Detachable dilator blade

Abstract

A tissue retraction system includes a dilator and a first retractor member and a retraction assembly. The dilator is configured to be inserted into a tissue body and also includes at least one engagement member. The first retractor member includes a body and at least one engagement member that is configured to attach to the at least one engagement member of the dilator so as to removably attach the retractor member to the dilator body. The retraction assembly includes a retractor body and at least a second retractor member that is movably supported by the retractor body. The retractor body is configured to be attached to the first retractor member. The tissue protection system may also include a neuromonitoring member configured to determine a characteristics of the tissue.

What is claimed: 
     
       1. A tissue retraction system configured to dilate a tissue body, the tissue retraction system comprising:
 a dilator configured to be inserted into the tissue body toward a surgical site, the dilator including a dilator body that is elongate along a respective longitudinal direction and sized to dilate the tissue body, the dilator body defining a proximal end and a distal end that is spaced from the proximal end along the respective longitudinal direction, and the dilator body terminates at first and second dilator sides that extend between the proximal and distal ends, the dilator further including at least one engagement member that is recessed along at least one of the dilator sides; 
 a first retractor member that includes a body that is elongate along the respective longitudinal direction and at least one engagement member that is configured to attach to the at least one engagement member of the dilator so as to removably attach the first retractor member to the dilator body along the respective longitudinal direction, the first retractor member and the dilator cooperate so as to define a passageway when the first retractor member is attached to the dilator body, wherein one of the at least one engagement members of the dilator and the first retractor member defines a protrusion that is elongate along the respective longitudinal direction and the other of the at least one engagement members of the dilator and the first retractor member defines a groove that is elongate along the respective longitudinal direction and receives the protrusion so as to removably attach the first retractor member to the dilator; and 
 a retractor assembly including a retractor body and at least a second retractor member that is movably supported by the retractor body, the retractor body configured to be attached to the first retractor member, wherein the retractor body is configured so as to cause the second retractor member to splay away from the first retractor member when the first retractor member is attached to the retractor body. 
 
     
     
       2. The tissue retraction system as recited in  claim 1 , wherein the engagement members of the dilator and the first retractor member attach such that the first retractor member is movable with respect to the dilator along the respective longitudinal direction. 
     
     
       3. The tissue retraction system as recited in  claim 1 , wherein the passageway is enclosed along all directions that are substantially perpendicular to the longitudinal direction. 
     
     
       4. The tissue retraction system as recited in  claim 1 , wherein the body of the first retractor member defines a proximal end and a distal end that is spaced from the proximal end along the longitudinal direction, the body of the first retractor member terminates at first and second retractor sides that extend between the proximal and distal ends of the body of the first retractor member, and the at least one engagement member of the first retractor member extends out of least one of the retractor sides. 
     
     
       5. The tissue retraction system as recited in  claim 1 , wherein the dilator defines first and second protrusions, and the first retractor member defines first and second grooves that are configured to receive the first and second protrusions. 
     
     
       6. The tissue retraction system as recited in  claim 1 , wherein the first retractor member includes an engagement assembly that is configured to secure the body of the first retractor member to the retractor assembly. 
     
     
       7. The tissue retraction system as recited in  claim 6 , wherein the retractor assembly defines an engagement opening that is configured to receive the engagement assembly to secure the first retractor member to the retractor assembly. 
     
     
       8. The tissue retraction system as recited in  claim 7 , wherein the retractor assembly includes a retention member that is configured to retain the engagement assembly in the engagement opening so as to secure the first retractor member to the retractor assembly. 
     
     
       9. The tissue retraction system as recited in  claim 8 , wherein the retractor assembly includes a biasing member that is configured to bias the retention member in a direction away from the retractor body. 
     
     
       10. The tissue refraction system as recited in  claim 1 , further comprising a fastener that is configured to connect the first retractor member to the retractor assembly. 
     
     
       11. The tissue retraction system as recited in  claim 10 , wherein the first retractor member defines a hole, and the retractor assembly defines an engagement opening that is configured to be aligned with the hole such that the engagement opening and the hole are configured to collectively receive the fastener to secure the first retractor member to the retractor assembly. 
     
     
       12. The tissue retraction system as recited in  claim 1 , further comprising
 a neuromonitoring member configured to detect at least one property of the tissue body, the neuromonitoring member configured to be coupled to the dilator. 
 
     
     
       13. The tissue retraction system as recited in  claim 12 , wherein the dilator body defines an outer dilator surface, and the neuromonitoring member is configured to be coupled along the outer dilator surface. 
     
     
       14. The tissue retraction system as recited in  claim 12 , wherein the neuromonitoring member includes at least one electrode that is configured to detect at least one property of the tissue body. 
     
     
       15. The tissue retraction system as recited in  claim 14 , wherein the neuromonitoring member includes at least one electrical connection member that is configured to transmit electrical energy to the electrode from an electrical power source. 
     
     
       16. A tissue retraction system configured to dilate a tissue body, the tissue retraction system comprising:
 a dilator configured to be inserted into the tissue body toward a surgical site, the dilator including a dilator body that is elongate along a respective longitudinal direction and sized to dilate the tissue body, the dilator further including at least one engagement member; 
 a first retractor member that includes a body that is elongate along the respective longitudinal direction, at least one engagement member that is configured to attach to the at least one engagement member of the dilator so as to removably attach the first retractor member to the dilator body, wherein the first retractor member and the dilator cooperate so as to define a passageway when the first retractor member is attached to the dilator body, the first retractor member including an engagement assembly; and 
 a retractor assembly including a retractor body, an engagement opening that is configured to receive the engagement assembly, a retention member that is configured to retain the engagement assembly in the engagement opening so as to secure the first retractor member to the retractor assembly, and a biasing member that is configured to bias the retention member in a direction away from the retractor body, the retractor assembly further including at least a second retractor member that is movably supported by the retractor body such that the second retractor member is moveable away the first retractor member when the first retractor member is secured to retractor assembly. 
 
     
     
       17. The tissue retraction system as recited in  claim 16 , wherein the engagement members of the dilator and the first retractor member attach such that the first retractor member is movable with respect to the dilator along the respective longitudinal direction. 
     
     
       18. The tissue retraction system as recited in  claim 16 , wherein the passageway is enclosed along all directions that are substantially perpendicular to the longitudinal direction. 
     
     
       19. The tissue retraction system as recited in  claim 16 , wherein one of the at least one engagement members of the dilator and the first retractor member defines a protrusion that is elongate along the respective longitudinal direction, and the other of the at least one engagement members of the dilator and the first retractor member defines a groove that is elongate along the respective the longitudinal direction and receives the protrusion so as to removably attach the first retractor member to the dilator. 
     
     
       20. The tissue retraction system as recited in  claim 16 , wherein the dilator body defines a proximal end and a distal end that is spaced from the proximal end along the longitudinal direction, the dilator body terminates at first and second dilator sides that extend between the proximal and distal ends, and the at least one engagement member of the dilator is recessed in at least one of the dilator sides. 
     
     
       21. A tissue retraction system, comprising:
 a dilator having a dilator body that defines a proximal end, a distal end that is spaced from the proximal end along a respective longitudinal direction, an inner surface, and an outer surface, the dilator including an electrode, the dilator body terminating at first and second dilator sides that extend between the proximal and distal ends, the dilator including at least one engagement member that is recessed along at least one of the dilator sides;   a retractor member having a body that defines a proximal end, a distal end, at least one engagement member that is configured to attach to the at least one engagement member of the dilator so as to removably attach the retractor member to the dilator body along the respective longitudinal direction, and a retractor member opening that extends through the body from the proximal end to the distal end, the retractor member opening being configured to receive the dilator therethrough, wherein one of the at least one engagement members of the dilator and the retractor member defines a protrusion that is elongate along the respective longitudinal direction and the other of the at least one engagement member of the dilator and the retractor member defines a groove that is elongate along the respective longitudinal direction and receives the protrusion so as to removably attach the retractor member to the dilator; and   a mechanomyogram (MMG) neuromonitoring system, the electrode of the dilator being electrically coupled to an electrically conductive member extending longitudinally along the dilator, the electrically conductive member being connected to the MMG neuromonitoring system.   
     
     
       22. The system of claim 21, wherein the retractor member defines a circumferentially-enclosed working channel that extends from the proximal end to the distal end of the body. 
     
     
       23. The system of claim 21, wherein the electrode is configured to detect properties or characteristics of tissue in which the first dilator is disposed. 
     
     
       24. The system of claim 21, wherein the electrode is configured to provide output to a user interface so as to provide guidance information to a user that can be used to guide the first dilator without impinging upon nerve tissue. 
     
     
       25. The system of claim 21, wherein the electrode is configured to monitor the direction, pathology, and proximity of nerves. 
     
     
       26. The system of claim 21, wherein the electrode is configured to continue to detect the properties or characteristics of tissue after the dilator is placed in a desired position. 
     
     
       27. The system of claim 21, wherein the dilator is longer than the retractor member. 
     
     
       28. The system of claim 21, wherein the retractor member is tubular. 
     
     
       29. The system of claim 21, wherein the dilator includes a curved outer surface that mates with a curved inner surface of the retractor member. 
     
     
       30. The system of claim 21, wherein an inner diameter of the retractor member is greater than an outer diameter of the dilator. 
     
     
       31. The system of claim 21, wherein the dilator is longitudinally movable relative to the retractor member. 
     
     
       32. The system of claim 21, wherein the dilator and the retractor member are movable relative to one another to dilate tissue.