Devices and methods for percutaneous tissue retraction and surgery

Abstract

Methods and devices for performing percutaneous surgery in a patient are provided. A retractor includes a working channel formed by a first portion coupled to a second portion. The first and second portions are movable relative to one another from an unexpanded configuration to an expanded configuration to increase the size of the working channel along the length of the working channel while minimizing trauma to skin and tissue.

What is claimed is: 
     
       1. A retractor for percutaneous surgery in a patient, comprising:
 a first portion having a proximal end and a distal end; 
 a second portion having a proximal end coupled to said proximal end of said first portion, said second portion having a distal end and including opposite edges overlapping adjacent edges of said first portion at least adjacent said distal ends to form a working channel, said working channel having a length between said distal ends and said proximal ends of said first and second portions and a size between said first portion and said second portion along said length, wherein:
 said first and second portions are positionable in an unexpanded configuration with said distal ends of said first and second portions in the patient and said proximal ends of said first and second portions outside the patient; and 
 
 said first and second portions are movable to an expanded configuration wherein said working channel tapers in size from said distal ends in the patient to said proximal ends outside the patient and said opposite edges of said second portion overlap adjacent edges at said distal end of said first portion in said expanded configuration. 
 
     
     
       2. The retractor of  claim 1 , further comprising an endoscopic viewing instrument extending through said working channel. 
     
     
       3. The retractor of  claim 1 , further comprising a microscopic viewing instrument over said working channel. 
     
     
       4. The retractor of  claim 1 , wherein one of said first and second portions includes a bracket extending from said proximal end thereof that is engageable to a flexible arm. 
     
     
       5. The retractor of  claim 1 , wherein said first portion and said second portion extend completely about said working channel from said proximal ends of said first and second portions to said distal ends of said first and second portions. 
     
     
       6. The retractor of  claim 1 , further comprising a ratchet and pawl mechanism at said proximal ends of said first and second portions to maintain said first and second portions in said expanded configuration. 
     
     
       7. The retractor of  claim 1 , further comprising:
 a pair of coupling members engaging said first portion to said second portion; 
 a lever arm extending from respective ones of each of said pair of coupling members; and 
 said coupling members each have a first position wherein said first portion is pivotal relative to said second portion and are moveable to a second position wherein said coupling members fix said first portion relative to said second portion, said lever arms being moveable to move said coupling members from said second position to said first position. 
 
     
     
       8. The retractor of  claim 1 , wherein said first portion is pivotally coupled to said second portion about a pivot axis located proximally of said proximal ends of said first and second portions. 
     
     
       9. The retractor of  claim 1 , wherein said second portion includes a partial cylindrical body and said first portion includes a partial cylindrical body positioned about said partial cylindrical body of said second portion. 
     
     
       10. The retractor of  claim 1 , wherein said working channel has a figure eight shape along said length in said expanded configuration. 
     
     
       11. The retractor of  claim 10 , wherein in said unexpanded configuration said working channel has a generally circular cross-section along said length and in said expanded configuration said working channel has a dimension in said second portion transverse to a primary expansion direction of said first and second portions that is less than a dimension of said working channel in said first portion transverse to said primary expansion direction. 
     
     
       12. The retractor of  claim 1 , wherein said second portion includes a semi-cylindrical body and said first portion includes a semi-cylindrical body positioned about said semi-cylindrical body of said second portion. 
     
     
       13. The retractor of  claim 12 , wherein said body of said first portion is flexible. 
     
     
       14. The retractor of  claim 12 , wherein said body of said first portion includes opposite edges extending therealong between said proximal end and said distal end of said first portion. 
     
     
       15. The retractor of  claim 14 , wherein said body of said first portion has a perimeter length between said opposite edges, said perimeter length being greater at said distal end of said first portion than at said proximal end of said first portion. 
     
     
       16. The retractor of  claim 14 , wherein said body of said second portion includes opposite edges extending therealong between said proximal end and said distal end, said body of said second portion further including an engagement surface extending along at least a portion of each of said opposite edges thereof. 
     
     
       17. The retractor of  claim 16 , wherein said opposite edges of said first portion engage adjacent ones of said engagement surfaces of said second portion when in said expanded configuration. 
     
     
       18. The retractor of  claim 1 , wherein said first portion includes a collar at said proximal end thereof and said second portion includes a collar at said proximal end thereof. 
     
     
       19. The retractor of  claim 18 , wherein said first portion and said second portion are pivotally coupled to one another at said collars. 
     
     
       20. The retractor of  claim 19 , wherein:
 said collar of said first portion includes first and second extensions extending therefrom on opposite sides of said first portion; and 
 said collar of said second portion includes first and second recesses therein on opposite sides of said second portion, said first and second extensions positionable in respective ones of said first and second recesses. 
 
     
     
       21. The retractor of  claim 20 , wherein said collar of said second portion includes first and second extensions extending along said first and second recesses of said second collar, said first and second extensions of said first portion are each pivotally coupled to an adjacent one of said first and second extensions of said second portion in respective ones of said first and second recesses of said second portion. 
     
     
       22. The retractor of  claim 21 , wherein said collar of said first portion includes first and second recesses therein adjacent respective ones of said first and second extensions of said first portion, said first and second extensions of said second portion are positionable in respective ones of said first and second recesses of said first portion. 
     
     
       23. The retractor of  claim 22 , wherein:
 said first and second extensions of said first portion each contact an engagement surface in each of said first and second recesses of said second portion in said expanded configuration; and 
 said first and second extensions of said second portion each contact an engagement surface in each of said first and second recesses of said first portion in said expanded configuration. 
 
     
     
       24. A retractor for percutaneous surgery in a patient, comprising:
 a first portion having opposite edges extending between a proximal end and a distal end; 
 a second portion coupled to said first portion and having opposite edges extending between a proximal end and a distal end, said second portion including an engagement surface extending along at least a portion of each of said opposite edges thereof, said first and second portions forming a working channel having a length extending between said distal ends and said proximal ends of said first and second portions; 
 said first and second portions having an unexpanded configuration wherein said edges of said first portion extends around said second portion; and 
 said first and second portions being pivotal relative to one another about said proximal ends to an expanded configuration wherein said opposite edges of said first portion engage adjacent ones of said engagement surfaces of said second portion. 
 
     
     
       25. The retractor of  claim 24 , wherein:
 said first and second portions are positionable in the patient in said unexpanded configuration with said distal ends of said first and second portions in the patient and said proximal ends of said first and second portions outside the patient; and 
 said expanded configuration increases a size of said working channel between said first portion and said second portion along said entire length of said working channel. 
 
     
     
       26. The retractor of  claim 24 , wherein in said unexpanded configuration said working channel has a generally circular cross-section along said length and in said expanded configuration said working channel has a dimension in said second portion transverse to a pivot direction of said first and second portions that is less than a dimension of said working channel in said first portion transverse to said pivot direction. 
     
     
       27. The retractor of  claim 24 , wherein said first portion is pivotally coupled to said second portion about a pivot axis located proximally of said proximal ends of said first and second portions. 
     
     
       28. The retractor of  claim 24 , wherein said second portion includes a semi-cylindrical body and said first portion includes a semi-cylindrical body positioned about said semi-cylindrical body of said second portion. 
     
     
       29. The retractor of  claim 28 , wherein said body of said first portion is flexible. 
     
     
       30. The retractor of  claim 28 , wherein said body of said first portion has a perimeter length between said opposite edges, said perimeter length being greater at said distal end of said first portion than at said proximal end of said first portion. 
     
     
       31. The retractor of  claim 28 , wherein said body of said first portion has a thickness that is less than a thickness of said body of said second portion. 
     
     
       32. The retractor of  claim 24 , wherein said first portion includes a collar at said proximal end thereof and said second portion includes a collar at said proximal end thereof. 
     
     
       33. The retractor of  claim 32 , wherein:
 said collar of said first portion includes first and second extensions extending therefrom on opposite sides of said first portion; and 
 said collar of said second portion includes first and second recesses therein on opposite sides of said second portion, said collar of said second portion including first and second extensions along each of said first and second recesses, said first and second extensions of said first portion are positioned in respective ones of said first and second recesses of said second portion and pivotally engaged to first and second extensions of said second portion. 
 
     
     
       34. The retractor of  claim 33 , wherein said collar of said first portion includes first and second recesses along said first and second extensions thereof, said first and second extensions of said second portion are each positioned in respective ones of said first and second recesses of said first portion. 
     
     
       35. The retractor of  claim 34 , wherein:
 said first and second extensions of said first portion each contact an engagement surface in each of said first and second recesses of said second portion in said expanded configuration; and 
 said first and second extensions of said second portion each contact an engagement surface in each of said first and second recesses of said first portion in said expanded configuration. 
 
     
     
       36. A retractor for percutaneous surgery in a patient, comprising:
 a first portion extending between a proximal end and a distal end, said first portion including a collar extending about said proximal end; and 
 a second portion extending between a proximal end and a distal end, said second portion including a collar extending about said proximal end, said first and second portions forming a working channel having a length extending between said distal ends and said proximal ends of said first and second portions and a size between said first and second portions, wherein said collar of said first portion is pivotally coupled to said collar of said second portion and said first and second portions are pivotal relative to one another between an unexpanded configuration and an expanded configuration and in at least said unexpanded configuration said first portion overlaps said second portion between said proximal and distal ends to enclose said working channel along said first and second portions. 
 
     
     
       37. The retractor of  claim 36 , wherein:
 said first and second portions are positionable in said unexpanded configuration with said distal ends of said first and second portions in the patient and said proximal ends of said first and second portions outside the patient; and 
 said expanded configuration increases said size of said working channel between said first portion and said second portion from said proximal ends of said first and second portions to said distal ends of said first and second portions. 
 
     
     
       38. The retractor of  claim 36 , further comprising a viewing element selected from the group comprising: an endoscopic viewing instrument and a microscopic viewing instrument. 
     
     
       39. The retractor of  claim 36 , wherein said first portion includes opposite edges extending therealong between said proximal end and said distal end. 
     
     
       40. The retractor of  claim 36 , wherein said second portion includes a partial cylindrical body and said first portion includes a partial cylindrical body positioned about said partial cylindrical body of said second portion. 
     
     
       41. The retractor of  claim 36 , wherein said second portion includes a semi-cylindrical body and said first portion includes a semi-cylindrical body positioned about said semi-cylindrical body of said second portion. 
     
     
       42. The retractor of  claim 41 , wherein said body of said first portion is flexible. 
     
     
       43. The retractor of  claim 41 , wherein:
 said body of said first portion has a perimeter length between opposite edges thereof that is greater at said distal end of said first portion than at said proximal end of said second portion; and 
 said body of said second portion has a perimeter length between opposite edges thereof that is generally the same at said distal end and said proximal end of said second portion. 
 
     
     
       44. The retractor of  claim 36 , wherein said collar of first portion is pivotally coupled to said collar of said second portion about a pivot axis located proximally of said proximal ends of said first and second portions. 
     
     
       45. The retractor of  claim 44 , wherein:
 said collar of said first portion includes first and second extensions extending therefrom on opposite sides of said first portion; and 
 said collar of said second portion includes first and second recesses therein on opposite sides of said second portion, said collar of said second portion including first and second extensions along each of said first and second recesses, said first and second extensions of said first portion are positioned in respective ones of said first and second recesses of said second portion and pivotally engaged to first and second extensions of said second portion. 
 
     
     
       46. The retractor of  claim 45 , wherein said collar of said first portion includes first and second recesses along said first and second extensions thereof, said first and second extensions of said second portion are each positioned in respective ones of said first and second recesses of said first portion. 
     
     
       47. The retractor of  claim 46 , wherein:
 said first and second extensions of said first portion each contact an engagement surface in each of said first and second recesses of said second portion in said expanded configuration; and 
 said first and second extensions of said second portion each contact an engagement surface in each of said first and second recesses of said first portion in said expanded configuration. 
 
     
     
       48. A retractor for percutaneous surgery in a patient, comprising:
 a first portion extending between a proximal end and a distal end, said first portion including a collar extending about said proximal end; and 
 a second portion extending between a proximal end and a distal end, said second portion including a collar extending about said proximal end, said first and second portions forming a working channel having a length extending between said distal ends and said proximal ends of said first and second portions and a size between said first and second portions, wherein said collar of said first portion is pivotally coupled to said collar of said second portion and said first and second portions are pivotal relative to one another between an unexpanded configuration and an expanded configuration, wherein in said unexpanded configuration said working channel includes a generally circular cross-section along said length and in said expanded configuration said working channel has a dimension in said second portion transverse to a pivot direction of said first and second portions that is less than a dimension in said first portion transverse to said pivot direction. 
 
     
     
       49. A retractor for percutaneous surgery in a patient, comprising:
 a first portion extending between a proximal end and a distal end, said first portion including a collar extending about said proximal end; and 
 
       a second portion extending between a proximal end and a distal end, said second portion including a collar extending about said proximal end, said first and second portions forming a working channel having a length extending between said distal ends and said proximal ends of said first and second portions and a size between said first and second portions, wherein said collar of said first portion is pivotally coupled to said collar of said second portion and said first and second portions are pivotal relative to one another between an unexpanded configuration and an expanded configuration, wherein said first portion includes opposite edges extending therealong between said proximal end and said distal end and said first portion has a perimeter length between said opposite edges, said perimeter length being greater at said distal end of said first portion than at said proximal end of said second portion. 
     
     
       50. A retractor for percutaneous surgery in a patient, comprising:
 a first portion extending between a proximal end and a distal end, said first portion including a collar extending about said proximal end; and 
 a second portion extending between a proximal end and a distal end, said second portion including a collar extending about said proximal end, said first and second portions forming a working channel having a length extending between said distal ends and said proximal ends of said first and second portions and a size between said first and second portions, wherein said collar of said first portion is pivotally coupled to said collar of said second portion and said first and second portions are pivotal relative to one another between an unexpanded configuration and an expanded configuration, wherein said first portion includes opposite edges extending therealong between said proximal end and said distal end and said second portion includes opposite edges extending therealong between said proximal end and said distal end, said second portion further including an engagement surface extending along at least a portion of each of said opposite edges thereof, said second portion being positioned between said opposite edges of said first portion when said first and second portions are in said expanded configuration. 
 
     
     
       51. The retractor of  claim 50 , wherein said opposite edges of said first portion engage adjacent ones of said engagement surfaces of said second portion when said first and second portions are in said expanded configuration. 
     
     
       52. A method for performing a surgical procedure at a location in a patient, comprising:
 making an incision in the skin and tissue of the patient to access the location; 
 forming a working channel through the incision to the location by sequentially dilating tissue and inserting a distal end of a retractor into the patient with a proximal end of the retractor located outside of the patient; and 
 pivoting a first portion of the retractor relative to a second portion of the retractor about a pivot axis adjacent the proximal end of the retractor such that edges of the second portion overlap edges of the first portion to expand the working channel through the incision. 
 
     
     
       53. The method of  claim 52 , further comprising:
 mounting an expansion instrument on the proximal end of the retractor before pivoting the first portion relative to the second portion. 
 
     
     
       54. The method of  claim 52 , further comprising:
 positioning a viewing element to view the location through the retractor. 
 
     
     
       55. The method of  claim 52 , wherein forming the working channel includes sequentially dilating skin and tissue through the incision before inserting the distal end of the retractor. 
     
     
       56. The method of  claim 52 , wherein the pivot axis is located proximally of the proximal end of the retractor. 
     
     
       57. The method of  claim 56 , wherein the retractor defines a working channel therethrough that is substantially enclosed by the retractor. 
     
     
       58. The method of  claim 56 , wherein the retractor is expanded by pivoting a first portion of the retractor relative to a second portion of the retractor about a pivot axis adjacent the proximal end of the retractor. 
     
     
       59. The method of  claim 56 , wherein the location is adjacent the spinal column of the patient. 
     
     
       60. A surgical method for accessing a location in a patient, comprising:
 sequentially dilating tissue of the patient to the location; 
 placing an unexpanded retractor through the sequentially dilated tissue; 
 expanding the retractor predominantly in a first direction through the tissue by pivoting a first portion of the retractor relative to a second portion of the retractor about a pivot axis such that edges of the second portion overlap edges of the first portion; and 
 performing a surgical procedure through the expanded retractor. 
 
     
     
       61. A surgical method for accessing a location in a patient, comprising:
 placing an unexpanded retractor through sequentially dilated tissue to the location; 
 expanding the retractor to an expanded configuration by pivoting a first portion of the retractor relative to a second portion of the retractor about a pivot axis such that edges of the second portion overlap edges of the first portion; 
 unexpanding the retractor before removing the retractor; and 
 removing the retractor from the patient. 
 
     
     
       62. The method of  claim 61 , further comprising locking the retractor in the expanded configuration. 
     
     
       63. The method of  claim 62 , further comprising unlocking the retractor before unexpanding the retractor. 
     
     
       64. The method of  claim 61 , wherein the retractor is expanded by pivoting a first portion of the retractor relative to a second portion of the retractor about a pivot axis adjacent a proximal end of the retractor. 
     
     
       65. The method of  claim 64 , wherein the pivot axis is located proximally of the proximal end of the retractor. 
     
     
       66. A tissue retractor for surgery in a patient, comprising:
 a first portion and a second portion coupled to said first portion, said first and second portions each having a length extending along a longitudinal axis between a distal end and a proximal end thereof such that said proximal ends are positionable outside the patient and said distal ends are positionable in the patient, said first portion being pivotable relative to said second portion about a pivot axis that extends transverse to said longitudinal axes; 
 a working channel extending therealong between said distal ends and said proximal ends of said first and second portions; and 
 said first and second portions have an unexpanded configuration wherein said working channel has a generally circular cross-section and an expanded configuration wherein said working channel has a non-circular cross-section tapering from said distal end to said proximal end, wherein said first portion substantially envelopes said second portion in said unexpanded configuration. 
 
     
     
       67. The retractor of  claim 66 , wherein said first and second portions are locked in said expanded configuration. 
     
     
       68. The retractor of  claim 66 , wherein said first portion has a flexible body. 
     
     
       69. The retractor of  claim 66 , wherein said first portion is pivotally coupled to said second portion at said proximal ends thereof. 
     
     
       70. The retractor of  claim 66 , wherein said first portion is pivotally coupled to said second portion along a pivot axis is located proximally of said proximal ends of said first portion and said second portion. 
     
     
       71. A tissue retractor for surgery in a patient, comprising:
 a first portion and a second portion coupled to said first portion, said first and second portions each having a length extending along a longitudinal axis between a distal end and a proximal end thereof such that said proximal ends are positionable outside the patient and said distal ends are positionable in the patient, said first portion being pivotable relative to said second portion about a pivot axis that extends transverse to said longitudinal axes; 
 a working channel extending therealong between said distal ends and said proximal ends of said first and second portions; and 
 said first and second portions have an unexpanded configuration wherein said working channel has a generally circular cross-section and an expanded configuration wherein said working channel has a non-circular cross-section tapering from said distal end to said proximal end, wherein said second portion includes a partial cylindrical body and said first portion includes a partial cylindrical body positioned about said partial cylindrical body of said second portion.