Patent Description:
Access tubes and/or retractors can be used to provide a physician with an access portal or "working channel" to a surgical treatment site within patient anatomy. Various minimally invasive procedures, including spinal procedures such as decompression, fusion, external fixation, and the like, may be performed through such access portals. The access tubes used in these procedures must often be secured in position relative to the treatment site via external devices, such as operating table-mounted devices and/or anatomical-mounted devices, such as bone anchors, including pedicle anchors and the like, by way of non-limiting examples. Once the access tube is positioned relative to the patient anatomy so as to provide the working channel open to the target treatment site, retractor members (also referred to as "retractor blades" or simply "blades"), can be inserted through the working channel and manipulated to engage soft tissue at the treatment site and pull the soft tissue toward the wall of the access tube. Additional retractor members can be inserted through the working channel as needed to pull additional soft tissue at the treatment site toward the wall of the access tube. In this manner, soft tissue can be retracted from the treatment site, providing the physician with increased access to and visualization of the treatment site, including visualization of the exiting nerve. However, during a surgical procedure, some of the soft tissue can tend to move or "creep" into the distal opening of the access tube, which can impede visualization of the treatment site, including visualization of the exiting nerve.

According to a first aspect of the present invention, there is provided a retractor member, as defined in claim <NUM>. Optional further features of the retractor member are defined in the dependent claims. The retractor member is configured for insertion through a channel of an access member and for moving soft tissue at a treatment site accessible through the channel. The retractor member includes a body having a proximal end and a distal end spaced from each other along a longitudinal direction. The distal end defines a retractor blade and the body defines a first surface and a second surface opposite each other along a transverse direction substantially perpendicular to the longitudinal direction. The retractor includes an attachment device configured to selectively attach the body to a portion of the access member such that the body is extendable through the working channel and is translatable relative to the access member along the longitudinal direction while the body is attached to the portion of the access member.

The body has a first side and a second side spaced from each other along a lateral direction substantially perpendicular to the longitudinal and transverse directions, and the attachment device extends from at least one of the first and second sides at a longitudinal portion of the body located intermediate the proximal and distal ends, such that the attachment device is configured to reside within the working channel for securing the retractor member to an inner surface of the access member.

The attachment device comprises a pair of wings each extending circumferentially from the first and second sides, respectively, at the longitudinal location, wherein the pair of wings are compliant and are configured to be flexed inward toward each other from a neutral configuration to a flexed configuration by the inner surface of the access member when the pair of wings are disposed in the channel, such that a return force of the pair of wings causes the pair of wings to engage the inner surface of the access member so as to attach the body to the portion of the access member.

At the longitudinal portion and in a plane orthogonal to the longitudinal direction, the second surface of the body may define a first radius and the outer surfaces of the wings may define another radius that is greater than the first radius when the pair of wings are in the neutral configuration.

The body may define a proximal body portion that extends from the pair of wings to the proximal end and a distal body portion that may extend from the pair of wings to the distal end along the longitudinal direction, and the distal and proximal body portions may be at least partially circumferentially offset from each other.

The distal and proximal body portions may be entirely circumferentially offset from each other.

The attachment device may comprise an attachment member separate from the body, wherein the attachment member comprises:
a slide formation configured to slidably engage a complimentary slide formation of the body so as to allow the attachment member to translate along the body and within the channel; and
a locking member extending circumferentially away from the slide formation, wherein the locking member may be compliant and configured to be flexed inward toward a central axis of the access member when the locking member is disposed in the channel, such that a return force of the locking member causes the locking member to engage the inner surface of the access member so as to attach the body to the portion of the access member.

The complimentary slide formation of the body may comprise a guide slot, the locking member may comprise a circumferential wall configured to slide annularly between the outer surface of the body and an inner surface of the access member, wherein the slide formation of the attachment member may comprise a slider configured to reside within the guide slot, wherein the slider may extend inwardly from the circumferential wall along the transverse direction.

The attachment device may comprise an attachment member separate from the body, at least a portion of the attachment member may comprise magnetic material, and the body may comprise one or more magnets each configured for selective attachment to the magnetic material of the at least a portion of the attachment member.

The body may define an internal chamber and may further define a proximal port and a plurality of vacuum ports each in fluid communication with the internal chamber, wherein the plurality of vacuum ports may be defined in the second surface, and the proximal port is connectable to a vacuum source; and
the attachment device may comprise a plurality of ring seals each disposed in one of the plurality of vacuum ports, wherein the plurality of ring seals may be configured to sealingly engage an inner wall surface of the access member when a vacuum pressure is supplied within the internal chamber.

The attachment device may comprise a wire configured to transition from an insertion configuration to a deployed configuration, wherein the wire may be configured to be contained in an elongated insertion device when in the insertion configuration, and the wire may be further configured to spring outwardly so as to extend at least partially circumferentially around an inner wall surface of the access member so as to force the body toward the inner wall surface when in the deployed configuration.

The body may have a first side and a second side spaced from each other along a lateral direction substantially perpendicular to the longitudinal and transverse directions, the first surface may be arcuate and concave between the first and second sides in a plane orthogonal to the longitudinal direction, and the second surface may be arcuate and convex between the first and second sides in the plane.

At least at one of the proximal and distal ends, the body may define an end portion that is flared, such that the end portion defines a maximum lateral dimension that is greater than a maximum lateral dimension of an adjacent portion of the body that extends from the end portion toward the opposite one of the proximal and distal ends.

At least at one of the proximal and distal ends, the body may define an end portion that is angularly offset from an adjacent portion of the body that extends from the end portion toward the opposite one of the proximal and distal ends.

The end portion may be angularly offset from the adjacent portion of the body.

At least a proximal portion of the body may be plastically deformable so as to be bent away from a central axis of the access member after the body is attached to the portion of the access member.

The body may include at least one electrically conductive sensor at the distal end, and the at least one electrically conductive sensor may be in electrical communication with an electric lead that is spaced from the at least one electrically conductive sensor and may be configured for communicating sensor information obtained by the at least one sensor to a control unit.

The body may be formed of an electrically conductive material, and the retractor member may further comprise electrical insulation covering a major portion of the body, wherein the body may include a distal exposed portion at the distal end, the distal exposed portion may define the at least one electrically conductive sensor, the body may further include a proximal exposed portion at the proximal end, and the proximal exposed portion may define the electric lead.

The body may be formed of an electrically insulative material, and the at least one electrically conductive sensor may be embedded in the body at the distal end.

A system for retracting soft tissue is disclosed, the system includes an access member having a proximal end and a wall that extends from the proximal end to a distal end of the access member. The wall extends about a central axis in a plane orthogonal to the central axis such that an inner surface of the wall defines a channel that extends along an axial direction oriented along the central axis. The system includes a retractor body having a proximal end and a distal end that is configured to engage soft tissue and is spaced from the proximal end of the retractor body along a longitudinal direction. The retractor body defines a first surface and a second surface opposite each other along a transverse direction substantially perpendicular to the longitudinal direction. The system includes an attachment device that is coupled to the retractor body and includes a proximal mount and a distal mount configured to respectively mount to the proximal and distal ends of the access member. At least one of the proximal and distal mounts is configured to move between an unlocked configuration, in which the proximal and distal mounts are longitudinally spaced from each other by a first distance, and a locked configuration, in which the proximal and distal mounts are longitudinally spaced from each other by a second distance less than the first distance. The second distance corresponds to a distance between the proximal and distal ends of the access member along the axial direction.

The proximal and distal mounts may each comprise a hook configured to hook the respective proximal and distal ends of the access member.

The retractor body may be longitudinally translatable relative to the proximal and distal mounts at least when the attachment device is in the locked configuration.

The system may further comprise an actuator configured to actuate the at least one of the proximal and distal mounts from the unlocked configuration to the locked configuration.

The actuator may comprise at least one elongate member that extends from the distal mount, through a receptacle of the proximal mount, and to a control member spaced from the proximal mount in a proximal direction oriented along the longitudinal direction, wherein the control member may be configured to be manipulated to actuate the at least one of the proximal and distal mounts from the unlocked configuration to the locked configuration.

The retractor body may define a slot extending along the longitudinal direction, and each of the proximal and distal mounts may include a slide member that extends within the slot and may be configured to slide longitudinally along the slot so as to guide longitudinal movement of the respective mount relative to the retractor body.

The retractor body may further define a series of ratchet grooves arranged longitudinally along the slot, and the proximal mount may include a flexible member having a tooth configured to engage the series of ratchet grooves, wherein the flexible member may be configured to iterate between <NUM>) a neutral configuration in which the tooth resides within one of the ratchet grooves so as to retain a relative longitudinal position between the proximal mount and the retractor member, and <NUM>) a disengaged configuration in which the tooth is remote from each of the series of ratchet grooves.

The proximal mount may include a handle portion.

The system may further comprise an instrument releasably coupled to the attachment device, the instrument may comprise:.

The coupling mechanism may be further configured to move the actuator so as to actuate the at least one of the proximal and distal mounts from the unlocked configuration to the locked configuration.

The proximal mount may comprise a mount base and an engagement member, wherein the actuator may extend between the mount base and the engagement member and may be configured to actuate longitudinal movement of the engagement member relative to the mount base between the unlocked configuration and the locked configuration.

The actuator may comprise a bias mechanism having at least one spring that biases the engagement member away from the mount base in a bias direction along the longitudinal direction so as to actuate the engagement member to the locked configuration;.

The retractor body may comprise an aperture and the coupling mechanism may comprise a pin configured to <NUM>) reside within the aperture so as to couple with the retractor member when the coupling mechanism is in the coupled configuration, and <NUM>) move remote from the aperture so as to de-couple from the retractor member when the coupling mechanism is in the de-coupled configured.

The coupling mechanism may include a button that is connected to the pin and may be configured to iterate between a first position, in which the pin resides within the aperture, and a second position, in which the pin is remote from the aperture.

The actuator may be a tensile member configured to selectively apply tension between the proximal and distal mounts so as to actuate the at least one of the proximal and distal mounts.

According to an additional example, a system for retracting soft tissue includes an access member having a proximal end and a wall that extends from the proximal end to a distal end of the access member. The wall extends about a central axis in a plane orthogonal to the central axis such that an inner surface of the wall defines a channel that extends along an axial direction oriented along the central axis. The system includes a retractor body having a proximal end and a distal end that is configured to engage soft tissue and is spaced from the proximal end of the retractor body along a longitudinal direction. The retractor body defines a first surface and a second surface opposite each other along a transverse direction substantially perpendicular to the longitudinal direction. At least one of the access member and the retractor body defines one or more openings, while the other of the access member and the retractor body includes one or more protrusions that are complimentary with the one or more openings and are configured for insertion within the one or more openings so as to couple the retractor body to the access member.

Each of the one or more protrusions may define a stem and a head extending outwardly from the stem, the head being wider than the stem.

The one or more openings may comprise an array of openings extending outwardly into the wall from the inner surface thereof, the array may define a plurality of columns, each of the columns comprising a longitudinally aligned subset of the plurality of openings, wherein the columns may be circumferentially spaced from one another along the wall,
the one or more protrusions may comprise a plurality of protrusions each extending from the second surface of the retractor member along the transverse direction and aligned with each other along the longitudinal direction, wherein the plurality of protrusions may be configured to reside selectively within at least one of the columns such that the heads overlap at least a portion of the wall along the axial direction.

The retractor body may have a proximal portion and a distal portion that are configured to be angularly offset from each other in a plane extending along the longitudinal and transverse directions, and at least one of the one or more openings may extend through the proximal portion from the first surface to the second surface, and
the one or more protrusions may comprise a plurality of protrusions extending along the longitudinal direction from a proximal surface of the access member, wherein the proximal surface may be located at the proximal end of the access member, and the plurality of protrusions may be circumferentially spaced from each other along the proximal surface.

The foregoing summary, as well as the following detailed description of illustrative embodiments of the present application, will be better understood when read in conjunction with the appended drawings. For the purposes of illustrating the structures of the present application, there is shown in the drawings illustrative embodiments. It should be understood, however, that the application is not limited to the precise arrangements and instrumentalities shown. In the drawings:.

The present disclosure can be understood more readily by reference to the following detailed description taken in connection with the accompanying figures and examples, which form a part of this disclosure. It is to be understood that this disclosure is not limited to the specific devices, methods, applications, conditions or parameters described and/or shown herein, and that the terminology used herein is for the purpose of describing particular embodiments by way of example only and is not intended to be limiting of the scope of the present disclosure. Also, as used in the specification including the appended claims, the singular forms "a," "an," and "the" include the plural, and reference to a particular numerical value includes at least that particular value, unless the context clearly dictates otherwise.

The term "plurality", as used herein, means more than one. When a range of values is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent "about," it will be understood that the particular value forms another embodiment. All ranges are inclusive and combinable.

The terms "approximately" and "substantially", as used herein with respect to dimensions, angles, and other geometries, takes into account manufacturing tolerances. Further, the terms "approximately" and "substantially" can include <NUM>% greater than or less than the stated dimension or angle. Further, the terms "approximately" and "substantially" can equally apply to the specific value stated.

The embodiments described below pertain to retractor members (also referred to herein as "retractors") for use in a surgical access system that includes an access member, such as an access tube. In particular, the embodiments described below pertain to retractors configured for insertion through a working channel of the access member to engage and retract soft tissue at a surgical treatment site distally located from the working channel. More particularly, the embodiments described below include various attachment devices allowing selective attachment of the retractor to a circumferential location of the access tube, thereby securing the soft tissue in a retracted position. As used herein with reference to an access member, the term "circumferential" generally refers to a direction revolving around a central axis of the access member, and specifically refers to any direction having a directional component that is offset from both (<NUM>) a radial direction perpendicular to the central axis and (<NUM>) an axial direction along which the central axis extends. Thus, the term "circumferential," as used herein with reference to an access member, refers to a direction along any of a line, an arc, a circle, an ellipse, a polygon, or an irregular shape, that revolves at least partially around the central axis of the access member.

Some of the attachment devices described below are located entirely on the retractor, while others are employed in complimentary components or features of the retractor and the access member, while yet others are employed is a separate component of the surgical access system. Additionally, a majority of the attachment devices described below allow the retractor to move in the following ways relative to the access member, while yet remaining secured to an inner wall surface thereof: translation along an axial direction oriented along a central axis of the member; and rotation (i.e., revolution) about the central axis circumferentially along the inner wall surface. These movements allow the physician to adjust the retractor position within the working channel as needed to account for variations in patient anatomy (e.g., variations between the anatomies of different patients). Such retractors and complimentary attachment devices that are moveable in any of the foregoing ways can also be repositioned during a surgical procedure to adjust the retraction of soft tissue as needed, while yet remaining attached to the inner wall surface so that when the physician has repositioned the retractor to satisfaction, the attachment device will hold the position of the retractor relative to the access member after the physician releases the retractor.

In additional embodiments described below, the retractor is employed as part of a surgical access system that includes an instrument coupled to a proximal end of the retractor and configured for manipulating the retractor to engage soft tissue. The instruments described below are configured to selectively couple with and de-couple from the retractor as needed. In further embodiments, the insertion instrument is also configured to actuate the attachment device from an un-attached configuration, in which the attachment device is un-attached to the access member, to an attached configuration, in which the attachment device attaches the retractor to the access member, as described above.

Referring now to <FIG>, an exemplary embodiment of a surgical access system <NUM> for a spinal procedure includes an access member <NUM> for providing access to a surgical treatment site within the patient and a retractor member <NUM> configured to extend through the access member <NUM> and engage soft tissue at the treatment site. The access member <NUM> has a body <NUM>, which can be tubular, and is configured to extend distally from an ex vivo location with respect to patient anatomy to an in vivo target location within the patient anatomy. By way of a non-limiting example, the access member <NUM> can be configured to extend through the skin line <NUM> and to the target location, which is at or adjacent an intended surgical treatment site. The access member <NUM> includes a shield or wall <NUM> that defines an internal port or channel <NUM>, also referred to herein as a "working channel" <NUM>, that is elongate along a central axis <NUM> of the access member <NUM> and is open from the ex vivo location to the target location along an axial direction X (i.e., the direction oriented along the central axis <NUM>). The access member <NUM> extends from a proximal end <NUM> to a distal end <NUM> along the axial direction X. In the illustrated example, the central axis <NUM> defines a spinal approach axis, which is oriented along a transforaminal approach, such as through the Kambin's triangle. In this example, the target location of the access member <NUM> is at the facet line <NUM> of adjacent vertebral bodies <NUM>, and the treatment site includes the intervertebral disc space <NUM>. It should be appreciated, however, that other approaches are within the scope of the present disclosure, including but not limited to interlaminar, lateral, and anterior approaches. With the access member <NUM> positioned at the proper depth and orientation so as to extend to the treatment site, the central axis <NUM> intersects the treatment site. In this manner, instrumentation can be advanced distally through the access member <NUM> toward the treatment site as needed. To prepare the treatment site for certain instruments, one or more retractor members <NUM> can be inserted through the working channel <NUM>, such as along the central axis <NUM>, and can be manipulated to engage and retract soft tissue (including soft tissue near the exiting nerve), such as by pulling or otherwise moving the soft tissue along a radial direction R away from and substantially perpendicular to the central axis <NUM> (and thus also substantially perpendicular to the axial direction X). If a portion of the engaged soft tissue extends within the working channel, the retraction moves such soft tissue toward the wall <NUM> of the access member <NUM>. The retraction of soft tissue can be employed, among other things, to expose and provide visualization of the exiting nerve so that the physician can avoid damaging or contacting the exiting nerve during the spinal procedure.

The surgical access system <NUM> can be employed as a sub-system of a primary surgery system <NUM>, such as a spinal surgery system. With respect to the spinal surgical procedure depicted, the spinal surgery system <NUM> can include, among other things, a connector <NUM> having one or more arms <NUM> for connecting the access member <NUM> to an anchor, such as a pedicle anchor, such as a contra-lateral pedicle anchor <NUM>, as shown. In this manner, the position of the access member <NUM> and its working channel <NUM> can be affixed relative to the patient anatomy, such as via the anchor <NUM> and the connector <NUM>. The spinal surgery system <NUM> can be configured as more fully described in <CIT>, entitled "MULTI-SHIELD SPINAL ACCESS SYSTEM" ("the '<NUM> Reference"); and <CIT>, entitled "CONTROL MEMBER FOR ADJUSTING ACCESS TUBE POSITION, AND RELATED SYSTEMS AND METHODS" ("the '<NUM> Reference").

Referring now to <FIG>, the wall <NUM> of the access member <NUM> defines an outer wall surface <NUM> and an inner wall surface <NUM> spaced from each other along the radial direction R. As shown, the outer wall surface <NUM> can have an oblong profile in a plane orthogonal to the central axis <NUM>. Additionally, the wall <NUM> can also define a secondary channel <NUM> along the axial direction X. For example, the inner wall surface <NUM> can define one or more projections <NUM> that extend generally radially inward toward the central axis <NUM> so as to define a partition between the working channel <NUM> and the secondary channel <NUM>. In the illustrated embodiment, the secondary channel <NUM> can receive one or more optical instruments, such as a camera or other type of image sensor, by way of non-limiting examples. In such embodiments, the partition between the working channel <NUM> and the secondary channel <NUM> is helpful for preventing mechanical interference between the optical instrument(s) and any instruments extending through the working channel <NUM>. The secondary channel <NUM> is preferably open to the working channel <NUM> at least along a direction having a directional component along the radial direction R. As shown, the wall <NUM> can extend an entire revolution about the central axis <NUM>, thereby providing the access member <NUM> with its tubular configuration. It should be appreciated, however, that the wall <NUM> can extend less than a full revolution about the central axis <NUM>, while continuing to provide a working channel <NUM> and optionally also a secondary channel <NUM>.

As shown in <FIG>, the retractor member <NUM> (also referred to herein as a "retractor" <NUM>) has a retractor body <NUM> that extends from a proximal end <NUM> to a distal end <NUM> spaced from each other along a longitudinal direction L. It should be appreciated that the retractor body <NUM> can define the entire retractor <NUM> in monolithic fashion, or can define a portion of the retractor <NUM>, such as a major portion thereof in combination with one or more separate yet connected (or connectable) portions of the retractor <NUM>, by way of non-limiting examples. The distal end <NUM> can have a blade-like geometry, and can thus be referred to as a "retractor blade" or simply a "blade". The retractor <NUM> has a length along the longitudinal direction L greater than a length of the access member <NUM> along the axial direction X. In this manner, the retractor <NUM> can be inserted through the working channel <NUM> to the treatment site and can be manipulated by its proximal end <NUM> so as to control placement of the distal end <NUM> to engage soft tissue as needed at or near the treatment site. It should be appreciated that the proximal end <NUM> can also have a blade-like geometry and can thus also be referred to as a "retractor blade" or "blade". Such opposed-blade configurations can be advantageous because they need not require a specific end to be inserted through the access member <NUM>.

With the soft tissue engaged, the retractor <NUM> can be moved to the inner wall surface <NUM> and attached thereto by an attachment device, described in more detail below. As shown in <FIG>, the retractor body <NUM> has a first or "inner" surface <NUM> and a second or "outer" surface <NUM> spaced from each other along a transverse direction T substantially perpendicular to the longitudinal direction L. The outer surface <NUM> of the retractor body <NUM> is preferably arcuate and convex in a plane orthogonal to the longitudinal direction L. Additionally, the outer surface <NUM> preferably defines a radius R1 substantially equivalent to a radius R2 of the inner wall surface <NUM>. In this manner, the retractor body <NUM> can be moved flush against the inner wall surface <NUM> for connection thereto, so as to avoid obstructing the working channel <NUM>. It should be appreciated that when the retractor body <NUM> is flush against the inner wall surface <NUM>, the transverse direction T is substantially oriented along the radial direction R of the access member <NUM>. The inner surface <NUM> of the retractor body <NUM> is preferably arcuate and concave in the orthogonal plane, and preferably extends in parallel or concentric fashion with the convex outer surface <NUM> in the orthogonal plane.

The retractor <NUM> is formed of a material that is biocompatible (i.e., a "biomaterial") and is sufficiently rigid so that manipulation at the proximal end <NUM> causes retraction of soft tissue at the distal end <NUM> (or vice versa if the opposite end is inserted through the working channel <NUM>). The material also preferably provides the retractor body <NUM> with deformability, such as via plastic deformation, allowing a first portion 3a of the retractor body <NUM> to be bent relative to a second portion 3b of the retractor body, as shown in <FIG>. In this manner, when retractor body <NUM> has achieved satisfactory retraction of soft tissue (and the retractor body <NUM> has been secured to the access member <NUM> by an attachment device, as described in more detail below), the physician can bend the first portion 3a away from the central axis <NUM> and out of the way, thereby reducing the profile of the retractor body <NUM> in a proximal direction P, for example. Such retractor body materials can be metal (e.g., stainless steel, such as a <NUM> series and/or a <NUM> series stainless steel), polymeric (e.g., polyphenylsulfone (PPSU)), and/or a composite material (e.g., carbon fiber), by way of non-limiting examples.

Referring now to <FIG>, different variants of the retractor body <NUM> are shown, each of which includes an integrated attachment device <NUM> for coupling the retractor body <NUM> to the wall <NUM> of the access member <NUM>. For example, the attachment device <NUM> is configured to attach the retractor body <NUM> to a circumferential portion of the inner wall surface <NUM> as selected by the physician. In particular, the attachment device <NUM> shown in each of these variants comprises at least one compliant member <NUM> configured to flex from a neutral configuration when disposed outside the working channel <NUM> to a flexed configuration when inserted within the working channel <NUM>. The compliant member <NUM> can also be referred to as a "locking spring" or "locking ring". When in the flexed configuration, the compliant member <NUM> imparts a return force (which can also be referred to as a "locking force") against the inner wall surface <NUM> sufficient to push the retractor body <NUM> toward the inner wall surface <NUM>, effectively securing the retractor body <NUM> in place relative to the wall <NUM>. It should be appreciated that the compliant member <NUM> is configured such that the locking force is sufficient to maintain retraction of soft tissue engaged by the distal end <NUM> of the retractor body <NUM>, yet not so great so as to prevent the physician from further subsequently manipulating the retractor body <NUM> to adjust engagement with soft tissue, such as to translate the retractor body <NUM> along the axial direction X, rotate the retractor body <NUM> about the central axis <NUM>, or any combination of the foregoing motions. Furthermore, the compliant member <NUM> of the present embodiments is configured to effectively automatically secure the retractor body <NUM> in place within the working channel <NUM> once the physician has finished manipulating the proximal end <NUM> thereof (so long as the compliant member <NUM> resides within the working channel <NUM>).

Each of the retractor bodies <NUM> defines a first side <NUM> and a second side <NUM> spaced from each other along a lateral direction A substantially perpendicular to the longitudinal and transverse directions L, T. The compliant member <NUM> of the attachment device <NUM> can include a pair of compliant members <NUM> or "wings" that extend circumferentially outward from the first and second sides <NUM>, <NUM> at a longitudinal portion 3c of the retractor body <NUM> that is intermediate the proximal and distal ends <NUM>, <NUM> thereof. Thus, longitudinal portion 3c can also be referred to an "intermediate" portion 3c of the retractor body <NUM>. The retractor body <NUM> also defines a proximal body portion 3d that extends from the intermediate portion 3c to the proximal end <NUM> along the proximal direction P, and a distal body portion 3e that extends from the intermediate body portion 3c to the distal end <NUM> along a distal direction D. It should be appreciated that the proximal and distal directions P, D are each monodirectional components of the longitudinal direction L, which is bi-directional. A radially outer surface of the wings <NUM> defines a radius R3 that is slightly larger than the radius R2 of the inner wall surface <NUM> when in the neutral configuration. In this manner, inserting the wings <NUM> within the working channel <NUM> causes the wings <NUM> to flex inwardly toward the central axis <NUM> (and also toward one another), thereby providing the locking force. One or both of the wings <NUM> can define a helical end surface <NUM> that is contiguous with the respective first or second side <NUM>, <NUM> of the retractor body <NUM>. In the illustrated embodiments, the helical end surface <NUM> defines a proximal surface of each wing <NUM>, although the distal surface of one or both of the wings <NUM> can also extend helically to the respective first or second side <NUM>, <NUM> in similar fashion.

As shown in <FIG>, the retractor body <NUM> can define a proximal end portion 3f that is angularly offset from an adjacent portion <NUM> at an acute angle α1, as measured in a plane extending along the longitudinal and transverse directions L, T, which plane can be referred to as the "L-T plane". The adjacent portion <NUM> can be characterized as a portion of the body <NUM> that extends from the end portion 3f toward the opposite end <NUM> of the retractor body <NUM>. The retractor body <NUM> can alternatively or additionally define a distal end portion <NUM> that is angularly offset from the adjacent portion <NUM> at an acute angle a2 in the L-T plane. In embodiments where the retractor body <NUM> has proximal and distal end portions 3f, <NUM> that are angularly offset from the adjacent portion <NUM>, the acute offset angles a1, a2 can be substantially equivalent, as shown, or can be different from each other.

As shown in <FIG>, one or both of the proximal and distal end portions 3f, <NUM> can be flared outwardly along the lateral direction A so as to define a maximum lateral dimension A1, A2 that is greater than a maximum lateral dimension A3 of the adjacent portion <NUM>. In embodiments where both of the proximal and distal end portions 3f, <NUM> are flared outwardly along the lateral direction A, the maximum lateral dimensions A1, A2 of the end portions 3f, <NUM> can be substantially equivalent, as shown, or can be different from one another.

As shown in <FIG>, one or both of the proximal and distal end portions 3f, <NUM> can be both angularly offset from the adjacent portion <NUM> and flared outwardly along the lateral direction A relative to the adjacent portion <NUM>. For example, both of the proximal and distal end portions 3f, <NUM> can be angularly offset from the adjacent portion <NUM> at the same acute angle or different acute angles and can also be flared outwardly to define the same or different maximum lateral dimension. It should be appreciated that the retractor body <NUM> can have proximal and distal end portions 3f, <NUM> that are any combination of the foregoing (i.e., straight, angled, and flared).

Referring now to <FIG>, the proximal and distal body portions 3d, 3e can at least partially, and optionally entirely, circumferentially offset from each other. In such embodiments, the proximal body portion 3d can extend from the proximal end <NUM> in the distal direction D to the locking spring <NUM>, and the distal body portion 3e can extend from the locking spring <NUM> in the distal direction D to the distal end <NUM>. Additionally, in such embodiments, the locking spring <NUM> can include an interconnecting portion 16a that connects the proximal and distal body portions 3d, 3e together.

As shown in <FIG>, the retractor body <NUM> can include one or more features for increasing the flexibility of the respective body portions thereof. By way of non-limiting examples, the retractor body <NUM> can define apertures <NUM> extending therethrough along the transverse direction T, such as for facilitating plastic deformation in the L-T plane, such as for bending a proximal portion 3a of the body <NUM> out of the way once secured to the wall <NUM>, as described above with reference to <FIG>. For example, the apertures <NUM> can effectively define bend-enhancing regions of the retractor body <NUM>. Additionally or alternatively, one or both of the wings <NUM> can define an aperture <NUM> for increasing the flexibility of the wings <NUM>, such as for elastically deforming between the neutral and flexed configurations described above. One advantage of employing apertures <NUM>, <NUM> for increased flexibility is that stronger materials can be used to form the retractor body <NUM>. Moreover, the apertures <NUM> can be elliptical in shape, which can alleviated material fatigue from multiple bends imposed at or near the same location of the retractor body <NUM>. Additionally, at one or both of the proximal and distal ends <NUM>, <NUM>, the retractor body <NUM> can define an end formation <NUM> for connection to a wire, flexible tube, or other component or instrument of the surgical access system <NUM>. A non-limiting example of such an end formation <NUM> can include an aperture <NUM> and a prong <NUM> extending over the aperture <NUM>, such as along the longitudinal direction X.

It should be appreciated that the locking spring <NUM> of any of the foregoing embodiments can be provided at different longitudinal locations along the retractor body <NUM> to compensate for deflection responsive to the soft tissue engaged by the distal end <NUM> and/or other surrounding tissue in contact with the retractor <NUM>. For example, any combination of the retractors <NUM> described above with reference to <FIG> can be provided in a kit that includes multiple versions of each retractor <NUM>, wherein the respective locking springs <NUM> are located at different longitudinal locations along the retractor body <NUM>.

It should further be appreciated that the designs of the retractors <NUM> described above with reference to <FIG> allow more than one retractor <NUM>, such as two (<NUM>) or more retractors <NUM>, to be inserted within the working channel <NUM> and secured to the inner wall surface <NUM> for retracting soft tissue. When a second retractor <NUM> is inserted into a working channel <NUM> that already has a first retractor <NUM> attached thereto, the physician can select the second retractor <NUM> to be one in which its locking spring <NUM> will be longitudinally offset from that of the first retractor <NUM> when both are secured within the working channel <NUM>, thereby avoiding interference between the locking springs <NUM>. Additionally or alternatively, the physician can select the second retractor <NUM> to have the same design as the first, and can elect to insert the opposite end of the second retractor <NUM> into the channel <NUM> (i.e., can flip the second retractor <NUM> relative to the first retractor <NUM>) so that the locking springs <NUM> do not interfere with each other.

Referring now to <FIG>, in other embodiments, the attachment device <NUM> can include an attachment member <NUM> that is separate from and connectable to the retractor <NUM>, such as before, during, or after the retractor <NUM> is inserted through the working channel <NUM>. In such embodiments, the retractor <NUM> and the attachment member <NUM> can have complimentary mounting formations. For example, the attachment member <NUM> can include a slide formation, such as a slider <NUM>, that is configured to slidably engage a complimentary slide formation, such as a guide slot <NUM>, of the retractor body <NUM>. The guide slot <NUM> of the present embodiment guides translational, longitudinal movement of the slider <NUM> (and thus also the attachment member <NUM>) along the retractor body <NUM> into and out of the working channel <NUM> as needed. The slider <NUM> and the guide slot <NUM> preferably have complimentary geometries that allow the slider <NUM> to enter into the guide slot <NUM> and vacate the guide slot <NUM>, at least at one location of the guide slot <NUM>, such as at a proximal end thereof. For example, a proximal end of the guide slot <NUM> can have a widened portion or opening that allows entry and departure of the slider <NUM> therein, while the reminder of the guide slot <NUM> is configured to retain the slider <NUM> therein. A distal end of the guide slot <NUM> can effectively provide a physical stop that prevents the slider <NUM> (and thus also the attachment member <NUM>) from over-translating in the distal direction D.

Similar to the embodiments described above, the attachment member <NUM> includes a locking member, such as a locking spring <NUM>, which can be configured similarly as described above. The locking spring <NUM> can define one or more compliant wings, each of which can be referred to as a circumferential wall that extends circumferentially away from the slide formation <NUM> and is configured to be flexed inwardly toward the central axis <NUM> of the access member <NUM> when the locking member <NUM> is disposed in the working channel <NUM> to supply the locking force. When inside the working channel <NUM>, the locking spring <NUM> can be positioned so as to slide annularly between the outer surface <NUM> of the retractor body <NUM> and the inner surface <NUM> of the access member <NUM>. The slider <NUM> can extend inwardly along the transverse direction T (i.e., toward the central axis <NUM> of the access member <NUM>) from the locking spring <NUM> and into the guide slot <NUM>. In other embodiments, the slider <NUM> can extend transversely outwardly from the locking spring <NUM>, in which embodiments the retractor body <NUM> can be positioned annularly between the locking spring <NUM> and the inner wall surface <NUM>. The attachment member <NUM> includes a grip member, such as a proximal extension <NUM>, allowing the physician to manipulate the attachment member <NUM> along the longitudinal direction L relative to the retractor body <NUM>. It should be appreciated that the proximal extension <NUM> can be configured to be bent away from the central axis <NUM> and out of the way so as to reduce its profile in the proximal direction P, similar to the manner described above with reference to <FIG>.

The retractor body <NUM> of the present embodiment can be freely inserted through the working channel <NUM> to engage soft tissue, and once so engaged, can then receive the attachment member <NUM>, which can be advanced along the guide slot <NUM> along the distal direction D until the locking spring <NUM> resides at a desired longitudinal location within the working channel <NUM>, at which position it provides the locking force. The longitudinal position of the attachment member <NUM> can thereafter be adjusted as needed, such as to reduce deflection of the retractor responsive to surrounding tissue. Furthermore, if a subsequent adjustment to the engagement between the distal end <NUM> of the retractor body <NUM> and the soft tissue is desired, the attachment member <NUM> can be withdrawn proximally from the working channel <NUM> while optionally remaining engaged with the guide slot <NUM>, and can be re-translated within the working channel <NUM> as needed, such as after the adjustment to the soft tissue is complete. In this manner, the attachment member <NUM> can be withdrawn from the working channel <NUM> during re-adjustments to the soft tissue retraction, allowing the physician greater freedom to manipulate the retractor body <NUM> as needed.

Referring now to <FIG>, in other embodiments, the separate attachment member <NUM> and the retractor <NUM> can be configured for magnetic attachment to each other within the working channel <NUM>. For example, at least a portion of the locking spring <NUM> of the attachment member <NUM> can be constructed of a ferrous (e.g., magnetic) material, and the retractor <NUM> can include a series of magnets <NUM> for selective attachment to the attachment member <NUM> (or at least to the ferrous portion thereof). The attachment member <NUM>, including the locking spring <NUM> and the proximal extension <NUM> thereof, can otherwise be configured similarly as described above with reference to <FIG>. In the present embodiment, the attachment member <NUM> can be inserted within the working channel <NUM> and the retractor <NUM> can subsequently be inserted through the working channel <NUM> to engage and retract soft tissue. With soft tissue engaged, the physician can move the retractor <NUM> toward the inner wall surface <NUM> (and thus also toward the locking spring <NUM>) and can bring a select one of the magnets <NUM> into magnetic engagement with the locking spring <NUM> (or at least with the ferrous portion thereof), thereby attaching the retractor to the inner wall surface <NUM>. In additional embodiments, the retractor <NUM> can be constructed of a ferrous material and the locking spring <NUM> can carry one or more magnets. In further embodiments, the retractor <NUM> and the locking spring <NUM> can carry opposite polarity magnets for attachment therebetween.

Referring now to <FIG>, the surgical access system <NUM> can include an instrument <NUM> that is releasably coupled to the retractor body <NUM> for manipulating the retractor body <NUM>, such as to engage and retract soft tissue with the distal end <NUM> thereof. The instrument <NUM> includes a handle <NUM> that extends along a forward direction FD from a rear end <NUM> of the instrument <NUM> to a coupling mechanism <NUM> at a front end <NUM> of the instrument <NUM>. The coupling mechanism <NUM> releasably couples the instrument <NUM> to the retractor body <NUM>. For example, the coupling mechanism <NUM> can be configured to iterate between a coupled configuration (shown in <FIG>), in which the instrument <NUM> is rigidly coupled to the retractor body <NUM>, and a de-coupled configuration (shown in <FIG>), in which the instrument <NUM> is de-coupled and removable from the retractor body <NUM>, as described in more detail below.

The instrument <NUM> can also be configured to operate an attachment device <NUM> coupled to the retractor body <NUM>. As above, the attachment device <NUM> is configured to attach the retractor body <NUM> to the access member <NUM>, particularly to the inner wall surface <NUM> after the distal end <NUM> of the retractor body <NUM> has engaged the soft tissue to be retracted thereby. In the present embodiment, the attachment device <NUM> can have a proximal mount <NUM> and a distal mount <NUM> configured to respectively mount to the proximal and distal ends <NUM>, <NUM> of the access member wall <NUM>. The proximal mount <NUM> defines one or more mating surfaces <NUM> configured to engage one or more complimentary mating surfaces <NUM> defined at the front end <NUM> of the instrument <NUM>. The mating surfaces <NUM>, <NUM> can be aligned with the axial and longitudinal directions, respectively, allowing the instrument <NUM> to lift off of the proximal mount <NUM> along the longitudinal direction L when in the de-coupled configuration, as shown in <FIG>.

Referring now to <FIG>, the proximal and distal mounts <NUM>, <NUM> can each include an engagement member 320a, 320b configured to engage the access member <NUM>, such as at the proximal and distal ends <NUM>, <NUM> thereof, in a manner securing the attachment device <NUM> (and thus also the retractor body <NUM>) to the wall <NUM>. As shown, each of the engagement members 320a, 320b can be a hook configured to hook or otherwise latch to the respective proximal and distal ends <NUM>, <NUM> of the access member <NUM>. Additionally, at least one of the proximal and distal mounts <NUM>, <NUM>, such as the engagement member 320a, 320b thereof, can be configured to move between an unlocked configuration, in which the proximal and distal mounts <NUM>, <NUM> are longitudinally spaced from each other by a first distance L1, and a locked configuration in which the proximal and distal mounts are longitudinally spaced from each other by a second distance L2 that is less than the first distance L1. In particular, the second distance L2 corresponds to a distance between the proximal and distal ends <NUM>, <NUM> of the wall <NUM> along the axial direction X. In this manner, the proximal and distal mounts <NUM>, <NUM> can be configured to achieve a secure grip against the access member <NUM> for attaching the retractor body <NUM> thereto.

The surgical access system <NUM> includes an actuator <NUM> configured to actuate the at least one of the proximal and distal mounts <NUM>, <NUM> from the unlocked configuration to the locked configuration. For example, the proximal mount <NUM> can include a mount base <NUM> that is coupled to the engagement member 320a. In the illustrated embodiment, the actuator <NUM> extends between and connects the mount base <NUM> and the engagement member 320a together. Additionally, the actuator <NUM> is configured to actuate longitudinal movement of the engagement member 320a relative to the mount base <NUM> between the unlocked configuration and the locked configuration.

Referring now to <FIG>, the actuator <NUM> can comprise a bias mechanism <NUM> for biasing one or both of the proximal and distal mounts <NUM>, <NUM> into either the locked or unlocked configuration. In the illustrated embodiment, the bias mechanism <NUM> includes a spring assembly <NUM> that includes at least one spring <NUM>, such as a pair of springs <NUM>, that applies a bias force on the engagement member 320a away from the mount base <NUM> in a bias direction, such as the distal direction D, thereby actuating the engagement member 320a to the locked configuration. The spring assembly <NUM> can also include one or more spring guide members <NUM>, such as a pair of guide rods <NUM> or dowels, that extend centrally through the springs <NUM> as shown, and are configured to guide movement of the engagement member 320a toward and away from the mount base <NUM> along the longitudinal direction L.

The coupling mechanism <NUM> of the instrument <NUM> can be configured to move the actuator <NUM> in a manner causing, or at least contributing to, the actuation of one or both of the proximal and distal mounts <NUM>, <NUM> between the locked and unlocked configurations. For example, in the illustrated embodiment, the coupling mechanism <NUM> can include one or more movement members, such as a pair of arms <NUM>, that are configured to be operatively connected to the engagement member 320a of the proximal mount <NUM> in a manner causing movement of the engagement member 320a relative to the mount base <NUM>, as described in more detail below. As shown, the arms <NUM> can be spaced from each other along the lateral direction A and can be translatable relative to the handle <NUM>, such as along an arm translation direction having at least a directional component along the forward direction FD and/or a rearward direction RD opposite the forward direction FD. The arms <NUM> can ride along complimentary guide formations, such as guide slots <NUM> defined in a body <NUM> of the handle <NUM>. The guide slots <NUM> and the arms <NUM> can have complimentary dovetail geometries, as shown.

Referring now to <FIG>, the arms <NUM> can be coupled together by a yoke member <NUM>, which can also couple the arms <NUM> to a central arm <NUM>, that is biased along either the forward or rearward directions FD, RD. In the illustrated embodiment, the coupling mechanism <NUM> includes an arm bias member <NUM>, such as a spring, which can reside in a slot <NUM> defined centrally within the handle body <NUM>. The bias member <NUM> depicted is a compression spring that engages the central arm <NUM> so as to bias it and also arms <NUM> in the forward direction FD into the coupled configuration with the retractor body <NUM>. In the present embodiment, when in the coupled configuration, distal ends <NUM> of the arms <NUM> engage with and couple to the mount base <NUM>, which rigidly couples the instrument <NUM> to the retractor body <NUM>. As shown, when in the coupled configuration, the distal ends <NUM> of the arms <NUM> can extend within complimentary shaped receptacles <NUM> in the mount base <NUM> (see also <FIG>). The arms <NUM> are also configured to translate in the rearward direction RD to withdraw the distal end <NUM> of the arms <NUM> from the receptacles <NUM> of the mount base <NUM>, thereby moving the instrument <NUM> into the de-coupled configuration. In this manner, the arms <NUM> can be translated in the forward and rearward directions FD, RD to iterate the coupling mechanism <NUM> between the coupled and de-coupled configurations. Outer surfaces of the arms can include grip enhancement features <NUM>, such as serrations, for facilitating manual retraction of the arms <NUM>. As shown in <FIG>, when the distal ends <NUM> of the arms <NUM> are remote from the receptacles <NUM> of the mount base <NUM>, the instrument <NUM> can be moved away from the attachment device <NUM>, which remains attached to the access member <NUM>.

Referring now to <FIG>, while the coupling mechanism <NUM> is in the coupled configuration with the mount base <NUM>, the instrument <NUM> can also be configured to engage the actuator <NUM> for moving the engagement member 320a relative to the mount base <NUM>, such as to the unlocked configuration. As shown, the central arm <NUM> can be operationally connected to a return member <NUM> of the bias mechanism <NUM>. The return member <NUM> is configured to move the engagement member 320a toward the mount base <NUM> in a direction opposite the bias direction, such as the proximal direction P opposite the distal direction D, so as to move the engagement member 320a to the unlocked configuration. The return member <NUM> can be an elongated member extending proximally from the engagement member 320a of the proximal mount <NUM> and through an opening <NUM> at the front end <NUM> of the instrument <NUM> and into a chamber <NUM> defined within the handle body <NUM>. The opening <NUM> can be defined between the handle body <NUM> and the base member <NUM> of the proximal mount <NUM>. The return member <NUM> can be monolithic with the engagement member 320a, as shown, or can alternatively be a separate member that is connected to the engagement member 320a.

The instrument <NUM> can include a connector <NUM> that connects the central arm <NUM> to the return member <NUM>. A front end 337a of the connector <NUM> can be configured to reside within a recess <NUM> defined by the return member <NUM> when the coupling mechanism <NUM> is in the coupled configuration, as shown. The front end 337a of the connector <NUM> and the recess <NUM> can have complimentary geometries such that the connector <NUM> retains the return member <NUM> in the unlocked configuration (against the bias force) when the front end 337a resides in the recess <NUM>. The instrument <NUM> can include a second actuator, such as a button <NUM>, configured to iterate the engagement member 320a of the proximal mount <NUM> between the locked and unlocked configurations. The button <NUM> can be configured to iterate between a first or neutral button position, in which the proximal mount <NUM> is in the locked configuration, and a second or depressed button position, in which the proximal mount <NUM> is in the unlocked configuration. In particular, the button <NUM> can be biased into one of the neutral and depressed button positions by a button bias member, such as a spring <NUM>, which can reside within a button spring receptacle <NUM> defined within the handle body <NUM>.

The button <NUM> can include one or more extensions or legs <NUM>, such as a pair of legs <NUM> that straddle the central arm <NUM>. At least one of the button legs <NUM> can include a cam protrusion <NUM> configured to ride along a complimentary groove <NUM> defined in the connector <NUM>. The connector <NUM> can be pivotably coupled to the central arm <NUM> via a pin joint <NUM>, so that as the button <NUM> is depressed, the cam <NUM> and groove <NUM> engagement pivots the connector <NUM> about the pin joint <NUM> so that the front end 337a of the connector <NUM> pulls the return member <NUM> in the proximal direction P against the bias force, thereby moving the engagement member 320a of the proximal mount <NUM> to the unlocked configuration. Additionally, as the button <NUM> iterates to its neutral position, the cam <NUM> and groove <NUM> engagement pivots the connector <NUM> oppositely about the pin joint <NUM>, thereby allowing the bias mechanism <NUM> to return the engagement member 320a to the locked configuration. Thus, the physician can operate the button <NUM> to move the proximal mount <NUM> between the locked and unlocked configurations as needed. It should be appreciated that the front end 337a of the connector <NUM> is configured to be remote from the receptacle <NUM> in the rearward direction RD when the instrument <NUM> is in the de-coupled configuration. Thus, moving the arms <NUM> in the forward and rearward directions FD, RD to iterate the coupling mechanism <NUM> between the coupled and de-coupled configurations engages and disengages the connector <NUM> from the return member <NUM>.

Operation of the instrument <NUM> to retract soft tissue at the treatment site will now be described. The instrument <NUM> can be used to insert the retractor body <NUM> through the working channel <NUM> to engage and retract soft tissue. In particular, the physician can manipulate the retractor body <NUM> to engage and retract soft tissue via the handle <NUM>. Once the soft tissue is engaged, the physician can use the instrument <NUM> to pull the soft tissue toward the wall <NUM>. The design of the attachment device <NUM> allows the physician to elect whether to first secure the proximal or distal mount <NUM>, <NUM> to the respective proximal or distal end <NUM>, <NUM> of the access member <NUM>. The elected mount <NUM>, <NUM> is secured to the respective end <NUM>, <NUM> of the access member <NUM> by engaging the end <NUM>, <NUM> with the hook 320a, 320b of the mount <NUM>, <NUM>. To secure the elected mount <NUM>, <NUM> to the respective end <NUM>, <NUM> of the access member <NUM>, the physician can depress the button <NUM> to move the engagement member <NUM> of the proximal mount <NUM> to the unlocked configuration. It should be appreciated that, with one of the mounts <NUM>, <NUM> secured, the physician can optionally use the secured mount <NUM>, <NUM> as a pivot or fulcrum to bring the other of the proximal and distal mounts <NUM>, <NUM> into alignment with the respective end <NUM>, <NUM> of the access member <NUM>. With both mounts <NUM>, <NUM> aligned with the ends <NUM>, <NUM> of the access member <NUM>, the physician can then release the button <NUM>, thereby allowing the bias mechanism <NUM> to bias the proximal engagement member 320a away from the mount base <NUM> in a manner reducing the longitudinal distance between the mounts <NUM>, <NUM> until both mounts <NUM>, <NUM> are secured to the ends <NUM>, <NUM> of the access member <NUM> in the locked configuration.

Referring now to <FIG>, the attachment device <NUM> can be configured to allow translation of the retractor body <NUM> along the longitudinal direction L relative to the access member <NUM> while attached to the wall <NUM>. For example, the attachment device <NUM> can include one or more elongate member <NUM>, such as a pair of rods, that extend within the working channel <NUM> from the proximal mount <NUM> to the distal mount <NUM>. The rods <NUM> are spaced from each other along the lateral direction A so that the retractor body <NUM> can extend between the rods <NUM>. One or both of the proximal and distal mounts <NUM>, <NUM> can include guide features, such as guide shoes <NUM> that engage the lateral sides <NUM>, <NUM> of the retractor body <NUM>. For example, the guide shoes <NUM> and the lateral sides <NUM>, <NUM> of the retractor body <NUM> can have complimentary shapes to guide translation of the retractor body <NUM> along the longitudinal direction L. One or both of the proximal and distal mounts <NUM>, <NUM> can also define a guide channel <NUM> having a complimentary geometry with the retractor body <NUM> for further guiding its translational movement <NUM> along the longitudinal direction L.

The attachment device <NUM> can include a retention mechanism for retaining the relative longitudinal position between the retractor body <NUM> and the attachment device <NUM>. For example, as shown in <FIG>, the base member <NUM> can include a flexible tab or pawl <NUM> having a tooth <NUM> at a distal, free end of the pawl <NUM>. The tooth <NUM> is configured to successively engage a longitudinal series of complimentary ratchet grooves <NUM> defined in the outer surface <NUM> of the retractor body <NUM> as the retractor body <NUM> translates relative to the mount base <NUM>. The tooth <NUM> and ratchet grooves <NUM> can have complimentary geometries that allow the physician to manually translate the retractor body <NUM> longitudinally relative to the attachment device <NUM> as desired, yet provide sufficient resistance to retain the relative longitudinal position between the retractor body <NUM> and the attachment device <NUM> after the physician ceases manipulating the retractor body <NUM>. It should be appreciated that the complimentary geometries of the tooth <NUM> and ratchet grooves <NUM> can be tailored as needed to provide a desired amount of resistance to relative longitudinal movement between the attachment device <NUM> and the retractor body <NUM>.

Referring now to <FIG>, another embodiment of the surgical access system <NUM> is shown that includes an instrument <NUM> that is releasably coupled to the retractor body <NUM>. As with the embodiments described above, the instrument <NUM> is configured to iterate between a coupled configuration, in which the instrument is coupled to the retractor body <NUM>, and a de-coupled configuration, in which the instrument <NUM> is de-coupled and removable from the retractor body <NUM>. For the sake of brevity, the following disclosure will focus on differences between this embodiment and the embodiment described above with reference to <FIG>.

In the present embodiment, the retractor body <NUM> carries an attachment device <NUM> that is operable between a locked configuration and an unlocked configuration independent of operation of the instrument <NUM>. As shown, the attachment device <NUM> includes proximal and distal mounts <NUM>, <NUM> that can each have a hook-like geometry for engaging the proximal end distal ends <NUM>, <NUM> of the access member <NUM>. An elongate actuator <NUM> extends proximally from the distal mount <NUM>, through a receptacle defined by the proximal mount <NUM>, and to a control member <NUM> that is spaced from the proximal mount <NUM> in the proximal direction P. The elongate actuator <NUM> can be a rod that can be rigidly coupled to the distal mount <NUM> and configured to slide the distal mount <NUM> along the retractor body <NUM> and relative to the proximal mount <NUM> so as to adjust the longitudinal distance between the proximal and distal mounts <NUM>, <NUM> as needed to attach to the access member <NUM>. The control member <NUM> can be a finger tab allowing push-push operation of the elongate actuator <NUM> along the longitudinal direction L.

The instrument <NUM> can be used to insert the retractor body <NUM> through the working channel <NUM> to engage and retract soft tissue. As above, once the soft tissue is engaged, the physician can use the instrument <NUM> to pull the soft tissue toward the wall <NUM>, electing to secure either the proximal or distal mount <NUM>, <NUM> to the respective proximal or distal end <NUM>, <NUM> of the access member <NUM> first by hooking the end <NUM>, <NUM> with the hook of the mount <NUM>, <NUM>. From this position, the physician can align the other of the proximal and distal mounts <NUM>, <NUM> with the respective end <NUM>, <NUM> of the access member <NUM>, and then operate the control member <NUM> to reduce the longitudinal distance between the mounts <NUM>, <NUM> until both mounts <NUM>, <NUM> are secured to the ends <NUM>, <NUM> of the access member <NUM> in the locked configuration. The proximal and distal mounts <NUM>, <NUM> preferably each define a guide channel <NUM> (shown in <FIG>) having a complimentary geometry with the retractor body <NUM> for further guiding translational movement of the retractor body <NUM> along the longitudinal direction L, at least after the instrument <NUM> is de-coupled from the attachment device <NUM>.

Referring now to <FIG>, the instrument <NUM> includes a coupling mechanism <NUM> that couples directly to the retractor body <NUM>. In particular, the instrument <NUM> has an instrument body <NUM> having a mounting sleeve <NUM> at a front end <NUM> thereof. The mounting sleeve <NUM> defines a receptacle <NUM> that is configured to receive a proximal portion of the retractor body <NUM> along the proximal direction P. Additionally, the coupling mechanism <NUM> includes a locking pin <NUM> that resides within a pin receptacle <NUM> defined within the instrument body <NUM> along a pin axis <NUM>. The pin axis <NUM> can be oriented along the transverse direction T. The pin receptacle <NUM> is aligned with a locking hole <NUM> defined within a front portion of the mounting sleeve <NUM>. In the present embodiment, the retractor body <NUM> defines a locking aperture <NUM> extending from the inner surface <NUM> to the outer surface <NUM> along the transverse direction T. The proximal end <NUM> of the retractor body <NUM> can be inserted along the proximal direction P within the mounting sleeve <NUM> until the locking aperture <NUM> is aligned with the locking pin <NUM>. Once aligned, the locking pin <NUM> can be advanced from a de-coupled configuration, in which the pin <NUM> is remote from the locking aperture <NUM>, to a coupled configuration, in which the locking pin <NUM> extends through the locking aperture <NUM> of the retractor body <NUM> and into the locking hole <NUM>.

The locking pin <NUM> can be iterated between the coupled and de-coupled configurations by movement of a button <NUM> between a first button position and a second button position along a button axis <NUM>. The button axis <NUM> can be oriented at an angle relative to the pin axis <NUM>. As shown, the button <NUM> and the pin <NUM> can define a complimentary camming mechanism, which can include a side pin or protrusion extending laterally from the pin <NUM> and into a cam groove <NUM> defined in a body <NUM> of the button <NUM>. In this manner, iterative motion of the button <NUM> along its axis <NUM> can drive iterative motion of the locking pin <NUM> along its axis <NUM> between the coupled and de-coupled configurations. It should be appreciated that a biasing member, such as a spring, can extend between the button <NUM> and the instrument body <NUM>, which can be operated in complimentary fashion with the camming mechanism to effectively toggle the locking pin <NUM> between the coupled and de-coupled configurations.

Referring now to <FIG>, the instrument <NUM> described above can be configured to employ a tensile actuator, such as a suture member <NUM>, for pulling the distal mount <NUM> toward the proximal mount <NUM> and moving the attachment device <NUM> into the locked configuration. In such embodiments, the distal mount <NUM> can include one or more receiving formations for receiving at least a portion of the suture member <NUM>. Such receiving formations can include one or more apertures <NUM> defined by the distal mount <NUM>, such as a pair of apertures <NUM> that are spaced apart from each other along the lateral direction A. The pair of apertures <NUM> can extend through a rear portion of the distal mount <NUM> along a direction having at least a directional component along the transverse direction T. The suture member <NUM> can be threaded through the apertures <NUM> so as to define one or more suture tails <NUM>, such as a pair of suture tails <NUM>, which can be operatively coupled to the proximal mount <NUM>. The proximal mount <NUM> can include one or more additional receiving formations <NUM>, such as suture channels, cleats, and the like, for receiving and securing the one or more suture tails <NUM> thereto. The instrument <NUM> can also include additional receiving formations, such as channels, cleats, and the like, for receiving and/or securing free end(s) of the one or more suture tails <NUM> extending from the proximal mount <NUM>, allowing the physician to tighten the one or more suture tails <NUM> relative to the instrument <NUM> in a secure, yet unlocked configuration.

As shown in <FIG>, the one or more receiving formations <NUM> of the proximal mount <NUM> can be configured so that the respective suture tail <NUM> can lock therewith via friction. The suture member <NUM> can extend from a first end 439a thereof, through a first receiving formation <NUM> at the proximal mount <NUM>, alongside the retractor body <NUM> along the longitudinal direction L, through the apertures <NUM> in the distal mount <NUM>, alongside the retractor body <NUM> again and back toward the proximal mount <NUM>, through a second receiving formation <NUM> at the proximal mount <NUM>, and to a second end 439b of the suture member <NUM> opposite the first end 439a. In this manner, the suture tail <NUM> adjacent the second end 439b can be manipulated by the physician to tension the suture member <NUM> to pull the distal mount <NUM> toward the proximal mount <NUM>, thereby moving the attachment device <NUM> into the locked configuration. Once in the locked configuration, the suture tail <NUM> adjacent the second end 439b can be secured to the second receiving formation <NUM>, thereby locking the attachment device <NUM> in the locked configuration. It should be appreciated that the first end 439a of the suture member <NUM> can be tied or otherwise configured in a knot for retaining the first end 439a at the first receiving formation <NUM>. Moreover, the second end 439b of the suture member <NUM> can optionally be coupled to a pull member, such as a rigid ring or loop, for assisting the physician in tensioning the suture member <NUM>.

In the unlocked configuration, the instrument <NUM> can be used to insert the retractor body <NUM> through the working channel <NUM> to engage and retract soft tissue. Once the soft tissue is engaged, the physician can use the instrument <NUM> to pull the soft tissue toward the wall <NUM>. During this process, the physician can elect to secure at least one of the proximal and distal mounts <NUM>, <NUM> to the respective proximal and/or distal end <NUM>, <NUM> of the access member <NUM>, such as by hooking the end with the hook of the mount <NUM>, <NUM>. As above, the design of the attachment device <NUM> allows the physician to hook either the proximal mount <NUM> or the distal mount <NUM> to the respective end <NUM>, <NUM> first. From this position, the physician can align the other of the proximal and distal mounts <NUM>, <NUM> with its respective end of the access member <NUM>, and then apply a tensile force to the suture member <NUM>, such as by pulling the free suture tail <NUM> adjacent the second end 439b, until the proximal and distal mounts <NUM>, <NUM> are secured to the ends <NUM>, <NUM> of the access member <NUM> in the locked configuration, as shown in <FIG>. From this position, the physician can affix the free suture tail <NUM> to the second receiving formation <NUM> of the proximal mount <NUM> (so that both suture <NUM> are secured to the proximal mount <NUM>), thereby maintaining the mounts <NUM>, <NUM> in the locked configuration. The physician can also detach one or both of the ends 439a, b of the suture tails <NUM> from the receiving formations of the instrument <NUM>, allowing the instrument <NUM> to de-couple from the proximal mount <NUM> with the proximal and distal mounts <NUM>, <NUM> secured in the locked configuration.

Similarly as described above, the proximal and distal mounts <NUM>, <NUM> preferably each define a guide channel having a complimentary geometry with the retractor body <NUM> for guiding translational movement of the retractor body <NUM> along the longitudinal direction L relative to the mounts <NUM>, <NUM> after the instrument <NUM> is de-coupled from the proximal mount <NUM>. For example, as shown in <FIG>, one or both of the proximal and distal mounts <NUM>, <NUM> can define a channel <NUM> with keystone-like channel sidewalls <NUM> that retains the retractor body <NUM> within the channel <NUM> while allowing longitudinal translation of the retractor body <NUM> relative to the mount. Additionally, the outer surface <NUM> of the retractor body <NUM> can optionally define a longitudinal channel or groove <NUM> configured to receive the suture member <NUM>. It should also be appreciated that the instrument <NUM> of the present embodiment can employ the same or a similar coupling mechanism as the coupling mechanism <NUM> described above with reference to <FIG> for selectively coupling directly to and de-coupling from the retractor body <NUM>. In such embodiments, the proximal mount <NUM> can be rigidly affixed to the mounting sleeve <NUM> of the coupling mechanism. It should further be appreciated that in additional embodiments the instrument <NUM> described above with reference to <FIG> can be configured to employ a tensile actuator that is alternatively an elastic member, such as an elastic band, by way of a non-limiting example.

Referring now to <FIG>, the surgical access system <NUM> can include an attachment device <NUM> having proximal and distal mounts <NUM>, <NUM> and employing a retention mechanism, such as a ratchet or ratchet-like mechanism, for securing the mounts <NUM>, <NUM> in the locked configuration to the access member <NUM>. Similar to the embodiments described above with reference to <FIG>, one or both of the proximal and distal mounts <NUM>, <NUM> of the present embodiment are configured to iterate between unlocked and locked configurations. Additionally, as above, the mounts <NUM>, <NUM> include engagement members 720a, 720b, such as hooks, that are configured to hook, latch, or otherwise secure to the respective proximal and distal ends <NUM>, <NUM> of the access member <NUM> when in the locked configuration. For the sake of brevity, the following disclosure will focus on differences between the present embodiment and the embodiments described above with reference to <FIG>.

As shown in <FIG>, each of the proximal and distal mounts <NUM>, <NUM> can include an elongate body portion <NUM> that is elongated along the longitudinal direction L and conformally shaped with the outer surface <NUM> of the retractor body <NUM> for guiding translational movement of the retractor body <NUM> relative to the mounts <NUM>, <NUM>. The elongate body portions 719a, 719b are configured to extend within the working channel <NUM> and reside between the retractor body <NUM> and the inner wall surface <NUM> of the access member <NUM>. The proximal mount <NUM> can also include an elongate handle portion <NUM> that extends from the elongate body portion 719a and is configured to allow a physician to manipulate the retractor body <NUM> for engaging soft tissue at the treatment site. For example, the elongate handle portion <NUM> can be configured for manipulation by the physician's index finger. As shown in <FIG>, the handle portion <NUM> can have a circular shape in other embodiments. In yet other embodiments, the handle portion <NUM> can be configured to deflect between at least one of the elongate (<FIG>) and circular (<FIG>) configurations to the other configuration.

The attachment device <NUM> includes an elongate actuator <NUM> that extends proximally from the distal mount <NUM>, through and/or alongside the proximal mount <NUM>, and to a control member <NUM> that is spaced from the proximal mount <NUM> in the proximal direction P. As shown, the elongate actuator <NUM> can be a pair of rods <NUM> that can be rigidly coupled to the distal mount <NUM> and configured to translate the distal mount <NUM> along the retractor body <NUM> and relative to the proximal mount <NUM> to iterate the mounts <NUM>, <NUM> between the locked and unlocked configurations, similarly as described above with reference to <FIG>. As above, the control member <NUM> can be a finger tab allowing push-push operation of the actuator rods <NUM> along the longitudinal direction L. For example, the control member <NUM> can be configured for manipulation by the physician's thumb, while the handle portion <NUM> is configured for manipulation by the physician's index finger. As shown in <FIG>, the actuator rods <NUM> can extend through guide channels <NUM> defined in the outer surface <NUM> of the retractor body <NUM>. The actuation rods <NUM> can also extend through complimentary guide channels <NUM> defined by the elongate body portion 719a of the proximal mount <NUM>. In this manner, the actuator rods <NUM> can translate the distal mount <NUM> relative to the proximal mount <NUM>.

Referring now to <FIG>, the retractor body <NUM> and the proximal and distal mounts <NUM>, <NUM> can include guide features for guiding translational movement of the retractor body <NUM> relative to the mounts <NUM>, <NUM> and vice versa, such as for translating the retractor body <NUM> relative to the access member <NUM>. For example, the retractor body <NUM> can define a slot <NUM> elongate along the longitudinal direction L. The mounts <NUM>, <NUM> can each include slide members <NUM> that extend from the respective elongate body portion 719a, 719b and within the slot <NUM> and are configured to ride longitudinally along the slot. Within the slot <NUM>, the retractor body <NUM> can define side walls <NUM> that are canted inwardly toward each other, and the slide members <NUM> can have a flared geometry that is complimentary with the canted geometry of the side walls <NUM> in dovetail fashion. In this manner, the sidewalls <NUM> can retain the slide members <NUM> within the slot <NUM>, thus also retaining the proximal and distal mounts <NUM>, <NUM> in engagement with the outer surface <NUM> of the retractor body <NUM>.

Referring now to <FIG>, the retention mechanism for selectively retaining the relative longitudinal position between the proximal and distal mounts <NUM>, <NUM> will now be described. The retractor body <NUM> can define, for example, a series of ratchet grooves <NUM> that are arranged longitudinally alongside the slot <NUM> and are configured to engage at least one complimentary ratchet tooth <NUM> of at least one of the proximal and distal mounts <NUM>, <NUM>. The ratchet grooves <NUM> can be defined in the outer surface <NUM> of the retractor body <NUM>, and can also be at least partially defined by the sidewalls <NUM> within the slot <NUM>.

As shown in <FIG>, the ratchet tooth <NUM> can extend from a flexible tab <NUM>, which can also be referred to as a "pawl", and which can be defined by the elongate body portion 719a of the proximal mount <NUM>. The ratchet tooth <NUM> is configured to selectively engage at least one and up to each of the ratchet grooves <NUM> in succession as the proximal mount <NUM> translates longitudinally relative to the retractor body <NUM>. The ratchet tooth <NUM> can be located at a first end <NUM> of the pawl <NUM> opposite a second end <NUM> of the pawl <NUM>. The second end <NUM> can include the hook 320a of the proximal mount <NUM>. The pawl <NUM> can reside within a recess of cutout <NUM> defined by the elongate body portion 719a. The pawl <NUM> can be connected to a remainder of the elongate body portion 719a by a pair of arms <NUM> opposite each other along the lateral direction A. The pair of arms <NUM> can provide the pawl <NUM> with flexibility for rotation along a plane defined by the longitudinal and transverse directions T. In this manner, the pawl <NUM> can be configured to iterate between a neutral or engaged configuration (as shown in <FIG>), in which the tooth <NUM> resides within one of the ratchet grooves <NUM> so as to retain a relative longitudinal position between the proximal mount <NUM> and the retractor body <NUM>, and a flexed or disengaged configuration, in which the tooth <NUM> is remote from each of the ratchet grooves <NUM>.

The tooth <NUM> and ratchet grooves <NUM> can have complimentary geometries that provide substantially equivalent resistance to proximal or distal movement of the proximal mount <NUM> relative to the retractor body <NUM>. It should be appreciated that the complimentary geometries of the tooth <NUM> and ratchet grooves <NUM> can be tailored as needed to provide a desired amount of resistance to relative longitudinal movement between the proximal mount <NUM> and the retractor body <NUM>. In other embodiments, the tooth <NUM> and ratchet grooves <NUM> can have complimentary geometries that prevent proximal movement of the proximal mount <NUM> relative to the retractor body <NUM> in the engaged configuration. In such embodiments, the pawl <NUM> can optionally include a disengagement feature for manually rotating the pawl <NUM> to the disengaged configuration. It should be appreciated that the retention mechanism of the foregoing embodiments can provide audible and/or tactile feedback regarding relative longitudinal movement between the proximal mount <NUM> and the retractor body <NUM> as the tooth <NUM> successively "clicks" into and out of the ratchet grooves <NUM>. It should be appreciated that in other embodiments, controlled movement of the proximal and distal mounts <NUM>, <NUM> relative to one another can employed in a friction-based retention mechanism.

Operation of the retractor <NUM> of the present embodiment will now be described. The handle portion <NUM> can be used to insert the retractor body <NUM> through the working channel <NUM> to engage and retract soft tissue. Once the soft tissue is engaged, the physician can use the handle portion <NUM> to pull the soft tissue toward the wall <NUM>, electing to secure either the proximal or distal mount <NUM>, <NUM> to the respective proximal or distal end <NUM>, <NUM> of the access member <NUM> first by hooking the end <NUM>, <NUM> with the hook of the mount <NUM>, <NUM>. From this position, the physician can align the other of the proximal and distal mounts <NUM>, <NUM> with the respective end <NUM>, <NUM> of the access member <NUM>, and then operate the control member <NUM> to reduce the longitudinal distance between the mounts <NUM>, <NUM>, thereby causing the ratchet tooth <NUM> to sequentially engage the ratchet grooves <NUM>, until both mounts <NUM>, <NUM> are secured to the ends <NUM>, <NUM> of the access member <NUM> in the locked configuration.

It should be appreciated that each of the embodiments described above with reference to <FIG>, in which the respective attachment devices <NUM>, <NUM>, <NUM> attach to the ends <NUM>, <NUM> of the access member <NUM>, allow multiple retractors <NUM> to be attached concurrently to various select circumferential locations of the access member <NUM>.

Referring now to <FIG>, the surgical access system <NUM> can include a suction attachment device <NUM> configured to selectively attach the retractor body <NUM> to a circumferential portion of the inner wall <NUM> of the access member <NUM>. For example, the retractor body <NUM> can define an internal chamber <NUM> in fluid communication with a plurality of vacuum ports <NUM> defined in the outer surface <NUM> of the retractor body <NUM>. The internal chamber <NUM> is also in fluid communication with a proximal port <NUM> that is connectable to a tube <NUM> that is in turn connectable to a vacuum source <NUM>, such as a vacuum pump. A plurality of ring seals <NUM> are located in the vacuum ports <NUM> and are configured to provide sealing engagement with the inner wall surface <NUM> when the ring seals <NUM> are brought into contact with the inner wall surface <NUM> and the vacuum source <NUM> supplies vacuum pressure to the internal chamber <NUM> and thus also to the vacuum ports <NUM>. The suction attachment device <NUM> can be configured to provide a tailored sufficient suction force allowing the retractor body <NUM> to translate at least longitudinally relative to the access member <NUM> while the retractor body <NUM> remains attached to the access member <NUM> via the suction attachment device <NUM>. It should be appreciated that the present embodiment allows multiple retractors <NUM> to be attached via suction concurrently to various select circumferential locations of the inner wall surface <NUM>.

Referring now to <FIG>, the surgical access system <NUM> can include an attachment device <NUM> that employs mating engagement between protrusions <NUM> and openings <NUM> for selectively attaching the retractor body <NUM> to a circumferential portion of the access member <NUM>. For example, at least one of the inner wall surface <NUM> and the retractor body <NUM> can define one or more openings <NUM>, and the other of the inner wall surface <NUM> and the retractor body <NUM> can comprise one or more protrusions <NUM> that are complimentary with the one or more openings <NUM>. Stated differently, the one or more protrusions <NUM> are configured for insertion within the one or more openings <NUM> so as to couple the retractor body <NUM> to the access member <NUM>.

As shown in <FIG>, the wall <NUM> of the access member <NUM> can define an array <NUM> of openings <NUM> and the retractor <NUM> can include a series of protrusions <NUM> for engagement within selective ones of the openings <NUM>. The protrusions <NUM> can be defined by, and monolithic with, the retractor body <NUM>, or can be carried by an insert connectible with the retractor body <NUM>. The protrusions <NUM> extend outwardly from the outer surface <NUM> of the retractor body <NUM> and are aligned with each other along the longitudinal direction L. The openings <NUM> can each extend outwardly into the wall from the inner surface <NUM> thereof. The array <NUM> can include one or more columns <NUM> of openings <NUM> and one or more rows <NUM> of openings <NUM>. In each column <NUM>, the openings can be aligned with each other along the longitudinal direction L. Thus, each column <NUM> can be characterized as defining a longitudinally aligned subset of the openings <NUM> in the array <NUM>. The columns <NUM> are circumferentially spaced from each other along the wall <NUM>. In each row <NUM>, the openings <NUM> can be aligned along the lateral direction A. Thus, each row <NUM> can be characterized as defining a laterally aligned subset of the openings <NUM> in the array <NUM>. The rows <NUM> are spaced from each other along the axial direction X of the access member <NUM> (and also along the longitudinal direction L of the retractor <NUM> when the retractor <NUM> is attached to the access member <NUM>). In the embodiment illustrated in <FIG>, the protrusions <NUM> are configured for insertion within any one of columns <NUM> to selectively attach the retractor body <NUM> to a circumferential portion of the access member <NUM>. It should be appreciated that the retractor <NUM> can have fewer protrusions <NUM> than the number of openings <NUM> in a column <NUM>. In such embodiments, the retractor <NUM> can also be selectively attached to the access member <NUM> at a select depth (i.e., select longitudinal location).

The protrusions <NUM> can optionally define a stem <NUM> extending from the retractor <NUM> and a head <NUM> located at an outer end of the stem <NUM> and being wider than the stem <NUM>. As shown in <FIG>, the openings <NUM> can extend radially through the wall <NUM> from the inner wall surface <NUM> to the outer wall surface <NUM>. In such embodiments, the protrusions <NUM> can be configured such that the stems <NUM> extend through the openings <NUM> and at least portions of the heads <NUM> are located radially outward of the outer wall surface <NUM> when the retractor body <NUM> is attached to the access member <NUM>. As shown, the stems <NUM> can be sufficiently long so that the entire head <NUM> is located radially outward of the wall <NUM>. In such embodiments, at least a portion of the head <NUM> can overlap at least a portion of the wall <NUM> along the axial direction X of the access member <NUM> (and thus also along the longitudinal direction L of the retractor <NUM>) when the retractor <NUM> is attached to the access member wall <NUM>. Thus, the protrusions <NUM> and the openings <NUM> can be cooperatively configured to resist inadvertent detachment of the retractor <NUM> from the access member wall <NUM> along the transverse direction T.

In other embodiments, as shown in <FIG>, the openings <NUM> can extend from the inner wall surface <NUM> and terminate at a location radially inward of the outer wall surface <NUM>. In such embodiments, the opening <NUM> can include an axial receptacle <NUM> configured to receive a portion of the mating head <NUM>, such that at least a portion of the head <NUM> overlaps at least a portion of the wall <NUM> along the axial and longitudinal directions X, L, respectively, as above. It should be appreciated that other complimentary protrusion <NUM> and opening <NUM> geometries for providing sturdy, selective attachment of the retractor <NUM> to the access member wall <NUM> are within the scope of the present disclosure. It should also be appreciated that in other embodiments the protrusions <NUM> can extend inwardly from the inner wall surface <NUM> of the access member <NUM> and the openings <NUM> can be defined in the retractor body <NUM>.

In a surgical procedure using the surgical access system <NUM> of the present embodiment, the physician can insert the retractor body <NUM> through the working channel <NUM> to engage and retract soft tissue. Once the soft tissue is engaged, the physician can manipulate the proximal end <NUM> of the retractor <NUM> to pull the soft tissue toward the wall <NUM>. In particular, the physician can identify the column <NUM> of openings <NUM> in the inner wall surface <NUM> that is in substantial radial alignment with the desired direction of retraction for coupling with the protrusions <NUM> of the retractor <NUM>. The physician can then insert the protrusions <NUM> of the retractor <NUM> within the select openings <NUM> of the column <NUM> at the desired longitudinal position of the retractor <NUM> relative to the access member <NUM>, thereby affixing the retractor <NUM> to the inner wall surface <NUM> at the select circumferential and longitudinal positions of the inner wall surface <NUM>. It should be appreciated that multiple retractors <NUM> can be affixed to the inner wall surface <NUM> in like manner for retracting soft tissue as needed.

Referring now to <FIG>, an additional embodiment is shown in which one or more protrusions <NUM> extend proximally from a proximal surface <NUM> of the access member <NUM>. The proximal surface <NUM> can define the proximal end <NUM> of the access member <NUM>. In such embodiments, the one or more protrusions <NUM> can include a plurality of protrusions <NUM> spaced circumferentially from one another along the proximal surface <NUM>. The proximal surface <NUM> can be defined by a flange <NUM> at the proximal end <NUM> of the access member <NUM>. In the present embodiment, the retractor body <NUM> defines one or more openings <NUM> extending therethrough from the inner surface <NUM> to the outer surface <NUM>. Particularly, the retractor body <NUM> of the present embodiment can be either pre-bent or bendable such that a first or proximal portion 3a of the retractor body <NUM> is angularly offset relative to a second or distal portion 3b of the retractor body <NUM>, as described above with reference to <FIG>. The proximal portion 3a defines at least one opening <NUM> that extends along the axial direction X and can thus be mated with a select one of the protrusions <NUM> for attaching the retractor body <NUM> to the associated select circumferential portion of the access member <NUM>. As shown, the proximal and distal portions 3a, 3b of the retractor body <NUM> can be angularly offset from each other in the L-T plane, such that the distal portion 3b extends through the working channel <NUM> substantially along the axial direction X while the proximal portion 3a is elongate along the radial direction R (or at least along a direction having a directional component along the radial direction R).

In embodiments where the retractor body <NUM> is pre-bent, the proximal portion 3a defines a single opening <NUM>. In embodiments where the retractor body <NUM> is bendable, the retractor body <NUM> can define a plurality of openings <NUM> spaced in series along the longitudinal direction L, allowing the physician to bend the retractor body <NUM> at a select longitudinal location to define the respective lengths of the proximal and distal portions 3a, 3b, thereby defining the insertion depth of the distal portion 3b when attached to the retractor body <NUM>. It should be appreciated that, as above, the protrusions <NUM> can have a stem <NUM> and a head <NUM>, and can be cooperatively configured with the opening <NUM> so that the head <NUM> can overlap at least a portion of the retractor body <NUM> along the radial direction R when the retractor body <NUM> is attached to the access member <NUM>. Such overlap can increase the sturdiness of attachment between the retractor body <NUM> and the access member <NUM>.

During use of the embodiment shown in <FIG>, the physician can identify the protrusion <NUM> on the proximal surface <NUM> in substantial radial alignment with the desired direction of retraction for coupling with the opening <NUM> of the retractor <NUM>. The physician can insert the retractor body <NUM> through the working channel <NUM> and engage and retract soft tissue in the radial direction R, bringing the distal portion 3b of the retractor body <NUM> toward the inner wall surface. In embodiments where the retractor body <NUM> is pre-bent, the foregoing step also brings the opening <NUM> in the bent proximal portion 3a into alignment with the selected protrusion <NUM>. In embodiments where the retractor body <NUM> is bendable, the physician can bend the retractor body <NUM> at the select longitudinal location to provide the distal portion 3b with the desired axial depth relative to the access member <NUM>. In either embodiment, with the distal portion 3b engaged with soft tissue and moved toward the select circumferential portion of the inner wall surface <NUM>, the physician can move the proximal portion 3a so that the opening <NUM> receives the select protrusion <NUM>, thereby attaching the retractor body <NUM> to the access member <NUM> as desired. It should be appreciated that multiple retractors <NUM> can be affixed to the access member <NUM> in like manner for retracting soft tissue as needed.

Referring now to <FIG>, an attachment device <NUM> for the surgical access system <NUM> can include a flexible wire <NUM> that is configured to be inserted into the working channel <NUM> of the access member <NUM> in a first or insertion configuration and then deform into a second or deployed configuration for pushing the retractor body <NUM> against the inner wall surface <NUM> and securing it thereto. For example, the wire <NUM> can be pre-formed into a neutral shape, such as one or more coils, for example, and can then be loaded into an introducer instrument <NUM> (also referred to herein as the introducer <NUM>) that maintains the wire <NUM> in the insertion configuration. The introducer <NUM>, or at least an end portion thereof, can be inserted within the working channel <NUM>, and the wire <NUM> can be deployed (i.e., expelled) from the introducer <NUM> and into the working channel <NUM>, wherein the wire <NUM> elastically deforms from its insertion configuration to the deployed configuration. This deformation can cause the wire <NUM> to form one or more coils that extend circumferentially about the inner wall surface <NUM> and exert a radially outward spring force F that pushes the retractor body <NUM> securely against the inner wall surface <NUM> as the wire <NUM> attempts to return to its neutral configuration. In other embodiments, the wire <NUM> can be configured as a helical spring when in the neutral configuration, and can be further twisted helically so as to reduce its spring diameter when in the insertion configuration. Once inserted to the desired location within the working channel <NUM>, the wire <NUM> can be released so as to expand within the working channel <NUM> to the deployed configuration. It should be appreciated that the wire <NUM> can be constructed of a shape-memory material that is also bio-compatible, such as nitinol, by way of a non-limiting example.

The wire <NUM> can have a substantially purely coiled shape in the deployed configuration. In other embodiments, as shown in <FIG>, the wire <NUM> can have an alternate shape in the deployed configuration. For example, the wire <NUM> can be configured such that when it is in the deployed configuration, the wire <NUM> can define a longitudinal portion <NUM> configured to engage along the length of the retractor body <NUM> and one or more arm portions <NUM> configured to engage the inner wall surface <NUM> of the access member <NUM>. It should be appreciated that other deployed configurations are also within the scope of the present disclosure.

The retractor bodies <NUM> of any of the preceding embodiments can be constructed of bio-compatible materials including metals, polymers, composite materials, or any combination of the foregoing, by way of non-limiting examples.

It should be appreciated that the retractors <NUM> and attachment devices <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> described above allow selective placement of the retractor <NUM> relative to the access member <NUM>, including circumferentially and longitudinally, and thus likewise relative to patient anatomy for fine control of soft tissue retraction. Such fine control of soft tissue retraction is particularly beneficial because, among other things, it reduces the need for resection (removal) of soft tissue at the treatment site.

Referring now to <FIG>, the retractor members <NUM> of any of the embodiments described above can include at least one sensor <NUM> that is electrically conductive and located at or adjacent the distal end <NUM> of the retractor <NUM>. The sensor <NUM> can be employed for neuromonitoring (e.g., for detecting the presence, proximity, health, and/or other attributes of nerve tissue) at the treatment site, such as to navigate the retractor <NUM> around (e.g., avoid) nerve tissue, to safely retract nerve tissue with the retractor <NUM>, and/or to assess the health of nerve tissue at the treatment site, as more fully described in the '<NUM> Reference. It should be appreciated that the sensor <NUM> can include a single sensor or a plurality of sensors. The sensor <NUM> can be in electrical communication with an electric lead <NUM> that is located at or adjacent the proximal end <NUM> of the retractor <NUM> and is configured for transmitting electrical information obtained by the sensor to a control unit <NUM>, which can employ a processor <NUM> for interpreting the electrical information.

As shown in <FIG>, in one such embodiment that employs a sensor <NUM>, the retractor <NUM> can include a retractor body <NUM> that is constructed of an electrically conductive material. The retractor <NUM> can also include an electrically insulative sheath <NUM> disposed over a major portion 3i of the retractor body <NUM>. The sheath <NUM> can be configured to provide an exposed portion 3j of the retractor body <NUM> that defines the sensor <NUM>. The exposed portion 3j can extend from the sheath <NUM> to the distal end <NUM>. The sheath <NUM> can also be configured to provide another exposed portion <NUM> of the retractor body <NUM> that defines the electric lead <NUM>, which can extend from the sheath <NUM> to the proximal end <NUM>. It should be appreciated that, as an alternative to the sheath <NUM>, the retractor body <NUM> can be coated with a layer of insulative material, which layer can be formed or finished so as to provide an exposed portion of the retractor body <NUM> at or adjacent the distal end <NUM>, which exposed portion can define or carry the sensor <NUM>. The coating can also be configured to provide an additional exposed portion of the retractor body <NUM>, such as at or adjacent the proximal end <NUM>, for providing the electric lead <NUM>.

As shown in <FIG>, in another embodiment that employs a sensor <NUM>, retractor <NUM> can include a retractor body <NUM> that is constructed of an electrically insulative material, and the sensor <NUM> can be disposed over or embedded within the retractor body <NUM> at or adjacent the distal end <NUM> thereof. The electric lead <NUM> can also be disposed over or embedded within the retractor body <NUM>, such as at the proximal end <NUM> thereof. The retractor <NUM> can include an electrical transmission element, such as a wire or trace extending along or through the retractor body <NUM>, from the sensor <NUM> to the electric lead <NUM>.

The insulate materials described above can include parylene, silicone rubbers, fluoropolymers, and elastomers, by way of non-limiting examples. It should be appreciated that in other embodiments employing a sensor <NUM>, the sensor <NUM> can be in wireless communication with the control unit <NUM> and/or processor <NUM>.

Referring now to <FIG>, in yet other embodiments, an attachment device <NUM> for the surgical access system <NUM> can include a tether <NUM> extending from the proximal end <NUM> of the retractor body <NUM>. As shown in <FIG>, the retractor body <NUM> can be carried by an instrument <NUM>, which can include a distal elongate portion <NUM> that extends along the longitudinal direction L and carries the retractor body <NUM>, such as by bracketing the lateral sides of the retractor body <NUM>. The distal elongate portion <NUM> is configured for insertion within the access member <NUM> to engaging soft tissue with the retractor body <NUM>. The retractor body <NUM> can define a distal mount <NUM>, such as a hook, which can extend from the outer surface <NUM> of the retractor body <NUM>. Additionally, the distal mount <NUM> can be configured to engage the distal end <NUM> of the access member <NUM>. Additionally or alternatively, the distal mount <NUM> can be configured to selectively engage any of a plurality of slots <NUM> defined in the wall <NUM> of the access member <NUM>, as shown in <FIG>.

Claim 1:
A retractor member (<NUM>) configured for insertion through a channel (<NUM>) of an access member (<NUM>) and for moving soft tissue at a treatment site accessible through the channel, comprising:
a body (<NUM>) having a proximal end (<NUM>) and a distal end (<NUM>) spaced from each other along a longitudinal direction, the distal end defining a retractor blade, the body defining a first surface (<NUM>) and a second surface (<NUM>) opposite each other along a transverse direction substantially perpendicular to the longitudinal direction, wherein the body has a first side (<NUM>) and a second side (<NUM>) spaced from each other along a lateral direction substantially perpendicular to the longitudinal and transverse directions; and
an attachment device (<NUM>) configured to selectively attach the body to a portion of the access member such that the body is extendable through the channel and is translatable relative to the access member along the longitudinal direction while the body is attached to the portion of the access member, wherein the attachment device extends from at least one of the first and second sides at a longitudinal portion of the body located intermediate the proximal and distal ends, such that the attachment device is configured to reside within the channel for securing the retractor member to an inner surface (<NUM>) of the access member;
characterized in that the attachment device comprises a pair of wings (<NUM>) each extending circumferentially from the first and second sides, respectively, at the longitudinal portion, wherein the pair of wings are compliant and are configured to be flexed inward toward each other from a neutral configuration to a flexed configuration by the inner surface of the access member when the pair of wings are disposed in the channel, such that a return force of the pair of wings causes the pair of wings to engage the inner surface of the access member so as to attach the body to the portion of the access member.