Mechanically expandable arthroscopic retractors
First Claim
1. A retractor for forming a space at a location in body tissue which is free of naturally occurring space to facilitate arthroscopic surgery, said retractor comprising a body portion having a distal end portion, a proximal end portion, and an intermediate portion disposed between said proximal and distal end portions, and a tubular sleeve at least partially enclosing said body portion, said sleeve having a distal end portion adjacent to said distal end portion of said body portion, said sleeve having a proximal end portion disposed adjacent to said proximal end portion of said body portion, said sleeve having an intermediate portion disposed between said distal and proximal end portions of said sleeve, said distal end portion of said sleeve including a plurality of arms, each of said arms including a distal portion which is connected with the distal end portion of said sleeve and a proximal portion which is connected with the intermediate portion of said sleeve, said distal and proximal portions of said arms being interconnected by connector portions of said arms, said connector portions of said arms having a first edge portion and a second edge portion which is opposite from said first edge portion, said arms being movable from a retracted condition to an extended condition by movement of said sleeve relative to said body portion and deflection of said arms at said connector portions of said arms to form open space which is asymmetrical relative to a central axis of said body portion at the location in the body tissue which is free of naturally occurring space, said connector portion of a first one of said arms being spaced from a connector portion of a second one of said arms by a first distance when said arms are in the extended condition, said second one of said arms being the arm which is next adjacent to the first edge portion of said connector portion of said first one of said arms, said connector portion of said first one of said arms being spaced from a connector portion of a third one of said arms by a second distance which is greater than said first distance when said arms are in the extended condition, said third one of said arms being the arm which is next adjacent to the second edge portion of said connector portion of said first one of said arms, said arms having means for forming the space which is asymmetrical relative to the central axis of said body portion by moving body tissue further away from the central axis of said body portion at a location between said first one of said arms and said second one of said arms than at a location between said first one of said arms and said third one of said arms upon movement of said arms from the retracted condition to the extended condition.
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Accused Products
Abstract
A mechanically expandable retractor for use in arthroscopic surgery. The retractor has an expanding portion at its distal end for expanding against sub-surface tissues when the retractor is in use. The expanding portion includes a plurality of radially expanding The radially outermost surface of each arm when expanded is longitudinally disposed approximately at the distal end of the retractor. The expanding arms can be disposed irregularly circumferentially around the retractor to expand the tissues to provide a working space between adjacent arms. The retractor is inserted through a small percutaneous opening, expanded in sub-surface tissues without significantly damaging the tissue, then collapsed after use for removal. The retractor has a projecting portion at a proximal end of the retractor for manipulating the retractor, to allow the surgeon to push or pull or lever on tissue.
The retractor can be hollow like a cannula to permit the passage of surgical instruments through the retractor, with a side portal into the passage. Alternatively, the retractor can be solid or needle-like. The retractor can include an expandable bladder which can circumscribe the expandable portion of the retractor or be placed elsewhere.
756 Citations
70 Claims
- 1. A retractor for forming a space at a location in body tissue which is free of naturally occurring space to facilitate arthroscopic surgery, said retractor comprising a body portion having a distal end portion, a proximal end portion, and an intermediate portion disposed between said proximal and distal end portions, and a tubular sleeve at least partially enclosing said body portion, said sleeve having a distal end portion adjacent to said distal end portion of said body portion, said sleeve having a proximal end portion disposed adjacent to said proximal end portion of said body portion, said sleeve having an intermediate portion disposed between said distal and proximal end portions of said sleeve, said distal end portion of said sleeve including a plurality of arms, each of said arms including a distal portion which is connected with the distal end portion of said sleeve and a proximal portion which is connected with the intermediate portion of said sleeve, said distal and proximal portions of said arms being interconnected by connector portions of said arms, said connector portions of said arms having a first edge portion and a second edge portion which is opposite from said first edge portion, said arms being movable from a retracted condition to an extended condition by movement of said sleeve relative to said body portion and deflection of said arms at said connector portions of said arms to form open space which is asymmetrical relative to a central axis of said body portion at the location in the body tissue which is free of naturally occurring space, said connector portion of a first one of said arms being spaced from a connector portion of a second one of said arms by a first distance when said arms are in the extended condition, said second one of said arms being the arm which is next adjacent to the first edge portion of said connector portion of said first one of said arms, said connector portion of said first one of said arms being spaced from a connector portion of a third one of said arms by a second distance which is greater than said first distance when said arms are in the extended condition, said third one of said arms being the arm which is next adjacent to the second edge portion of said connector portion of said first one of said arms, said arms having means for forming the space which is asymmetrical relative to the central axis of said body portion by moving body tissue further away from the central axis of said body portion at a location between said first one of said arms and said second one of said arms than at a location between said first one of said arms and said third one of said arms upon movement of said arms from the retracted condition to the extended condition.
- 14. A cannula for forming a space in body tissue to facilitate arthroscopic surgery, said cannula comprising a body portion having a distal end portion, a proximal end portion, and an intermediate portion disposed between said proximal and distal end portions, said body portion including surface means for defining a passage which extends from said proximal end portion to said distal end portion of said body portion and which is adapted to receive an instrument during arthroscopic surgery, said passage in said body portion including surface means for defining a first elongated opening which extends axially along said body portion from the distal end portion of said body portion into the intermediate portion of said body portion and through which the instrument can move to engage body tissue during the performance of arthroscopic surgery, and a tubular sleeve at least partially enclosing said body portion, said sleeve having a distal end portion connected with said distal end portion of said body portion, said sleeve having a proximal end portion disposed adjacent to said proximal end portion of said body portion, said sleeve having an intermediate portion disposed between said distal and proximal end portions of said sleeve, said distal end portion of said sleeve including a first plurality of arms, each of said arms of said first plurality of arms including a distal portion which is connected with a distal end of said sleeve and a proximal portion which is connected with the intermediate portion of said sleeve, said arms of said first plurality of arms being movable from a retracted condition to an extended condition by movement of said sleeve relative to said body portion and deflection of said arms of said first plurality of arms at locations between said distal portions of said arms of said first plurality of arms and said proximal portions of said arms of said first plurality of arms to at least partially form in the body tissue an open space into which the instrument can move from the first elongated opening during the performance of arthroscopic surgery, said intermediate portion of said sleeve including a second plurality of arms which are axially spaced along said sleeve from said first plurality of arms, each of said arms of said second plurality of arms including a distal portion which is connected with said intermediate portion of said sleeve at a location which is axially spaced from locations where said proximal portions of said first plurality of arms are connected with said intermediate portion of said sleeve, each of said arms of said second plurality of arms including a proximal portion which is connected with said proximal portion of said sleeve, said arms of said second plurality of arms being movable from a retracted condition to an extended condition by movement of said sleeve relative to said body portion and deflection of said arms of said second plurality of arms at locations between said distal portions of said arms of said second plurality of arms and said proximal portions of said arms of said second plurality of arms to at least partially form in the body tissue open space into which the instrument can move from the first elongated opening during the performance of arthroscopic surgery, said sleeve having an axially extending portion which is disposed between the proximal portions of the arms of said first plurality of arms and said distal portions of said arms of said second plurality of arms, said axially extending portion of said sleeve being disposed in engagement with said body portion when said arms of said first plurality of arms and said arms of said second plurality of arms are in their extended conditions, said first elongated opening in said body portion facing outward of said body portion in a direction transverse to a longitudinal central axis of said body portion, said first elongated opening in said body portion extending axially along said body portion from a location adjacent to a distal end of said body portion and the distal portions of said arms of said first plurality of arms at least to a location adjacent to ends of the proximal portions of said arms of said second plurality of arms where the proximal portions of said arms of said second plurality of arms are connected with said proximal portion of said sleeve when said arms of said first plurality of arms and said arms of said second plurality of arms are in their extended conditions, said sleeve including surface means for defining a second elongated opening which extends along said sleeve from a location adjacent to the distal end of said body portion and the distal portions of said arms of said first plurality of arms through said axially extending portion of said sleeve disposed between said first plurality of arms and said second plurality of arms to at least a location adjacent to the proximal portions of said arms of said second plurality of arms where the proximal portions of said arms of said second plurality of arms are connected with said proximal portion of said sleeve, said second elongated opening in said sleeve being aligned with said first elongated opening in said body portion and opening outward of said body portion in the direction transverse to the longitudinal central axis of said body portion when said arms of said first plurality of arms and said arms of said second plurality of arms are in their extended conditions to enable the instrument to move from the passage through the first elongated opening and into open space at least partially disposed between said body portion and portions of said first and second pluralities of arms when said first and second pluralities of arms are in their extended conditions.
- 20. A cannula for forming a space at a location in body tissue which is free of naturally occurring space to facilitate arthroscopic surgery, said cannula comprising a body portion having a distal end portion, a proximal end portion, and an intermediate portion disposed between said proximal and distal end portions, said body portion including surface means for defining a passage which extends from said proximal end portion to said distal end portion of said body portion and which is adapted to receive an instrument during arthroscopic surgery, said passage in said body portion including surface means for defining an opening in the distal end portion of said body portion and through which the instrument can move to engage body tissue at the location in the body tissue which is free of naturally occurring space during the performance of arthroscopic surgery, and a tubular sleeve at least partially enclosing said body portion, said sleeve having a distal end portion connected with said distal end portion of said body portion, said sleeve having a proximal end portion disposed adjacent to said proximal end portion of said body portion, said sleeve having an intermediate portion disposed between said distal and proximal end portions of said sleeve, said distal end portion of said sleeve including a plurality of arms, each of said arms including a distal portion which is connected with a distal end of said sleeve and a proximal portion which is connected with the intermediate portion of said sleeve, said distal portions of said arms having a first length, said proximal portions of said arms having a second length which is greater than said first length, said arms being movable from a retracted condition to an extended condition by movement of said sleeve relative to said body portion and deflection of said arms at locations between said distal portions of said arms and said proximal portions of said arms to said form space at the location in the body tissue which is free of naturally occurring space and into which the instrument can move from the passage opening during the performance of arthroscopic surgery, said distal portions of said arms extending transversely to a longitudinal central axis of said sleeve at a first angle when said arms are in the extended condition, said proximal portions of said arms extending relative to the central axis of said sleeve at a second angle which is substantially smaller than said first angle when said arms are in the extended condition, said proximal portions of said arms having means for forming an open space in the body tissue by moving body tissue away from said distal portions of said arms and away from a distal end of said body portion upon movement of said arms from the retracted condition to the extended condition to form an open space in the body tissue adjacent to the distal end of said body portion to facilitate the performance of arthroscopic surgery on the body tissue at the location which is free of naturally occurring space, said passage opening being in communication with the open space formed in the body tissue by movement of body tissue by said outer proximal portions of said arms during movement of said arms from the retracted condition to the extended condition to enable the instrument to move through said passage opening into the open space at the location in the body tissue which is free of naturally occurring space, said distal and proximal portions of said arms being interconnected by connector portions of said arms, said connector portion of a first one of said arms being spaced from said connector portion of a second one of said arms by a first distance when said arms are in the extended condition, said second one of said arms being the arm which is next adjacent to a first edge portion of said first one of said arms, said connector portion of said first one of said arms being spaced from said connector portion of a third one of said arms by a second distance which is greater than said first distance when said arms are in the extended condition, said third one of said arms being the arm which is next adjacent to a second edge portion of said first one of said arms.
- 24. A cannula for forming a space at a location in body tissue which is free of naturally occurring space to facilitate arthroscopic surgery, said cannula comprising a body portion having a distal end portion, a proximal end portion, and an intermediate portion disposed between said proximal and distal end portions, said body portion including surface means for defining a passage which extends from said proximal end portion to said distal end portion of said body portion and which is adapted to receive an instrument during arthroscopic surgery, said passage in said body portion including surface means for defining an opening in the distal end portion of said body portion and through which the instrument can move to engage body tissue at the location in the body tissue which is free of naturally occurring space during the performance of arthroscopic surgery, and a tubular sleeve at least partially enclosing said body portion, said sleeve having a distal end portion connected with said distal end portion of said body portion, said sleeve having a proximal end portion disposed adjacent to said proximal end portion of said body portion, said sleeve having an intermediate portion disposed between said distal and proximal end portions of said sleeve, said distal end portion of said sleeve including a plurality of arms, each of said arms including a distal portion which is connected with a distal end of said sleeve and a proximal portion which is connected with the intermediate portion of said sleeve, said distal portions of said arms having a first length, said proximal portions of said arms having a second length which is greater than said first length, said arms being movable from a retracted condition to an extended condition by movement of said sleeve relative to said body portion and deflection of said arms at locations between said distal portions of said arms and said proximal portions of said arms to form space at the location in the body tissue which is free of naturally occurring space and into which the instrument can move from the passage opening during the performance of arthroscopic surgery, said distal portions of said arms extending generally perpendicular to a longitudinal central axis of said sleeve at a first angle when said arms are in the extended condition, said proximal portions of said arms being skewed relative to the central axis of said sleeve at a second angle which is substantially smaller than said first angle when said arms are in the extended condition, said proximal portions of said arms having means for forming an open space in the body tissue at the location which is free of naturally occurring space by moving body tissue away from said distal portions of said arms and away from a distal end of said body portion upon movement of said arms from the retracted condition to the extended condition to form an open space in the body tissue adjacent to the distal end of said body portion to facilitate the performance of arthroscopic surgery on the body tissue at the location which is free of naturally occurring space, said passage opening being in communication with the open space formed in the body tissue by movement of body tissue by said proximal portions of said arms during movement of said arms from the retracted condition to the expanded condition to enable the instrument to move through said passage opening into the open space at the location in the body tissue which is free of naturally occurring space, said body portion and said sleeve have a cylindrical configuration when said arms are in the retracted condition, said passage opening extends axially along said body portion from a location adjacent to the distal end of said body portion and the distal portions of said arms at least to a location adjacent to the proximal portions of said arms to enable the instrument to move from the passage through the opening, said opening facing radially outward of said body portion, said sleeve including surface means for at least partially defining a slot which extends axially along said sleeve from a location adjacent to the distal end of said body portion and the distal portions of said arms at least to a location adjacent to the proximal portions of said arms, said slot in said sleeve being radially aligned with said opening in said body portion to enable the instrument to move from the passage through the opening in said body portion and into space at least partially disposed between said body portion and said proximal portions of said arms and formed in the body tissue at the location which is free of naturally occurring space by movement of body tissue by said proximal portions of said arms upon movement of said arms from the retracted condition to the extended condition, said distal and proximal portions of said arms being interconnected by connector portions of said arms, said connector portions of said arms having a first edge portion and a second edge portion which is opposite from said first edge portion, said connector portion of a first one of said arms being spaced from a connector portion of a second one of said arms by a first distance when said arms are in the extended condition, said second one of said arms being the arm which is next adjacent to the first edge portion of said connector portion of said first one of said arms, said connector portion of said first one of said arms being spaced from a connector portion of a third one of said arms by a second distance which is greater than said first distance when said arms are in the extended condition, said third one of said arms being the arm which is next adjacent to the second edge portion of said connector portion of said first one of said arms, said opening in said body portion and said slot in said sleeve opening radially outward toward space between proximal portions of said first one of said arms and said third one of said arms when said arms are in the extended condition.
- 29. A cannula for forming a space at a location in body tissue which is free of naturally occurring space to facilitate arthroscopic surgery, said cannula comprising a body portion having a distal end portion, a proximal end portion, and an intermediate portion disposed between said proximal and distal end portions, said body portion including surface means for defining a passage which extends from said proximal end portion to said distal end portion of said body portion and which is adapted to receive an instrument during arthroscopic surgery, said passage in said body portion including surface means for defining an opening in the distal end portion of said body portion and through which the instrument can move to engage body tissue at the location in the body tissue which is free of naturally occurring space during the performance of arthroscopic surgery, and a tubular sleeve at least partially enclosing said body portion, said sleeve having a distal end portion connected with said distal end portion of said body portion, said sleeve having a proximal end portion disposed adjacent to said proximal end portion of said body portion, said sleeve having an intermediate portion disposed between said distal and proximal end portions of said sleeve, said distal end portion of said sleeve including a plurality of arms, each of said arms including a distal portion which is connected with a distal end of said sleeve and a proximal portion which is connected with the intermediate portion of said sleeve, said distal portions of said arms having a first length, said proximal portions of said arms having a second length which is greater than said first length, said arms being movable from a retracted condition to an extended condition by movement of said sleeve relative to said body portion and deflection of said arms at locations between said distal portions of said arms and said proximal portions of said arms to form space at the location in the body tissue which is free of naturally occurring space and into which the instrument can move from the passage opening during the performance of arthroscopic surgery, said distal portions of said arms extending generally perpendicular to a longitudinal central axis of said sleeve at a first angle when said arms are in the extended condition, said proximal portions of said arms being skewed relative to the central axis of said sleeve at a second angle which is substantially smaller than said first angle when said arms are in the extended condition, said proximal portions of said arms having means for forming an open space in the body tissue at the location which is free of naturally occurring space by moving body tissue away from said distal portions of said arms and away from a distal end of said body portion upon movement of said arms from the retracted condition to the extended condition to form an open space in the body tissue adjacent to the distal end of said body portion to facilitate the performance of arthroscopic surgery on the body tissue at the location which is free of naturally occurring space, said passage opening being in communication with the open space formed in the body tissue by movement of body tissue by said proximal portions of said arms during movement of said arms from the retracted condition to the expanded condition to enable the instrument to move through said passage opening into the open space at the location in the body tissue which is free of naturally occurring space, said distal portions of said arms being spaced apart and disposed in a circular array with different spacings between adjacent distal portions of at least some of said arms when said arms are in the extended condition.
- 39. A cannula for forming a space at a location in body tissue which is free of naturally occurring space to facilitate arthroscopic surgery, said cannula comprising a body portion having a distal end portion, a proximal end portion, and an intermediate portion disposed between said proximal and distal end portions, said body portion including surface means for defining a passage which extends from said proximal end portion to said distal end portion of said body portion and which is adapted to receive an instrument during arthroscopic surgery, said passage in said body portion including surface means for defining an opening in the distal end portion of said body portion and through which the instrument can move to engage body tissue at the location in the body tissue which is free of naturally occurring space during the performance of arthroscopic surgery, and a tubular sleeve at least partially enclosing said body portion, said sleeve having a distal end portion connected with said distal end portion of said body portion, said sleeve having a proximal end portion disposed adjacent to said proximal end portion of said body portion, said sleeve having an intermediate portion disposed between said distal and proximal end portions of said sleeve, said distal end portion of said sleeve including a plurality of arms, each of said arms including a distal portion which is connected with a distal end of said sleeve and a proximal portion which is connected with the intermediate portion of said sleeve, said distal portions of said arms having a first length, said proximal portions of said arms having a second length which is greater than said first length, said arms being movable from a retracted condition to an extended condition by movement of said sleeve relative to said body portion and deflection of said arms at locations between said distal portions of said arms and said proximal portions of said arms to form space at the location in the body tissue which is free of naturally occurring space and into which the instrument can move from the passage opening during the performance of arthroscopic surgery, said distal portions of said arms extending generally perpendicular to a longitudinal central axis of said sleeve at a first angle when said arms are in the extended condition, said proximal portions of said arms being skewed relative to the central axis of said sleeve at a second angle which is substantially smaller than said first angle when said arms are in the extended condition, said proximal portions of said arms having means for forming an open space in the body tissue at the location which is free of naturally occurring space by moving body tissue away from said distal portions of said arms and away from a distal end of said body portion upon movement of said arms from the retracted condition to the extended condition to form an open space in the body tissue adjacent to the distal end of said body portion to facilitate the performance of arthroscopic surgery on the body tissue at the location which is free of naturally occurring space, said passage opening being in communication with the open space formed in the body tissue by movement of body tissue by said proximal portions of said arms during movement of said arms from the retracted condition to the expanded condition to enable the instrument to move through said passage opening into the open space at the location in the body tissue which is free of naturally occurring space, said distal and proximal portions of said arms being interconnected by connector portions of said arms, said connector portion of a first one of said arms being spaced from a connector portion of a second one of said arms by a first distance when said arms are in the extended condition, said second one of said arms being the arm which is next adjacent to a first edge portion of said first one of said arms, said connector portion of said first one of said arms being spaced from a connector portion of a third one of said arms by a second distance which is greater than said first distance when said arms are in the extended condition, said third one of said arms being the arm which is next adjacent to a second edge portion of said first one of said arms.
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51. A cannula for forming a space at a location in body tissue which is free of naturally occurring space to facilitate arthroscopic surgery, said cannula comprising a body portion having a distal end portion, a proximal end portion, and an intermediate portion disposed between said proximal and distal end portions, said body portion including surface means for defining a passage which extends from said proximal end portion to said distal end portion of said body portion and which is adapted to receive an instrument during arthroscopic surgery, said passage in said body portion including surface means for defining an opening in the distal end portion of said body portion and through which the instrument can move to engage body tissue at the location in the body tissue which is free of naturally occurring space during the performance of arthroscopic surgery, and a tubular sleeve at least partially enclosing said body portion, said sleeve having a distal end portion connected with said distal end portion of said body portion, said sleeve having a proximal end portion disposed adjacent to said proximal end portion of said body portion, said sleeve having an intermediate portion disposed between said distal and proximal end portions of said sleeve, said distal end portion of said sleeve including a plurality of arms, each of said arms including a distal portion which is connected with a distal end of said sleeve and a proximal portion which is connected with the intermediate portion of said sleeve, said distal portions of said arms having a first length, said proximal portions of said arms having a second length which is greater than said first length, said arms being movable from a retracted condition to an extended condition by movement of said sleeve relative to said body portion and deflection of said arms at locations between said distal portions of said arms and said proximal portions of said arms to form space at the location in the body tissue which is free of naturally occurring space and into which the instrument can move from the passage opening during the performance of arthroscopic surgery, said distal portions of said arms extending generally perpendicular to a longitudinal central axis of said sleeve at a first angle when said arms are in the extended condition, said proximal portions of said arms being skewed relative to the central axis of said sleeve at a second angle which is substantially smaller than said first angle when said arms are in the extended condition, said proximal portions of said arms having means for forming an open space in the body tissue at the location which is free of naturally occurring space by moving body tissue away from said distal portions of said arms and away from a distal end of said body portion upon movement of said arms from the retracted condition to the extended condition to form an open space in the body tissue adjacent to the distal end of said body portion to facilitate the performance of arthroscopic surgery on the body tissue at the location which is free of naturally occurring space, said passage opening being in communication with the open space formed in the body tissue by movement of body tissue by said proximal portions of said arms during movement of said arms from the retracted condition to the expanded condition to enable the instrument to move through said passage opening into the open space at the location in the body tissue which is free of naturally occurring space, said sleeve includes a second plurality of arms disposed between said intermediate portion of said sleeve and said proximal end portion of said sleeve, said second plurality of arms being deflectable from a retracted condition to an extended condition by movement of said sleeve relative to said body portion to form space which extends between said second plurality of arms and the distal end portion of said sleeve at the location in the body tissue which is free of naturally occurring space, surface means for defining a side opening in said intermediate portion of said sleeve between said plurality of arms in said distal end portion of said sleeve and said second plurality of arms, said opening in the distal end portion of said body portion connecting said side opening in said sleeve with said passage in said body portion.
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52. A cannula as set forth in claim 517 wherein said arms of said second plurality of arms are spaced apart and disposed in a circular array with different spacings between adjacent portions of at least some of said arms of said second plurality of arms when said arms of said second plurality of arms are in the extended condition.
- 53. A cannula for forming a space at a location in body tissue which is free of naturally occurring space to facilitate arthroscopic surgery, said cannula comprising a longitudinally extending body portion having a distal end portion, a proximal end portion, and an intermediate portion disposed between said proximal and distal end portions, said body portion including surface means for defining a passage which extends from said proximal end portion to said distal end portion of said body portion and which is adapted to receive an instrument during arthroscopic surgery, and a tubular sleeve at least partially enclosing said body portion, said sleeve having a distal end portion connected with said distal end portion of said body portion, said sleeve having a proximal end portion disposed adjacent to said proximal end portion of said body portion, said sleeve having an intermediate portion disposed between said distal and proximal end portions of said sleeve, said distal end portion of said sleeve including a plurality of arms, each of said arms including a distal portion which is connected with a distal end of said sleeve and a proximal portion which is connected with the intermediate portion of said sleeve, said arms being movable from a retracted condition to an extended condition by movement of said sleeve relative to said body portion and deflection of said arms at locations between said distal portions of said arms and said proximal portions of said arms to form space at the location in the body tissue which is free of naturally occurring space, said arms having means for forming an open space in the body tissue at the location which is free of naturally occurring space by moving body tissue away from said body portion upon movement of said arms from the retracted condition to the extended condition to form an open space in the body tissue to facilitate the performance of arthroscopic surgery on the body tissue at the location which is free of naturally occurring space, said surface means for defining a passage in said body portion including surface means for defining an elongated opening in said body portion and which faces outward of said body portion in a direction transverse to a longitudinal central axis of said body portion and which extends axially along said body portion from a location adjacent to a distal end of said body portion and the distal portions of said arms at least to a location adjacent to ends of the proximal portions of said arms where the proximal portions of said arms are connected with said intermediate portion of said sleeve when said arms are in the extended condition to enable the instrument to move from the passage through the elongated opening in said body portion, said sleeve including surface means for defining an elongated opening which extends axially along said sleeve from a location adjacent to the distal end of said body portion and the distal portions of said arms at least to a location adjacent to the proximal portions of said arms where the proximal portions of said arms are connected with said intermediate portion of said sleeve, said elongated opening in said sleeve being aligned with said elongated opening in said body portion and opens outward of said body portion in the direction transverse to the longitudinal central axis of said body portion when said arms are in the extended condition to enable the instrument to move from the passage through the elongated opening in said body portion and into open space at least partially disposed between said body portion and said proximal portions of said arms and formed in the body tissue at the location which is free of naturally occurring space by movement of body tissue by said arms upon movement of said arms from the retracted condition to the extended condition to enable the instrument to move through the passage and through the elongated opening in said body portion into the open space at the location in the body tissue which is free of naturally occurring space, said distal portions of said arms being spaced apart and disposed in a circular array with different spacings between adjacent distal portions of at least some of said arms when said arms are in the expanded condition.
Specification