Patent ID: 12256917

DETAILED DESCRIPTION

Tools for accessing the spine using an anterior to psoas approach may include any number of retraction instruments and/or blades. For example, access to the spine2may be provided through a system that includes a retraction instrument10and blade160as shown inFIG.1, where each structure is capable of reaching a surface of the spine and retracting tissue and other anatomy to create a surgical access portal so that a surgical site is accessible. Although each embodiment described herein makes reference to an anterior to psoas surgical approach, it is contemplated that the tools described herein may also be used in any number of other surgical procedures for the creation of access to a surgical site of a patient. For example, an anterior lumbar interbody fusion procedure (ALIF), or as known more generally as an anterior procedure, may also be used. We now turn to the details of the various tools used to create access to a surgical site.

Retraction instrument10is shown in more detail inFIG.2. Retraction instrument10includes a body12having arms20,24extending in parallel therefrom on one end and an attachment mechanism14on another end. The attachment mechanism14, one example of which is a universal quick release adapter, allows for engagement of body12with a handle19, as shown inFIG.1, or a rigid arm (not shown). One example of the attachment mechanism is the XIA 3 Quick Attachment by Stryker® and one example of the handle is the XIA 3 Quick Connect Handle by Stryker®. The rigid arm, if used, may be the same structure used in a lateral trans-psoas procedure. Each arm20,24is rigidly connected to body12and includes an engagement feature22,26, respectively, at an end opposite its attachment to body12. Rods30,34are attached to the respective engagement features22,26on the arms. The rods may be made of titanium or stainless steel, for example.

A more detailed view of one of the arms and rods is shown inFIG.3. Rod30is cylindrical in shape with a rounded distal end35and is orthogonal to arm20. In variants, the rod may be at another angle relative to the arm. It should also be noted that the rods are not limited to having a cylindrical shape, and that the rods may have another shape defined by a convex surface perimeter, or other shapes as described elsewhere in this application. A tapering structure31is attached on one side of each rod and faces the arm such that the tapering structure becomes larger toward the arm. Adjacent to a connection with arm20, rod30includes teeth32, spaced in a longitudinal direction and facing the arm. Within engagement feature22is a generally cylindrical threaded insert (not shown) that engages with teeth32to control a position of rod30relative to arm20along an axis through the arm in predetermined increments. The rods are removable from the arms by sliding the rod out of the engagement feature, and thus can be separated from an arm and reattached, as desired. In some alternatives, each of the engagement feature and the rod may include slots, dovetail connections, or other structures to facilitate attachment therebetween. Attachment of the rod to the arm may also be through other structural features described in U.S. Pat. App. Pub. No. 2019/0298328, the disclosure of which is hereby incorporated by reference herein in its entirety (“the '328 Publication”).

Retraction instrument10is advantageous in that it includes retraction structures in the form of rods with perimeters defined by convex surfaces, e.g., cylindrically shaped, and occupying a minimal cross-sectional area. The size and shape of the rods reduces the interference of the retraction instrument with the operative space, allowing a surgeon to approach the surgical site from many angles and positions. Additional operative space is also made available in view of the space between the arms from the main body to the rods. Further, the rounded surface of the rods reduces the risk of damaging internal organs of the patient during advancement of the instrument. Moreover, each rod is engineered to withstand a certain amount of deflection under loading. Put another way, the properties of the rods provide sufficient elastic flexibility to withstand deflection that can result from tissue bearing on the rods during use without reaching yield under the highest loads expected within a body of a patient. The rods as described are also usable in a retractor adapted for use in a lateral trans-psoas approach, such as the retractors described in the '328 Publication. Because the rods may be detached and reattached, it is envisioned that rods already attached to the retraction instrument may be detached and then reattached to a lateral trans-psoas retractor.

The retraction instrument may be varied in many ways. In one embodiment, a retraction instrument110is as shown inFIGS.6and7. Unless otherwise noted, like reference numerals refer to like elements as shown inFIGS.2and3. Instrument110includes a central body112with attachment mechanism114on a first side and a pivot structure113on an opposite side. As shown, a handle119is attached to attachment mechanism114, although the handle may be replaced so that the instrument is secured by a rigid arm (not shown). Attached to central body112in a fixed manner is rack114. As seen inFIGS.6and7, rack extends orthogonally from a length of central body112. In alternative variations, the rack may be oriented at another angle relative to the central body as a matter of design choice. Disposed over rack114is sleeve116. Sleeve116is sized for a secure fit over rack114. Rack114includes teeth115and sleeve includes corresponding teeth so that sleeve116is movable in predetermined increments along rack114. In an alternative configuration, an engagement feature other than teeth may be used.

FIGS.6and7also show arm120extending from pivot mechanism113of central body112and arm124extending from a pivot mechanism117on sleeve116. Arms120and124are parallel to one another and a distance between the arms may be between 12 mm and 15 mm, though the amount may vary as a matter of design choice. Because arm124is secured directly to sleeve116, movement of sleeve116relative to central body112along rack114correspondingly moves rod134relative to rod130, as shown inFIG.6. In this manner, retraction instrument110provides for an adjustable retracted surgical access portal. The pivot mechanisms113,117as shown provide fixed securement of the arms to the body and rack, respectively. Alternatively, the arms may be adjustable relative to the body such that the arms are locked in a desired position relative to the central body and rack. For example, an angle between a length of one or more arms relative to a plane passing through both the central body and rack may be adjusted by rotating the arm about the pivot mechanism.

Turning to the rods used with the retraction instrument, in one example, as shown inFIG.6, each rod130,134includes a cannulation therethrough. The cannulations through such rods are sized for the disposal of threaded pins138,139therein. As shown inFIG.6, the pins are engageable with vertebral bodies4,6when positioned in a patient. These rod variations may also be used with other embodiments of the retraction instrument described and otherwise contemplated elsewhere in the disclosure.

In one embodiment, a retraction instrument210, shown inFIGS.8and9, includes handles218,219attached to respective arms220,224. At an end of each arm220,224, a rod230,234, is attached. Unless otherwise noted, like reference numerals refer to like elements as shown inFIGS.2and3. Handles218,219are pivotable with respect to one another and are connected at a location on a pivot axis201. When handles218,219are brought closer together, as shown comparingFIG.8toFIG.9, distal ends of arms220,224and attached rods230,234move away from one another. Adjacent to an interface between arm224and handle219, arm224includes an attachment mechanism214for securement of retraction instrument210to a rigid arm. In a variation, the handle and arm combination may be arranged like scissors, so that each handle is connected to an arm on an opposite side. In this manner, closing of the handles brings the rods closer together while opening of the handles spreads the rods further apart.

In some examples of the retraction instrument, the attached rods may have an oblong, elliptical, ovular or any other cross-sectional shape as desired. In other examples, one or more of the rods may have a pointed tip shaped to engage bone upon loading thereon. Retraction instruments including such rods may be secured to a bone without a separate anchoring structure. Further examples of rod shapes and other rod details are provided in the '328 Publication, incorporated by reference above, and in WO2018/039228, the disclosure of which is hereby incorporated by reference herein in its entirety (“the '228 Publication”). In some examples, the body, arms and/or rods may be comprised of a monolithic structure in whole or in part. Thus, the body and arms may be a monolithic structure or an arm and a rod connected to the arm may be a monolithic structure. Further, the body, arms and rods may all be a single monolithic structure. In other examples, various combinations of the body, arms and rods may be integral. In further examples, a length of a body of a retraction instrument may be at an angle relative to a length of one or more arms attached thereto. Similarly, where the retraction instrument includes a rack, the rack may be at any angle relative to the central body and/or one or more of the arms. The angle between elements in these examples may be such that all structures are in a single plane or one or more structures may be angled out of plane with respect to the others. For example, a retraction instrument may include two arms passing through a single plane while the main body and handle extend at an angle from the arms out of the single plane. Similar variations are contemplated for an angle between the rods and the arms. And, a length of a first arm may be at an angle relative to a length of a second arm.

In other examples, a first rod on a retraction instrument may be different from a second rod. Any combination of the rods described in the '328 Publication and the '228 Publication may be included. In still further examples, the retraction instrument may include three or more rods with corresponding arms. The rod and arm combinations may be parallel with one another or one or more may be at an angle relative to the others. In yet another example, the rods may be attached to a single body without any arms.

In another aspect, the present disclosure relates to a pin holder40as shown inFIGS.4and5. Pin holder40includes a cylindrical component45and a partially cylindrical component46that is monolithic with the cylindrical component. However, in an alternative configuration, the partially cylindrical component may be a separate structure attached to the cylindrical component. The cylindrical component includes an internal channel therethrough sized for the disposal of a bone pin. InFIG.5, bone pin50is disposed within cylindrical component45of pin holder40. Partially cylindrical component46includes a groove47therethrough to define a c-clip structure. As shown inFIG.4, groove47is sized to accommodate rod30of retraction instrument10therein. Groove47is parallel to the internal channel of the cylindrical component such that when pin holder46is attached to a rod, for example, bone pin50disposed within pin holder40is parallel to the rod. The c-clip of partially cylindrical component46provides a friction fit to an element engaged thereto.

The pin holder is advantageous in that it adds a bone securement feature to retraction instrument10,110,210and it is insertable after a portal is created to avoid having to pass a pointed tip on the bone pin of the pin holder through anatomy of the patient. Further, the position of the internal channel offset from the c-clip structure allows a surgeon to screw in a bone pin while the pin holder is engaged to a rod.

In another aspect, the present disclosure relates to blades. One embodiment of a blade is a double pin blade60shown inFIGS.10and11. Double pin blade60includes a proximal portion61, central portion62and a tapered distal portion63. Proximal portion61extends at an angle relative to central portion62and includes an opening (not shown) for engagement to a handle or a rigid arm via an attachment mechanism.

Turning to central portion62, central portion62has a linear length with a concave surface71on one side and a convex surface81on an opposite side. On opposite lateral sides of concave surface71are longitudinally extending first and second lateral grooves72,74, respectively, as best shown inFIG.10. Lateral grooves72,74are nearly enclosed in their entirety, although in variants, a forward facing opening in the grooves may be wider or narrower than shown inFIG.10. Each lateral groove is sized for the disposal of a bone pin90A,90B therein. Coincident with a central longitudinal axis of double pin blade60on central portion62is a central recess including an upper central recess76A,76B and a lower central recess77that is recessed relative to the upper central recess76A. Through central portion62of double pin blade60, upper central recess76A is wider than lower central recess77, each having a generally constant width along the central portion. Within the recesses, the surface of the blade is relatively flat compared to the convex curvature between the upper central recess and opposing lateral grooves. The various recesses in the blade are sized to accommodate disposal of a light emitting structure therein.

Tapered distal portion63extends from central portion62to a rounded tip64of the blade. As shown inFIG.10, lower central recess77terminates near a distal end of central portion62and only upper central recess76B extends toward tip64. Upper central recess76B is slightly narrower than upper central recess76A. As shown inFIG.11, as blade60tapers toward tip64, it curves away from a plane through the first and second lateral grooves72,74. This curvature is indicated by reference numeral65inFIG.11. It should also be noted that the surface on distal portion63extending from concave surface71on central portion62is also concave.

Opposite concave surface71is convex surface81, as shown inFIG.11. Convex surface81is interrupted on a central axis by a longitudinally extending central ridge82corresponding to upper and lower central recesses76A,76B,77. Since concave surface71and convex surface81are opposing surfaces on blade60, a cross-section through double pin blade60is defined by a generally arcuate shape.

In another embodiment, a system includes double pin blade60and pins90A,90B. Pin90A includes a cylindrical body extending from a head91A to a tip92A. A majority of a length of pin90A includes a smooth surface, although a distal end portion94A extending to tip92A is threaded. Pin90B is the same as pin90A. In the system, each pin90A,90B is disposed in respective first and second lateral grooves72,74, as shown inFIGS.10and11. In a variant, a system may include a single pin along with a double pin blade.

Double pin blade60is advantageous in that it is adapted to house up to two pins for securement of blade60to a bone structure. Indeed, when two pins are used to secure blade60to a bone structure, both rotational and axial securement are realized. Further, blade60includes a contoured tip64to improve surface area contact with curved surfaces, such as those on the spine.

In another embodiment, blade160is as shown inFIGS.12and13. Unless otherwise noted, like reference numerals refer to like elements as shown inFIGS.10and11. Blade160includes a proximal portion161, a central portion162and a tapered distal portion163. Proximal portion161is angled relative to central portion and includes an opening for engagement with an attachment mechanism196. As shown inFIG.12, the attachment mechanism196is connected to handle198, although in other variants, attachment mechanism may be connected to a rigid arm. As shown inFIG.13, central portion162includes a concave surface with two lateral portions172,174separated by a recessed portion176. A surface opposite the concave surface is convex (not shown). Distal to central portion162and extending to a tip164of blade160is tapered portion163. Tapered portion is curved so that a surface on the tapered portion retreats in a direction away from a plane through respective lateral edges of blade160toward tip164, as shown inFIG.12. An extreme end of tip164is rounded. In a variant, a light emitting structure185may be secured onto recessed portion176with adhesive backed tape, for example, as shown inFIG.1. Other forms of securement are also contemplated, which may be chosen as a matter of design choice. This light emitting structure provides light directed to the distal tip of blade160.

In yet another embodiment, a double pin blade260is as shown inFIGS.14-16. Unless otherwise noted, like reference numerals refer to like elements as shown inFIGS.10and11. Double pin blade260includes a central portion262with a convex surface271. Similar to double pin blade60, concave surface271includes first and second lateral grooves272,274and centrally located upper and lower central recesses276A,276B,277. A plane269passes through both lateral grooves272,274. Distal portion263of blade260is not tapered but does curve away from plane269. In particular, for example, lateral edges265,266, as shown inFIGS.14and16, become further from plane269toward distal end264. A surface between lateral edges265,266is concave on the same side of blade260as concave surface271. Also visible inFIG.16, distal end264has a rounded edge.

In yet another embodiment, the present disclosure relates to a composite blade360that includes an outer blade component370and an inner blade component380. Inner blade component380is narrower than outer blade component and is engageable with a groove375in outer blade component370, as shown inFIG.17. In one example, outer blade component is 25 mm wide while inner blade component is 5 mm wide. Inner blade component is at least partially linear382and is engageable with outer blade component370. For example, a surgeon may clip inner blade component380onto outer blade component370. A distal end portion383of inner blade component380is angled and has surface contours to suit contact with a curved surface, such as a vertebral body or intervertebral disc. Once attached to outer blade component370, inner blade component380may be removed and reattached as desired. It should be appreciated that an inner blade component such as inner blade component380, may also be sized for receipt in other blades of the disclosure, including, for example, double pin blade60.

Another embodiment of the composite blade is shown inFIGS.24and25. Unless otherwise noted, like reference numerals refer to like elements as shown inFIG.17. Composite blade760includes an outer blade component770and a light bar785which is engageable with a groove775in outer blade component770. Engagement of the elements is through a snap fit connection so that light bar785may slide within groove775, though the form of engagement may vary as a matter of design choice. Composite blade also includes inner blade component780, which may be independently operated with respect to outer blade770, though it is sized to fit along groove775to guide a position of a curved distal portion783. Inner blade component780also includes a bent segment784toward a proximal end78. Curved distal portion783and bent segment784are separated by a linear central portion782. Curved distal portion783and bone segment784both extend in the same direction away from a plate through central portion782, as shown inFIG.25.

The blade may be varied in many ways. Additional examples of blades, along with another view of blades60and260, are illustrated inFIG.18. Blade460includes a linear taper464sloped away from a plane through the lateral edges of the blade. Blade560includes a tapered portion564that is sloped toward a plane through the lateral edges. Blade660is a smaller blade having a curved distal portion. It is also contemplated that the blade may be varied to suit particular surgical needs. For example, the radius of the surface across the width of the blade may be greater or less than that shown in the figures. In other examples, the length or width of the blade may vary to suit particular circumstances.

In another aspect, the present disclosure relates to a kit. A kit may be contained in a single package as a system or in multiple packages that may be selected as needed by a surgeon to form a system. In one embodiment, a kit includes a retraction instrument and a blade. When referred to as part of a kit, a blade may be any blade described or otherwise contemplated in this disclosure. In another embodiment, a kit includes a retraction instrument and two or more blades. Any combination of blades may be included, either multiple blades of the same type, or different blade types. In yet another embodiment, a kit includes two or more retraction instruments and a single blade. When two or more retraction instruments are included, each instrument may be the same or may be different. In further embodiments, a kit may include two or more retraction instruments without any blades or may include two or more blades without any retraction instruments. In each of the above embodiments, the kit may also include multiple units of a single type of blade but in different sizes. It is also contemplated that the above kits may be further modified to include other surgical tools used in conjunction with the retraction instrument and blades. In some examples of the above embodiments, the kits contemplated herein may be accompanied by an instruction manual on how to perform one or more of the methods of using the contents of the kit.

In yet another embodiment of the kit, tools of the described anterior to psoas system are included as part of a larger kit including a lateral trans-psoas system, such as the system and subcomponents described in the '328 Publication. In some examples, such a kit includes a lateral trans-psoas retractor system, an anterior to psoas retraction instrument with two arms and two rods and a composite blade. In other examples, it includes a lateral trans-psoas retractor system and any combination of anterior to psoas tools as described in the other kit embodiments above. The lateral trans-psoas retractor system forming part of the kit may include any number of components and tools described in the '328 Publication.

In another aspect, the present disclosure relates to a method of accessing the spine using an anterior to psoas approach. As noted above, although the specific embodiments described herein are directed to procedures employing an anterior to psoas approach, other procedures, such as an ALIF procedure, are also contemplated. Prior to commencement of the surgical technique using the tools of the present disclosure, preparation of the patient is required. These preliminary steps include but are not necessarily limited to: Positioning the patient; identifying an incision location based on the targeted spinal location; and cutting through muscle layers to create an opening for accessing spine. In an anterior to psoas approach, external oblique, internal oblique, transversus abdominus and transversalis fascia tissues are penetrated to create an initial opening, or initial portal, so that the surgeon may identify the psoas muscle and/or other anatomy and use such anatomy to locate the spine. In certain examples, the techniques described herein may be used to access vertebrae at L3/L4, L4/L5 and L5/S1.

In one embodiment, with an initial portal3opened that is large enough so that tools may be advanced into the patient, as shown inFIG.19, an outer blade component370of a composite blade360is advanced into the patient using an anterior approach to the spine on one side of the initial portal3. During advancement of blade component370, certain anatomy may be retracted medially including the peritoneum. Once outer blade component370is advanced close to the spine, inner blade component380is clipped onto groove375on outer blade component370and blade component380is slid down the groove so that a distal portion383is advanced beyond end373of outer blade component370until it is in contact with the spine and it otherwise retracts or protects the vessels from the spine, as shown inFIG.20. The contours of the distal portion383of inner blade component380are then used to identify a position where contact between distal portion383and the intervertebral disc is maximized. In this manner, composite blade360is stabilized on the disc. At this time, a position of blade360may be preserved by manually holding a handle, or blade360may be secured to a fixed structure using a rigid arm (not shown).

With blade360in position, rods30,34of retraction instrument10are directed to an opposite side of the partially retracted opening from blade360, as shown inFIG.21, and then advanced into the patient using an antero-lateral approach. Because rods30,34have rounded outer surfaces, the risk of damaging internal organs during the advancement of the rods is minimized. Once rods30,34are in position adjacent to the spine, as shown inFIG.21, retraction instrument10is either held in place or secured with a rigid arm19A. The advancement of the rods retracts anatomy behind the rods, including psoas muscle8among other anatomical structures, creating a surgical access portal9, shown inFIG.21, for use by the surgeon to prepare a target intervertebral disc, place an implant or perform another task requiring access to the spine. In position, the respective rods30,34are positioned directly over adjacent vertebral bodies4,6, as shown inFIG.22. In some examples, either one or both of blade360and retraction instrument10may be further retracted at this time to increase the size of the surgical access portal or otherwise adjust its shape.FIG.22illustrates the position of the retraction instrument and blade at this stage of the procedure. Once the rods and blades are in position, the intervertebral disc5is accessible for the applicable surgical procedure.

Because rods30,34of retraction instrument10retract tissue but are also spaced apart, and because arms20,24are spaced apart, retraction instrument10provides a unique advantage in that a surgeon has more space to operate once surgical access portal9is created. For example, if the surgeon attaches an implant onto an insertion instrument, the surgeon may direct the instrument in between the rods or at steeper angles relative to the surgical access portal than would otherwise be possible with a traditional blade. Similar advantages are available for the insertion of disc preparation instruments.

Optionally, additional blades760, shown in phantom inFIG.22, may also be advanced into the surgical access portal and retracted to further increase the size of the surgical access portal or to adjust its shape.

In some variations of the method added stability, i.e., rigidity, is provided by attaching a pin holder40to one of the rods, such as the pin holder shown inFIG.5, and sliding it down the rod so that a bone pin50disposed within the pin holder is in contact with or otherwise adjacent to a surface of a vertebral body. It should be noted that as pin holder40is advanced, the c-clip provides a friction fit with the rod so that the pin holder may be positioned at any desired location along the length of the rod and remain in that position. The sliding step may be performed by attaching a longitudinally extending driver instrument (shown in part as reference numeral58onFIG.4) to the pin holder and then using a handle on the driver instrument to push down the pin holder. Driver instrument58includes an end opening shaped to mate and fit securely with head52of the bone pin so that the bone pin may be advanced. Because drive instrument58has an extended handle, the surgeon may continue to hold the driver instrument at a location external to the patient even when pin holder40is advanced toward a vertebra. One example of the driver instrument is the driver included as part of the ARIA System by Stryker®. To secure the bone pin to a bone beneath it, head52of bone pin50is actuated to drive a threaded portion55of the bone pin into the bone. As the bone pin is rotated and advanced, the pin holder remains attached to the rod. Because the rod of the retraction instrument is attached to the pin holder, once the bone pin is secured to the bone, the retraction instrument is also secured to the bone. This bone anchoring step may also be performed on the other of the two rods so that both rods30,34are secured to bone. When both rods are secured with bone pins, both rotational and axial securement of the retraction instrument are realized. Additionally, for subsequent surgeries, the bone pin in the pin holder may be replaced.

In another embodiment, the steps of the surgical technique are the same as those used to create the surgical access portal defined by the instrument and blade shown inFIG.22, although retraction instrument110is used in place of retraction instrument10. In this variation, once the rods of retraction instrument110are in position over the bone, sleeve116is adjusted to control a distance between the rods. This may be done to ensure that each rod is over the proper location on a vertebral body, for positioning of the rod so that an attached bone pin in a pin holder will properly engage the vertebral body, or for modification of the size or position of the surgical access portal. In yet another embodiment, similar principles apply to use of retraction instrument210to adjust positions of rods230,234with respect to each other.

In yet another embodiment, a surgical technique involves the same steps as described above up to and including advancement and positioning of composite blade360, although once composite blade360is in position over a vertebral body within the patient, two double pin blades60are used to complete the requisite retraction to create the surgical access portal, instead of the retraction instrument. Here, each double pin blade60is inserted into the surgical access portal using an antero-lateral approach so that respective blades60are positioned over a vertebral body, as shown inFIG.23. The positioning of each blade60is performed so that the three blades are approximately equidistant from one another, again, shown inFIG.23. However, the position of each tool in the body may vary depending on the surgery. In some examples, curved tip64of blade60is used to guide the blade over a curved vertebral surface4,6and provide increased surface contact between the blade and the vertebral surface.

Once double pin blades60are in position, they may be manually held in place for the surgical procedure or they may be externally fixed using a rigid arm (not shown). Optionally, one or two bone pins90A,90B may be disposed within grooves on blade60and advanced into a vertebral body below the blade60to provide additional support for the surgical access portal. This may be done for one or both blades. In the embodiment shown inFIG.23, the bone pins90A,90B are longer than the blade so the bone pins may be actuated from above the blade while also penetrating a vertebral body below the blade. When the pin(s) is secured to the vertebral body, the blade(s) is rigidly attached to the vertebral body for the remainder of the surgical procedure. This approach is advantageous as it provides the option for additional rigidity in the blade in addition to the rigidity provided by a rigid arm. Further, the option of securing a single blade to a bone with two pins provides rotational stability along with axial stability.

Additionally, in other examples of the surgical technique, a light emitting structure, such as a fiber optic light bar (not shown), may be clipped onto upper and lower central recess76A,77of double pin blade60and slid down to a desired location on the blade to direct light into the surgical access portal. The blade may further include a preset stop with a highly reflective surface. In this manner, once a distal end of the light bar is positioned at the preset stop, light may be directed into a working area of the surgical portal. Similarly, a light bar or light pipe may be inserted through a cannulation in the rod and advanced to a preset stop at an end of the cannulation on a side of the rod, the preset stop directing light into the portal. The light emitting structure may also be clipped to blade260in the same manner. Other lighting technologies contemplated for inclusion on the rods of the retraction instrument and the blades of the present disclosure include those described in WO2019/036048, the disclosure of which is hereby incorporated by reference herein in its entirety.

In yet another embodiment, the surgical method employs composite blade760, shown inFIGS.24and25, in place of composite blade360. In this method, outer blade component770is initially advanced into the patient. Blade770may be advanced with or without a light transmitting structure785disposed therein. In some examples, the light emitting structure may be slid onto blade770after the blade is in position. Once blade770is in position over vertebrae2, inner blade structure780is advanced at a desired angle, such as that shown inFIG.25, or at a varying angle, toward a target site in the patient. When curved distal portion783is near distal end773of outer blade component770, it is carefully advanced over the distal end and rotated outward away from blade770to push anatomy on the concave side of curved distal portion783backward to improve access around the target site. Adjustments to a position of blade component780may be made as desired and once a final position is decided upon, inner blade component780is secured in position using a separate securement mechanism from that used to secure outer blade component770.

The surgical method may be varied in many ways. Various combinations of the blades disclosed herein, including blades60,160,260,360,460,560,660and760may be used to create a surgical access portal to access the spine. Any number of these blades may be used in combination with any retraction instrument10,110,210. When blades160,260,460,560,660,760are used to create a surgical portal, the curved distal end of the applicable blade may also mate with an intervertebral disc or vertebral body to obtain increased surface area contact between the blade and the vertebral surface. Additionally, the rods for each of the retraction instruments may be removed and used interchangeably with lateral trans-psoas retractor systems, such as those described in the '228 Publication.

Although the disclosure herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present disclosure. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present disclosure as defined by the appended claims.