needle and said expandable member;   a fluid pressure device to provide pressurized fluid in said annulus for expanding said expandable member into said annulus fibrosus;   a heating device for heating the thermoplastic material; and   a force applying device for forcing said thermoplastic material from said needle in a flowing state.   
     
     
       6. The An injection system as defined in  claim 5  for treating an intervertebral disk of a spine, further comprising:
 an injection device including a hollow needle having a purgeable volume of at least 5 cubic centimeters for injecting a thermoplastic material within the annulus fibrosus of a disk, and an expandable member about said hollow needle to form an annulus between said needle and said expandable member; 
 a heating device for heating the thermoplastic material; 
 a force applying device for forcing said thermoplastic material from said needle in a flowing state; and 
 a concentric sleeve about said needle for forming said an annulus between said sleeve and said needle, said expandable member mounted about said sleeve. 
 
     
     
       7. The injection system as defined in of  claim 6 , wherein said sleeve has a plurality of openings therein for communicating fluid to said expandable member for expanding said expandable member within said annulus fibrosus. 
     
     
       8. The injection system as defined in of claim  5  wherein said fluid pressure device includes a pressurized liquid, and a hydraulically actuated piston for pressurizing said liquid 6, further comprising:
 a fluid pressure device to provide pressurized fluid in said annulus for expanding said expandable member into said annulus fibrosus. 
 
     
     
       9. An injection gun for injecting a thermoplastic material between a joint of a patient, comprising:
 a chamber for receiving said thermoplastic material in a non-flowing state;   a heater adjacent said chamber for heating said thermoplastic material to a flowing state;   a hollow injection needle operatively connected to said heater to receive the flowing thermoplastic material from said heater for injection between the joint of the patient; and   a hydraulic force applying assembly to apply hydraulic force against said thermoplastic material to force the thermoplastic material when heated to a flowing state from said needle.   
     
     
       10. The injection gun as defined in device of claim  9  30, further comprising:
 a plug of said thermoplastic material within said chamber, said hydraulic force applying assembly including a hydraulically actuated piston adjacent said plug for forcing said thermoplastic material from said needle after said thermoplastic material is heated to a flowing state. 
 
     
     
       11. The injection gun as defined in device of claim  10  28, further comprising:
 a fluid pressure source for said hydraulically actuated piston; and 
 a foot operated pedal associated with said fluid pressure source to provide a selected fluid pressure to said piston and heated thermoplastic material. 
 
     
     
       12. The injection gun as defined in device of claim  9  31, further comprising:
 an expandable member about said hollow needle to form an annulus between said needle and said expandable member; and 
 a fluid pressure device to provide pressurized fluid in said annulus for expanding said expandable member a distraction element for insertion into the annulus fibrosus to create a void. 
 
     
     
       13. The injection gun as defined in device of  claim 12 , further comprising:
 a substantially rigid concentric sleeve about said hollow needle for forming an annulus between said sleeve and said needle; 
 an expandable member mounted about said sleeve; and 
 a fluid pressurization device to provide pressurization fluid in said annulus for expanding said expandable member, said expandable member being in fluid communication with said annulus wherein said distraction element comprises an expandable member about said hollow needle to form an annulus between said needle and said expandable member. 
 
     
     
       14. The injection gun as defined in device of claim  9  30, wherein said thermoplastic material comprises gutta percha. 
     
     
       15. The injection gun as defined in device of claim  9  30, wherein said thermoplastic material comprises a gutta percha compound in which gutta percha is between 15% and 40% by weight of the compound. 
     
     
       16. The injection gun as defined in device of claim  9  30, wherein said heater heating element heats said thermoplastic material compound for flowing at a temperature between about 150 C and 200 C. 
     
     
       17. The injection gun as defined in  claim 9 , further comprising:
 a generally cylindrical housing forming the chamber to receive a plug of thermoplastic material and having opposed open ends, said cylindrical housing being removable from said injection needle; and   a threaded end plug for each of said open ends when said housing is removed from said injection needle for sealing of said thermoplastic material therein.   
     
     
       18. The injection device as defined in of claim  17  31, wherein said heater heating element is removably mounted adjacent one of said open ends upon removal of an associated end plug. 
     
     
       19. The method for treating an intervertebral disk of the spine of claim 3, wherein injecting a thermoplastic material from said needle into said annulus fibrosus of said selected disk to occupy a space comprises injecting a thermoplastic material from said needle into said annulus fibrosus of said selected disk to occupy a space defined by the removal of said nucleus pulposus. 
     
     
       20. The injection system of claim 8, wherein said fluid pressure device includes a pressurized liquid and a hydraulically actuated piston for pressurizing said liquid. 
     
     
       21. The injection device of claim 30, wherein said injection device comprises an injection gun. 
     
     
       22. The injection device of claim 30, wherein said heating element comprises a heater. 
     
     
       23. The injection device of claim 30, wherein said heating element is situated adjacent said chamber. 
     
     
       24. The injection device of claim 30, wherein said hollow injection needle is operatively connected to said heating element to receive said thermoplastic material from said heating element. 
     
     
       25. The injection device of claim 30, wherein said force applying assembly comprises a hydraulic force applying assembly. 
     
     
       26. The injection device of claim 30, wherein said force applying assembly comprises a mechanical force applying assembly. 
     
     
       27. The injection device of claim 26, wherein said mechanical force applying assembly comprises a hand operated trigger. 
     
     
       28. The injection device of claim 10, wherein said force applying assembly comprises a hydraulic force applying assembly for hydraulically actuating said piston. 
     
     
       29. The injection device of claim 13, further comprising:
 a fluid pressure device to provide pressurized fluid in said annulus for expanding said expandable member.   
     
     
       30. An injection device for injecting a thermoplastic material into a joint of a patient, comprising:
 a chamber for receiving said thermoplastic material in a non-flowing state;   a heating element for heating said thermoplastic material to a flowing state;   a hollow injection needle having a purgeable volume of at least 5 cubic centimeters to receive the flowing thermoplastic material for injection into said joint; and   a force applying assembly to apply force against said thermoplastic material to force the thermoplastic material from said needle when heated to a flowing state; and   a distraction element for insertion into the annulus fibrosus to create a void, wherein the distraction element comprises:
 a substantially rigid concentric sleeve about said hollow needle for forming an annulus between said sleeve and said needle; 
 an expandable member mounted about said sleeve; and 
 a fluid pressurization device to provide pressurization fluid in said annulus for expanding said expandable member, said expandable member being in fluid communication with said annulus. 
   
     
     
       31. An injection device for injecting a thermoplastic material into a joint of a patient, comprising:
 a chamber for receiving said thermoplastic material in a non-flowing state;   a heating element for heating said thermoplastic material to a flowing state;   a hollow injection needle having a purgeable volume of at least 5 cubic centimeters to receive the flowing thermoplastic material for injection into said joint; and   a force applying assembly to apply force against said thermoplastic material to force the thermoplastic material from said needle when heated to a flowing state; and   wherein said chamber for receiving said thermoplastic material comprises:
 a generally cylindrical housing forming the chamber to receive a plug of thermoplastic material and having opposed open ends, said cylindrical housing being removable from said injection needle; and 
 a threaded end plug for each of said open ends when said housing is removed from said injection needle for sealing of said thermoplastic material therein.