Patent Application
20160345952
Field of the Disclosure
The present application relates to devices, systems and methods for treating the spine. In certain embodiments, the present application relates to devices, systems and methods for providing spinal stabilization, such as a spinal fusion. In particular, certain embodiments relate to minimally invasive devices and methods for delivering fixation devices and implants into the spine.
Description of the Related Art
Spinal bone and disc degeneration can occur due to trauma, disease or aging. Such degeneration can cause abnormal positioning and motion of the vertebrae, which can subject nerves that pass between vertebral bodies to pressure, thereby causing pain and possible nerve damage to a patient. In order to alleviate the pain caused by bone degeneration, it is often helpful to maintain the natural spacing between vertebrae to reduce the pressure applied to nerves that pass between vertebral bodies.
To maintain the natural spacing between vertebrae, spinal stabilization devices are often provided to promote spinal stability. These spinal stabilization devices can include fixation devices, such as spinal screws, which are implanted into vertebral bone. The fixation devices work in conjunction with other implanted members, such as rod members, to form stabilization systems.
Spinal stabilization devices are often used in conjunction with spinal fusion techniques, which can increase stability of the spacing between vertebrae by fusing adjacent vertebrae together. Two of the most common spinal fusion techniques are the transforaminal lumbar interbody fusion (TLIF) and the posterior lumbar interbody fusion (PLIF).
Conventional stabilization systems and techniques often require open surgeries and other invasive procedures in order to deliver the implants into the body. These invasive procedures often cause a great deal of pain and trauma to the patient, and require a substantial recovery time. Minimally invasive (MIS) and maximal access (MAS) systems and methods exist, but they are relatively new and with room for improvement.
Various embodiments described herein relate to a minimally invasive retractor access system that can be used as part of a minimally disruptive muscle sparing approach to the spine. Embodiments described herein can be used for single and multi-level spinal fusions. Embodiments described herein can also be used for bilateral distraction of a spinal disc space during a spinal procedure, such as by distracting from devices attached to bone screws on both sides of a spine. Among other benefits, this can help when distracting tight disc spaces.
In some embodiments, a minimally invasive surgical system for treating the spine can include at least one blade assembly. The blade assembly can have a blade with a central section having a central bore and wings extending outward from the central section on opposite sides thereof. The wings also extend to a location below a bottom of the central section, forming a gap bounded by the wings on two sides and the bottom of the central section on a third side. The blade assembly can also have a post extending from an upper surface of the blade and a shaft positioned at least partially within the central bore of the blade, the shaft having an externally threaded lower section and a central shaft bore that runs through the length of the shaft. The shaft can be rotatable within the central bore of the blade.
In some embodiments, the blade assembly can include an attachment section extending from the blade. In some embodiments, the shaft can have a plurality of vertical grooves extending around at least a portion of the shaft. In some embodiments, the blade assembly can further include a locking pin positioned within the attachment section, the locking pin moveable between a locked position in which a point on one end of the locking pin engages at least one of the vertical grooves of the blade shaft, substantially preventing rotation of the shaft, and an unlocked position in which the point is disengaged from the vertical grooves. In some embodiments, the locking pin can also be biased toward the locked position. In some embodiments, the vertical grooves are angled relative to a diameter of the shaft bore such that the locking pin in the locked position only prevents rotation of the shaft in one direction.
In some embodiments, the externally threaded lower section extends at least partially into the gap. In some embodiments, the surgical system can further include a pedicle screw having a screw shank and a housing attached to an upper end of the screw shank. The housing can have internal threading configured to receive the external threads of the lower section of the blade shaft.
In some embodiments, the surgical system can further include a retractor having a cross bar with a plurality of arms extending from the cross bar. In some embodiments, at least one of the arms can move relative to the cross bar to thereby change a distance between the arms. In some embodiments, each arm at its end farthest from the cross bar can have a collar configured to attach to the post of the blade assembly. In some embodiments, an attachment assembly can be connected to one of the arms, the attachment assembly configured to attach to a minimally invasive tower access device.
In some embodiments, the retractor can have a first set of arms extending from the cross bar on a first side of the cross bar, and a second set of arms extending from the cross bar on a second side of the cross bar. Each arm of the first set can have at least one articulating section. The arms of the first set can be moved closer together or further apart and the arms of the second set can be moved closer together or further apart. In some embodiments, each arm of the second set can be configured to attach to a minimally invasive tower access device. In some embodiments, when the arms of the first set are attached to blade assemblies that are attached to pedicle screws positioned within pedicles on the first side of a pair of adjacent vertebrae, and when the arms of the second set are attached to minimally invasive tower access devices that are attached to pedicle screws positioned within pedicles on the second side of the pair of adjacent vertebrae, the arms of each set can be simultaneously moved further apart to distract the disc space between the pair of adjacent vertebrae.
In some embodiments, a medial blade assembly can be configured to attach to at least one of the arms, the medial blade assembly comprising a medial blade configured to be movable toward the cross bar. In some embodiments, the medial blade assembly is movable in a direction toward at least one of the arms.
In some embodiments, a minimally invasive surgical system for treating the spine includes a plurality of pedicle screws for insertion into the pedicles of adjacent vertebrae, with each of the pedicle screws having an upper portion that is internally threaded. The system can also include a plurality of retractor blades, each of the blades having an externally threaded lower section configured to engage the internally threaded upper portion of a corresponding pedicle screw. The system can further include a plurality of retractor arms configured to move the retractor blades closer together or farther apart. In some embodiments, the system can further include a plurality of minimally invasive tower access devices configured to engage at least some of the plurality of pedicle screws. In some embodiments, the plurality of retractor arms includes at least some retractor arms configured to engage the plurality of minimally invasive tower access devices to move the minimally invasive tower access devices closer together or farther apart. In some embodiments, the system can further include an implant configured to be delivered between the plurality of retractor blades or between the plurality of tower access devices.
In various embodiments, a minimally invasive surgical system for treating the spine can include multiple pedicle screws, each pedicle screw configured to be positioned in a respective pedicle of at least a first vertebra and a second vertebra adjacent the first vertebrae. The system can also include multiple pedicle screw extensions, each extension configured to engage a respective pedicle screw. The system can further include a retractor body having a cross bar, a plurality of arms extending from the cross bar with at least two of the arms movable relative to each other, and four connection assemblies, each connection assembly attached to an arm and configured to attach to a respective pedicle screw extension and pedicle screw. In some embodiments, moving the at least two arms apart from each other moves the connection assemblies attached to pedicle screws positioned in the pedicles of the first vertebra apart from the connection assemblies attached to pedicle screws positioned in the pedicles of the second vertebra.
In some embodiments, a retractor system can be sized and configured to enable a multi-level surgery. For example, some embodiments can include six screws and connectors. Accordingly, in some embodiments you can distract between the first two pairs of screws (e.g., a left pair and the middle pair). Once the interbody is placed, the retractor can be moved to the second two pairs of screws (e.g., the middle pair and right pair) in order to distract the next level. In some embodiments, the retractor is long enough to distract directly between the left pair and the right pair.
In some embodiments, the retractor body can include two arms and each arm can be attached to at least one connection assembly. In some embodiments, at least one of the pedicle screw extensions can be or attach to blade assemblies and at least one of the pedicle screw extensions can be or attach to tower access devices. In some embodiments, the plurality of arms can extend from the cross bar on the same side of the cross bar.
In various embodiments, a screwdriver and screw extender can be used to help attach screws used in spinal procedures. The screwdriver can have a section with ridges, and the screw extender can have a moveable locking plate with an edge or tooth configured to releasably engage the ridged section of the screwdriver. In some embodiments, the locking plate can be biased into engagement with the screwdriver. In some embodiments, a user can manually release the locking plate from engagement with the screwdriver. In some embodiments, a screw extender can have multiple locking plates or other components configured to releasably engage the screwdriver.
In some embodiments, a minimally invasive surgical system for treating the spine comprises at least one anchor extension attachment assembly. The anchor extension assembly comprises a tube having a central section with a central bore. An arm attachment portion is coupled to the tube and configured to be coupled to a retractor arm. First and second flange portions are coupled to a spring-loaded hinge portion that is coupled to the tube, the second flange portion has a hook portion configured to releasably engage a portion of the retractor arm.
In some embodiments, a minimally invasive surgical system for treating the spine comprises at least one medial blade assembly. The medial blade assembly comprises an assembly attachment portion configured to be coupled with a retractor arm. A medial blade positioning portion is configured to be adjustably coupled to the assembly attachment portion. A medial blade arm is configured to be adjustably coupled to the medial blade positioning portion and configured to be coupled to a medial blade.
In some embodiments, a minimally invasive surgical system for treating the spine comprises at least one medial blade. The medial blade comprises a blade body having a proximal portion and a distal portion wherein the proximal portion is thicker than the distal portion. A slot is defined along a length of the blade body and configured to receive a lighting element tool. A proximal portion of the blade body comprises an opening and is configured to receive a top-loading self-retaining attachment feature to secure the blade to a top surface of a retractor tool support portion of a surgical retractor system.
In some embodiments, a minimally invasive surgical system for treating the spine comprises at least one spacing tool. The spacing tool comprises first and second handle portions. A ratchet mechanism is coupled to the first and second handle portions and configured to hold the tool in an expanded position in a first open configuration. A pivot portion is coupled to the first and second handle portions. First and second arms extend distally from the first and second handle portions. First and second spacer portions coupled to distal portions of the first and second arms have substantially hemi-spherical cross-sectional portions. The tool is configured to be actuated from a closed configuration to an open configuration and held in the open configuration by the ratchet mechanism to provide a working space at a surgical location.
In some embodiments, a minimally invasive surgical system for treating the spine comprises a plurality of anchor extension attachment assemblies. Each of the plurality of anchor extension attachment assemblies comprises a shaft having a central section with a central bore. An arm attachment portion is configured to be coupled to a retractor arm. A spring-loaded locking clip is coupled to the arm attachment portion and configured to releasably engage the retractor arm. The shaft is configured to be coupled to anchor extension assemblies comprising extended tab percutaneous screws.
Methods are also described herein. In some embodiments, a minimally invasive surgical method for treating the spine includes delivering a first pedicle screw into the pedicle of a first vertebra and a second pedicle screw into the pedicle of a second vertebra, the first and second pedicle screws having threaded upper portions. The method can also include distracting a disc space between the first and second vertebra by moving retractor blades engaged with the threaded upper portions of the first and second pedicle screws, and delivering an implant between the retractor blades into the disc space. In some embodiments, the method can further include delivering a third pedicle screw into the pedicle of the first vertebra on a contralateral side relative to the first pedicle screw, and delivering a fourth pedicle screw into the pedicle of the second vertebra on a contralateral side relative to the second pedicle screw. In some embodiments, the disc space further can be distracted at least in part by moving screw extensions engaged with at least two pedicle screws. In some embodiments, the screw extensions can be minimally invasive access towers. In some embodiments they can be retractor blades. In some embodiments the screw extensions can be integral to or attach to the housing of the pedicle screw. In some embodiments, the disc space can be distracted by simultaneously moving the retractor blades and screw extensions.
In another embodiment, a minimally invasive surgical method for treating the spine is provided. The method comprises delivering a first bone anchor into a first vertebra and a second bone anchor into a second vertebra, wherein the first bone anchor comprises a first shank and a first housing having a first extended tab and a first height, and wherein the second bone anchor comprises a second shank and a second housing having a second extended tab and a second height. A first portion of the first extended tab is removed such that the first housing has a third height less than the first height. A first portion of the second extended tab is removed such that the second housing has a fourth height less than the second height. A second portion of the first extended tab is removed after removing the first portion of the first extended tab, such that the first housing has a fifth height less than the third height. A second portion of the second extended tab is removed after removing the first portion of the second extended tab, such that the second housing has a sixth height less than the fourth height.
In some embodiments of the above method, removing a first portion of the first extended tab may comprise breaking the first portion off of the first extended tab. The third height may be equal to the fourth height. The fifth height may be equal to the sixth height. The method may further comprise positioning an attachment assembly over the first extended tab before removing the first portion of the first extended tab. The attachment assembly is a blade assembly. Removing the second portion of the first extended tab may comprise breaking the second portion off of the first extended tab. The method may further comprise inserting a surgical device into a working space before removing the second portion of the first extended tab and the second portion of the second extended tab, wherein at least a portion of the working space is between the first extended tab and the second extended tab. The surgical device may be an implant. The surgical device may be a tool. The first housing and/or the second housing may be monolithic.
In another embodiment, a minimally invasive surgical system for treating the spine is provided. The system comprises at least one bone anchor comprising a shank and a housing having an extended tab, the housing having a first height from a distal tip of the housing to a proximal tip of the housing, the extended tab comprising a plurality of frangible sections. The system also comprises an attachment assembly comprising an internal longitudinal bore sized to fit over at least a portion of the extended tab of the at least one bone anchor. The system also comprises a retractor assembly comprising a retractor arm configured to attach to the attachment assembly.
In some embodiments of the above system, the attachment assembly may have a second height from a distal tip of the attachment assembly to a proximal facing surface of the attachment assembly, the second height being less than the first height. The retractor arm may attach directly to the attachment assembly. The extended tab may comprise two prongs defining a transverse channel between them. The attachment assembly may comprise an inward projection configured to fit within at least a portion of the transverse channel. The system may further comprise a sleeve configured to be placed around a portion of the extended tab of at least one of the at least one bone anchors. The sleeve may be configured for placement between the extended tab of the at least one of the at least one bone anchors and an attachment assembly. The attachment assembly may comprise a lock that has a locked position and an unlocked position, and the lock in the locked position prevents longitudinal movement of the attachment assembly relative to the extended tab.
In another embodiment, an extended tab pedicle screw is provided. The pedicle screw comprises a screw shank and a housing attached to the screw shank. The housing comprises a plurality of frangible sections at different heights along the housing and two opposed side walls that define a transverse channel between them, the housing having a distal end nearest the screw shank and an opposite proximal end.
In some embodiments of the above pedicle screw, the screw shank may be cannulated. The plurality of frangible sections may be separated by scores on the side walls. The housing may further comprise a plurality of locking notches positioned longitudinally along the housing. At least two of the locking notches may be different sizes. A first locking notch may be distal to and wider than a second locking notch. Each locking notch may be wider than a more proximal locking notch or narrower than a more distal locking notch. The locking notches may also be identical.
In another embodiment, a minimally invasive surgical method for treating the spine of a patient is provided. The method comprises inserting a first screw into a first vertebra and a second screw into a second vertebra on an ipsilateral side of the patient, the first and second screws each comprising a shaft, a base portion and an extended tab portion comprising two tabs and a channel between the tabs, the extended tab portions extending above a skin level of the patient after the first and second screws are inserted. The method further comprises inserting a third screw into the first vertebra and a fourth screw into the second vertebra on a contralateral side of the patient, the third and fourth screws each comprising a shaft, a base portion and an extended tab portion comprising two tabs and a channel between the tabs, the extended tab portions extending above a skin level of the patient after the third and fourth screws are inserted. The method further comprises positioning blade assemblies over the first and second screws on the ipsilateral side, wherein the extended tab portions of the first and second screws extend above the upper surfaces of the blade assemblies. The method further comprises positioning one or more sleeves over the third and fourth screws on the contralateral side. The method further comprises attaching a retractor assembly to the blade assemblies and the one or more sleeves. The method further comprises removing upper portions of the extended tab portions of the first and second screws with remaining tab portions of the first and second screws positioned within the blade assemblies. The method further comprises distracting a disc space between the first and second vertebrae using the retractor assembly. The method further comprises inserting an interbody cage into the disc space on the ipsilateral side of the patient. The method further comprises removing the retractor assembly from the blade assemblies and sleeves. The method further comprises, after removing the blade assemblies from the first and second screws, inserting a first rod into the base portions of the first and second screws. The method further comprises, after removing the sleeves from the third and fourth screws, inserting a second rod into the base portions of the third and fourth screws. The method further comprises removing the remaining tab portions of the first and second screws from the base portions of the first and second screws. The method further comprises removing the extended tab portions of the third and fourth screws from the base portions of the third and fourth screws.
In some embodiments of the above method, the first and second screws may each comprise a plurality of frangible or weakened sections, and wherein removing the upper portions of the extended tab portions of the first and second screws and removing the remaining tab portions of the first and second screws from the base portions of the first and second screws causes separation along the frangible or weakened sections. The third and fourth screws may each comprise a frangible or weakened section between the extended tab portion and the base portion, and removing the extended tab portions of the third and fourth screws from the base portions of the third and fourth screws causes separation along the frangible or weakened section. The retractor assembly may attach to the blade assemblies through openings in arms of the retractor assembly. The retractor assembly may attach to the one or more sleeves with tubes attached to arms of the retractor assembly. Removing the upper portions of the extended tab portions of the first and second screws may occur before distracting the disc space. The method may further comprise delivering set screws through the channels between the tabs of the screws, the set screws engaging threads in the base portions of the screws to fix the rods in place. The method may further comprise positioning a medial blade between the blade assemblies of the first screw and the second screw.
In another embodiment, a minimally invasive surgical system for treating the spine is provided. The system comprises first and second bone anchors each comprising a threaded shaft, a base portion configured to receive a rod, and an extended tab portion comprising two tabs and a channel between the tabs, wherein the first and second bone anchors each further comprises a frangible or weakened section between the base portion and the extended tab portion, and the extended tab portion comprising a plurality of additional frangible of weakened sections. The system further comprises third and fourth bone anchors each comprising a threaded shaft, a base portion configured to receive a rod, and an extended tab portion comprising two tabs and a channel between the tabs, wherein the third and fourth bone anchors each further comprises a frangible or weakened section between the base portion and the extended tab portion. The system further comprises first and second blade assemblies each having a central bore configured to slide over the extended tab portions of the first and second bone anchors, respectively, wherein the first and second blade assemblies have a length that is shorter than a length of the extended tab portions. The system further comprises first and second sleeves each having a central bore configured to slide over the extended tab portions of the third and fourth bone anchors, respectively. The system further comprises a retractor assembly comprising a first arm and a second arm extending from a bar, wherein at least one of the arms is configured to move relative to the bar to change a distance between the arms. The first blade assembly and the first sleeve are configured to be attached to the first arm and the second blade assembly and the second sleeve are configured to be attached to the second arm.
In some embodiments of the above system, the arms may each comprise a first section and a second section that can articulate relative to each other. Each of the arms may comprise a collar configured to fit over a corresponding post of the first and second blade assemblies. The system may further comprise first and second tube assemblies attached to the first and second arms, respectively, wherein each tube assembly comprises a tube configured to slide over one of the first and second sleeves. The first and second blade assemblies may each further comprise an interior projection configured to fit between opposing tabs of the extended tab portions of the first and second bone anchors. The first and second blade assemblies may each further comprise wing or blade extensions extending from a central section of each blade assembly. The first and second blade assemblies may each further comprise a locking surface configured to engage notches on the first and second bone anchors. The system may further comprise a medial blade assembly attached to one or both arms, the medial blade assembly comprising a medial blade configured to be positioned between the first and second blade assemblies.
In another embodiment, a minimally invasive surgical system for treating the spine is provided. The system comprises a retractor assembly comprising a first arm and a second arm extending from a bar, wherein at least one of the arms is configured to move relative to the bar to change a distance between the arms. The system further comprises first and second blade assemblies configured to engage a first bone anchor inserted into a first vertebra and a second bone anchor inserted into a second vertebra, respectively, on an ipsilateral side of a patient, wherein the first blade assembly is configured to be attached to the first arm and the second blade assembly is configured to be attached to the second arm. The system further comprises an attachment assembly attached to the first and second arms and configured to connect to extensions extending from third and fourth bone anchors inserted into the first and second vertebrae, respectively, on a contralateral side of the patient. The blade assemblies are configured to engage the first and second bone anchors by sliding over extended tab portions of the first and second bone anchors.
In the embodiment of the system above, the system may further comprise first and second bone anchors each comprising a threaded shaft, a base portion configured to receive a rod, and an extended tab portion comprising two tabs and a channel between the tabs. The first and second bone anchors may each further comprise a frangible or weakened section between the base portion and the extended tab portion, and the extended tab portion comprising a plurality of additional frangible of weakened sections. The first and second blade assemblies may each further comprise an interior projection configured to fit between opposing tabs of the extended tab portions of the first and second bone anchors. The attachment assembly may comprise tubes configured to slide over the extensions extending from the third and fourth bone anchors. The system may further comprise third and fourth bone anchors each comprising a threaded shaft, a base portion configured to receive a rod, and an extended tab portion comprising two tabs and a channel between the tabs. The third and fourth bone anchors may each further comprise a frangible or weakened section between the base portion and the extended tab portion. The arms may each comprise a first section and a second section that can articulate relative to each other. Each of the arms may comprise a collar configured to fit over a corresponding post of the first and second blade assemblies. The first and second blade assemblies may each further comprise wing or blade extensions extending from a central section of each blade assembly. The first and second blade assemblies may each further comprise a locking surface configured to engage notches on the first and second bone anchors. The system may further comprise a medial blade assembly attached to one or both arms, the medial blade assembly comprising a medial blade configured to be positioned between the first and second blade assemblies.
In some embodiments, the minimally invasive (MIS) and maximal access (MAS) surgical techniques and apparatuses disclosed herein can include a retractor body 320 with a plurality of arms 350. The device as illustrated has two arms extending from a cross bar 322 of the retractor body. Generally, during a surgical procedure the cross bar 322 can be positioned above a patient's back and the arms 350 can point laterally on an ipsilateral or operational side of the patient's spine. As used throughout the present disclosure, the “operational side” shall refer to a side of the patient from which disc space of the spine is accessed (e.g., for delivery of a spinal implant). In some embodiments, the cross bar 322 can be positioned generally directly above the patient's spine or on the operational side of the patient's spine and the arms can point laterally. In some embodiments, the cross bar 322 can be positioned on a contralateral side (i.e., a side opposite the operational side) of the patient's spine and the arms can extend across the spine. In some embodiments, the cross bar 322 can be positioned above or adjacent the spine and the retractor body can have two arms extending laterally on the contralateral side and two arms extending laterally on the operational side, for a total of four arms. In some embodiments, the retractor body can have more than two arms on one or both sides.
The arms 350 can be configured to attach to anchor extensions, such as lateral blade assemblies 330, which can each be configured to attach to and extend from a bone anchor (typically a bone screw, such as a pedicle screw). Bone screws can attach to blade assemblies such that the shaft of the screw extends below the bottom edge of the blade. “Bottom” or “below” as used herein are with reference to the anterior side of the patient when the disclosed devices and components are positioned on or in the patient during posterior surgery. Thus, the bottom edge of a blade assembly 330 is the edge that would face the anterior side of the patient. The lateral blade assemblies 330 can be used to retract tissue during a surgical procedure. Additionally, because the lateral blades are attached to the pedicle screws, and because they can be configured to move with the arms in either direction along a generally caudal-cranial line when positioned in a patient (as described further below), they can also help distract disc space when the pedicle screws are screwed into adjacent vertebrae. Other types of anchor extensions can similarly be used to distract a disc space.
In some embodiments, a medial blade assembly 500 can be attached to the retractor body 320, such as to one or more of the arms 350. The medial blade 340 can be configured to move in a medial-lateral direction when placed within a patient, helping to retract tissue and create a clear view of the vertebrae. In some embodiments, the medial blade assembly can attach to the arms through attachment openings 354. As described in more detail below, the medial blade assembly can include an assembly attachment portion 510, a medial blade positioning portion 540, and a medial blade arm 342 that can attach to a medial blade 340.
In some embodiments, a retractor system can also include one or more anchor extension attachment assemblies 550. The extension attachment assemblies can be used to attach the retractor system to a variety of anchor extensions or surgical devices, such as one or more minimally invasive surgical (MIS) towers, as discussed further below. In some embodiments, a retractor body 320 can be positioned such that lateral blade assemblies 330 are on one side (e.g., an operational side) of a patient's spine and extension attachment assemblies 550 are on another side (e.g., a contralateral side) of the patient's spine.
Where the lateral blade assemblies are attached to pedicle screws on the operational side and the extension attachment assemblies interface with extensions (such as MIS towers) attached to pedicle screws on the contralateral side, separating the arms 350 of the retractor body 320 can create bilateral distraction, distracting the disc space on both sides of the spine. In some embodiments, the arms can be generally parallel to each other, such that the bilateral distraction creates a generally equal amount of distraction on both sides of the spine. In some embodiments, the arms can be at an angle relative to one another, such that bilateral distraction creates an amount of distraction on a first side of the spine that differs from the amount of distraction on a second side of the spine.
Having the retractor system 310 attached to anchor extensions on both sides of the spine creates a number of advantages. For example, the retractor system will be better anchored into the body. In some embodiments, the anchoring can be such that the system does not need to be anchored to the operating table or other external support structure, as is typically done. Further, where two screws are inserted into the operational side (one each on two adjacent vertebrae) and corresponding screws are inserted on the contralateral side, the retractor system can distribute forces between four screws instead of just two. Additionally, by allowing for distraction on both sides of the disc space, the retraction system described herein can be used to perform a TLIF, TPLIF, PLIF or other procedure according to the surgeon's choice without having to vary the setup.
In some embodiments, a surgeon can modify the device from the illustrated embodiment according to preference. For example, in some embodiments a surgeon may attach four extension attachment assemblies 550 to the arms 350 of the device. This could allow, for example, the surgeon to attach the retractor body to MIS towers on an operational side of a patient's spine and to MIS towers on a contralateral side of the patient's spine. Alternatively, in some embodiments a surgeon may elect to have two lateral blade assemblies on a first side of the spine and a lateral blade assembly and an extension attachment assembly on a second side of the spine. In some embodiments, the device may have four lateral blade assemblies. Alternate configurations may include more than two blade assemblies or extension attachment assemblies on one or both sides of the spine. According to another embodiment, shown for example in
With reference to
In some embodiments, it can be desirable to attach devices that allow for improved visibility of a surgical location. In some embodiments, lighting components 302 can attach to a retractor system 310 at any location that helps provide light to the surgical location without unduly obstructing the surgeon's view. For example, in some embodiments lighting components 302 can attach to the medial blade 340. Lighting components can attach to other portions of the retractor system 310 as well.
In some embodiments the retractor arms 350 can have a lateral blade connection assembly or collar 356, which can be used to attach the arms to a lateral blade assembly. The collar can have a variety of shapes. In the illustrated embodiment, the collar is configured to attach to a rectangular post of a lateral blade assembly, discussed further below. This can help ensure that the blade assembly is properly oriented when attached to a retractor arm 350.
The blade section 82 can have wings or blade extensions 88 that extend outward from opposite sides of the central section 84. The blade extensions 88 can extend below a bottom most point of the central section 84, creating a gap 81 as illustrated. In some embodiments, the blade extensions can extend straight out from the central section 84 in a common, shared plane. In some embodiments, the blade extensions can be curved and/or extend out at an angle from the central section. The blade extensions are preferably symmetric about a line perpendicular to the longitudinal axis of the central bore 86 of the blade 80. For reference purposes, the plane that is perpendicular to the blade extension line of symmetry, and on which the longitudinal axis of the central bore lies, can be referred to as the “blade plane.” In some embodiments, there are no blade extensions extending outward from the central section 84 and the central sections of adjacent retractor blades can provide access to a surgical site, with or without a medial blade assembly 42.
The attachment section 90 can extend from the blade section 82 and can be formed integrally with the blade section. Preferably, the attachment section extends from the blade section in a direction perpendicular to the blade plane. In some embodiments, the attachment section can have a lever bore 92 that extends at least partially into the attachment section from the same side as one of the blade extensions 88. The attachment section can also have a pin bore 96, which can extend into the attachment section from the central bore 86. In some embodiments, a longitudinal axis of the pin bore can be orthogonal to a longitudinal axis of the central bore. In some embodiments, a longitudinal axis of the lever bore 92 can be orthogonal to both the longitudinal axis of the pin bore 96 and the longitudinal axis of the central bore 86. The attachment section can also include a post attachment hole 94, a post pin hole 98, and a lever pin hole 93, as illustrated.
Preferably, the retractor blade 80, the retractor blade shaft 100, and a pedicle screw 60 are all sized and configured such that the threaded bottom 104 of the blade shaft can be screwed into the tulip 70 of the pedicle screw. The blade extensions 88 can be sized such that as the blade assembly 30 is screwed into the tulip the extensions slide into the openings 72 along the sides of the tulip (visible in
Because the blade assembly 30 can attach directly to the tulip 70 of the pedicle screw 60, the screw does not have to be installed in a patient in a modular fashion. Consequently, in some embodiments the screw can be installed in a patient as a preassembled or non-modular unit, saving the extra steps of attaching the tulips after performing or during the desired procedure. Further, in some embodiments the retractor blade shaft 100 can rotate within the central bore 86, allowing the blade assembly 30 to be screwed into the tulip 70 of a pedicle screw 60 without rotating the retractor blade 80 itself. Thus, in some embodiments the blade assembly 30 and pedicle screw 60 can be screwed together after the pedicle screw is placed within a vertebra. Further, because the blades can rotate, a single blade can be used regardless of the side of the disc space to which the blade is attached; if the blade needs to be rotated for proper positioning it can easily do so. This also can make it easier to perform surgical procedures on multiple spinal levels, as discussed further below.
In some embodiments, the blade assembly 30 can have a lever 110 that can be used to manually release the locking pin 130 from the locked position, thus allowing the retractor blade shaft 100 to unscrew from its position within a pedicle screw. As illustrated in
The lever can be held in position by the lever pin 114, about which the lever can rotate. Consequently, pushing the lever toward the blade extensions 88 will cause the end of the lever 112 to rotate toward the spring 32. The end of the lever will push against a surface bounding a gap (or gaps) 32 of the locking pin 130 and push it toward the spring, releasing the locking pin 130 from the locked position and moving it into an unlocked position in which the retractor blade shaft 100 can freely rotate in either direction and can be unscrewed from the pedicle screw. When the lever is released the spring will tend to push the locking pin back into the locked position.
Returning to
Also visible in
When the flexible sections 144 are in the unlocked position, the screw extender can be inserted into the cap 36 of the blade assembly 30 (visible in
The screw driver is preferably long enough to pass through the screw extender 140 and the bore 101 of the retractor blade shaft 100 in order to reach the shaft of a screw. The screwdriver has a distal tip 152 that can be configured to fit within a corresponding recess on the top of the screw shaft (e.g., a hex configuration), allowing the screwdriver to tighten the screw into a vertebra.
In some embodiments, it can be desirable to lock the screwdriver into a desired position within the screw extender 140 and blade shaft 100. This can be achieved by forming a plurality of annular recesses 154 on the outer surface of the screwdriver. The sections of the screwdriver with annular recesses can have a recessed diameter. The sections of the screwdriver between the annular recesses can have a standard diameter. The recesses can be used to lock the screwdriver against axial motion.
The locking plate can block at least some of the central bore 142 of the screw extender. In an unlocked position, the locking plate is positioned such that at least sections of the screwdriver with the standard diameter can pass freely through. In a locked position, as illustrated in
In some embodiments, the screw extender can include a spring 198 or other biasing member, which can bias the locking plate into the locked position. Consequently, as the screwdriver is fed through the screw extender, when an annular recess passes through the cutout 192 of the locking plate 190 the locking plate will be pushed into the locked position. This will prevent further withdrawal or entry of the screwdriver, because the sections of standard diameter above and below the annular recess will be blocked by the locking plate.
The screwdriver can still rotate, however. In some embodiments, to improve the ability of the screwdriver to rotate when locked into the screw extender, the radius of curvature of the section 193 of the cutout can be approximately equal to half of the recessed diameter.
As visible in
In some embodiments, it can be desirable to have a screwdriver that has the ability for more refined axial locking. For example, in some embodiments, manufacturing tolerances in various components, such as the screw extender length, the depth of the recess in the screw, and/or the blade assembly length, can combine to make it such that the screwdriver does not properly engage the screw in any of its locked positions. This risk can be minimized by increasing the number of annular recesses in the screwdriver and decreasing their width.
The screwdriver of
In some embodiments, the locking plate 190 and/or screwdriver 150 can receive a coating to increase its hardness and wear resistance. Coatings can include, for example, CrN, TiN, ZrN, a-C:H, etc. This can increase the life of the screwdriver and of the locking plate.
In some embodiments, a screw extender can have more than one locking plate 190 to engage the threaded section 156 of the screwdriver. This can help provide a more stable connection between the screw extender and screwdriver, while also increasing the durability of the system by sharing loads among multiple components. In some embodiments, having one or more locking plates engage the screwdriver on opposite sides can also help minimize loading on components by balancing loads on the screwdriver. This can further help the driver remain concentric with respect to the components of the screw extender.
Different arrangements are considered for engaging a screwdriver on multiple sides. For example, in some embodiments two separate springs can be used, each spring configured to engage a locking plate or a locking plate cover. In some embodiments, two locking plates can be positioned in the same plane on opposite sides of a screwdriver, and each locking plate can be spring biased into the screwdriver. Any other arrangement that biases a tooth into the screwdriver in more than one location can be used.
The various embodiments of screwdrivers and/or extenders described herein are not limited for use with a retractor system. They can be used in any surgical system that requires the use of a screwdriver and in which it may be beneficial to lock the screwdriver in a desired position. Such locking can, for instance, reduce the amount of toggle between the screw and screwdriver by ensuring a minimum engagement between the two. The various embodiments of screwdrivers and/or extenders described herein would have utility in any surgical system used to drive screws into bone, including but not limited to: pedicle screws such as for PLIF, TLIF, TPLIF and other surgeries; anterior cervical plates; posterior cervical systems; posterior lumbar systems; anterior lumbar systems such as standalone ALIF and ALIF plates; lateral plates; buttress plates; ISP plates; percutaneous screw systems; and other procedures.
In the illustrated embodiment, when the second flange portion is biased away from the first flange portion, the hook portion engages an edge of a slot in the arm and acts to couple the anchor extension attachment assembly to the arm of the retractor and resist movement of the anchor extension attachment assembly relative to the retractor arm. When movement of the anchor extension attachment assembly relative to the retractor is desired, a user can depress the second flange portion toward the first flange portion against the spring biasing force to rotate the second flange portion toward the first flange portion. Rotation of the second flange portion toward the first flange portion causes the hook portion to move out of engagement with the retractor arm and allows the anchor extension attachment assembly 550 to be moved relative to the retractor arm or removed from the retractor arm. When the anchor extension attachment assembly 550 is moved to a desired position, the user can release the pressure against the second flange portion and the spring force of the hinge portion will cause the second flange portion to engage the retractor arm and hold the anchor extension attachment assembly 550 in position relative to the retractor arm.
Other arrangements for engaging and disengaging the anchor extension attachment assembly 550 to the retractor arm are also possible. For example, a suitable flange and hinge arrangement to quickly and easily engage and disengage the anchor extension attachment assembly 550 to the retractor arm can include other mechanical engagements with the retractor arm.
In some embodiments, the tube assembly 580 can be configured to couple to an anchor extension that passes through the tube assembly. In some embodiments, the tube assembly 580 can be configured to attach to and tighten about an anchor extension that passes through the tube assembly. In some embodiments, the anchor extension passes through the tube assembly and can be oriented at varying angles.
In some embodiments, the medial blade assembly can attach to the arms through attachment openings 354 on the arms. As shown, in some embodiments, the attachment openings 354 are defined in portions of the retractor arm extending beyond a pivot location coupling one arm portion to another arm portion. The attachment openings 354 are configured to receive an arm connecting section 520 of the medial blade attachment assembly 510. The arm connecting section 520 can be configured to attach the medial blade assembly to one or more arms of a retractor system. In some embodiments, a medial blade assembly 500 can be configured to connect to an arm 350 via one or more connecting pins which can be positioned within one or more corresponding holes in an arm of the retractor system. In some embodiments, a medial blade assembly 500 can be configured to connect to an arm 350 without connecting pins and/or holes in an arm of the retractor system. The arm connecting section 520 can be adjustably connected to the retractor arms and/or a medial blade positioning section 540. For example, in some embodiments the arm connecting section 520 can have one or more grooves or notches 532 that can be positioned to receive one or more projections of the retractor arms and/or the medial blade positioning section 540 or pins or screws attached to the medial blade positioning section. This can allow the positioning section 540 to move relative to the retractor arms and/or the arm connecting section 520 along an axis of the grooves or notches.
A blade arm 342 can be attached to the medial blade positioning section 540. In some embodiments, the blade arm and positioning section can be integrally formed. In some embodiments, the blade arm and positioning section can cooperate to move relative to each other to move the medial blade. In some embodiments, an adjustment section 344 of the blade arm can be slideably positioned within an opening in the positioning section 540. In some embodiments an adjustment section 344 of the blade arm can comprise a threaded portion 345 configured to be coupled to an adjustment knob 347 positioned on an opposite side of the positioning section 540 and configured to control movement of the adjustment section 344 of the blade arm.
In some embodiments, the blade arm can be moved by sliding it along a longitudinal axis of the adjustment section through the opening in the positioning section 540. In some embodiments, turning the knob can engage threads on the adjustment section to cause the adjustment section to slide along its longitudinal axis. In some embodiments, the blade arm can be adjusted along two dimensions: moving the adjustment section 344 through the positioning section 540 along the longitudinal axis of the adjustment section, and moving the positioning section 540 and blade arm 342 along the longitudinal axis of the grooves or notches 532. Once the blade arm has been adjusted to a desired position, the knob in a stationary position can hold the position of the blade arm 342. In some other embodiments, a pin or screw can be tightened to lock the arm into the desired position.
The blade arm can also include a tool attachment section 346, to which tools can be attached before or after the blade arm has been moved into a desired position. The tool attachment section can have a variety of holes having a variety of configurations allowing the holes to receive a variety of tools. The tool attachment section 346 can additionally or alternatively have one or more blade attachment holes that can each be configured to receive a medial retractor blade.
As illustrated, in some embodiments the medial blade positioning section 540 can have a cutout 542 sized and configured to receive a blade arm 342. In some embodiments, blade arm 342 can have different sizes or configurations depending upon an expected desired positioning of the tool attachment section 346. For example, in some embodiments the blade arm can have one or more bends 343 which can affect the vertical positioning of the tool attachment section. In some embodiments, a bend can be used to lower the tool attachment section relative to the adjustment section 344. In some embodiments, a bend can be used to elevate the tool attachment section relative to the adjustment section.
The arms 350 can include a collar 356 that is sized to fit over the post 420 of a blade assembly 330. Preferably, the collar is oriented such that when a blade assembly is positioned within the collar, the blade plane (described above) is either generally parallel to or generally perpendicular to the cranial-caudal line of the patient or the cross bar 322 of the retractor body 320.
In some embodiments, the arms 350 can comprise a plurality of sections joined by articulating joints, and the most lateral sections can be configured to attach to the lateral blade assembly. In some embodiments, the arms 350 have a first section 472 and a second section 474, with the first section configured to connect to a lateral blade assembly. As illustrated, the first section 472 can articulate relative to the second section. In some embodiments, articulation can be locked, such as through the use of a screw, locking pin, or other device to hold the sections of the arms at a desired angle. The articulating arms allow the collar 356 to fit over the post 420 of a blade assembly 330 when the blade assembly has been angled away from the spine (such as when the surgeon desires to perform a TLIF) while still allowing the cross bar 322 to remain flat against the patient. This can minimize interference with or undesired forces on any anchor extensions attached to the retractor on the contralateral side and/or to the second section 474 of the arms 350.
In some embodiments, as described above, the retractor body can be configured to connect to a medial blade assembly 500 (such as that visible in
In some embodiments, a retractor body can have a second section 474 of the retractor arms 350 that can rotate relative to the cross bar 322 in addition to being able to rotate relative to the first section 472. Screws or pins can be used to tighten and/or lock one or more of the sections of the arms 350 relative to adjacent sections.
In some embodiments a surgeon may attach four extension attachment assemblies 704 to the arms of the device. This could allow, for example, the surgeon to attach the retractor body to extended tab percutaneous screws on an ipsilateral or operational side of a patient's spine and to towers on a contralateral side of the patient's spine. In some embodiments the retractor body is attached to extended tab percutaneous screws on either or both sides of the patient's spine. Spring-loaded tabs and/or levers 706 can engage arms of the retractor assembly to provide for adjustment in the positioning of the extension attachment assemblies along the retractor arms. As used herein, the term extended tab screw is a broad term and is used in its ordinary sense, and in some embodiments can refer to a screw that preferably extends beyond a patient's skin when the screw has been attached to a patient's vertebra. It is understood that the extended tab can refer to either integral features of the screw housing or removable features that serve the same purposes.
Many aspects of the retractor system 800 can be the same as or similar to aspects illustrated and/or described above. Unless otherwise noted, similarly numbered components will operate the same as or similar to those previously described. Thus, for example, in some embodiments a retractor system 800 can include a medial blade assembly 500 that can operate the same as that described with respect to
In some embodiments, the retractor body can attach to extended tab screws 702 via attachment assemblies, such as a tube assembly 780 that can be used on a contralateral side and/or a lateral blade assembly 830 that can be used on an operational side. It is understood that various different types of attachment assemblies can be used and that the illustrated attachment assemblies can be used on different sides of the spine. For example, in some embodiments the operational side can have one or more tube assemblies 780 that can be used to attach the screws on the operational side to the retractor body 320. In some embodiments, for example as illustrated, the tube assembly 780 can include an arm attachment portion 760 and a tubular portion 710 configured to be positioned around the extended tab screw 702.
In some embodiments, one or more sleeves can be positioned between an attachment assembly, such as the tube assembly 780, and an extended tab screw 702. For example, in some embodiments, a first sleeve 810 and a second sleeve or cap 820 can be positioned around a screw and the tubular assembly can slide over one or both of the sleeves. As described in more detail below, this can help allow for distracting disc space without accidentally breaking the extended tabs of the screw.
In some embodiments, the tube assembly 780 can include a tab or lever 706 with a hooked or projecting portion 708 that can be biased to move toward the tube 710. The projection 708 can fit within a groove or slot 476 on a portion of an arm 350, thereby attaching the tube assembly to the retractor body 320. In some embodiments, the tab or lever 706 can extend in a direction generally parallel to a longitudinal axis of the tube assembly. Pressing against the tab or lever can pivot the hook or projection 708 away from the tube 710 and out of the slot 476, thereby releasing the tube assembly and allowing for its removal. Having the tab or lever oriented in this way can make it easier for a surgeon to access and press the tab or lever to release the tube assembly. The tab can be pressed with the surgeon's hands and arms at an angle that minimizes interference with access to the surgical site.
In various embodiments, the extended portion 764 can include a variety of features that can assist with surgical procedures using the screw 702. For example, in some embodiments, the extended portion can include one or more frangible or weakened sections 750. In some embodiments, these sections can be score marks, areas of thinner material, or have other structural features such that the extended portion can break more easily at the weakened sections than at other sections of the extended portion 764. This can help with removing sections of the screw as needed during a surgical procedure, described in more detail below. In some embodiments, the lower most or distal most weakened section 750 can mark the boundary between the base portion 766 and the extended portion 764, such that the entirety of the extended portion 764 can be removed from the base portion if desired. In some embodiments, the extended tab screws on the operational side of the patient may be different from the extended tab screws on the contralateral side. For example, on the contralateral side the extended tab screws may have only one frangible or weakened section 750 marking the boundary between the base portion 766 and the extended tab section 764, as in some procedures it may only be desired to break off the extended tab portion 764 at this location. On the operational side, the extended tab screws may have a plurality of frangible or weakened sections 750 as shown in
In some embodiments, the screw 702 can also include one or more locking notches 752 positioned longitudinally along the screw. In some embodiments, the notches can extend perpendicular or generally perpendicular to the longitudinal axis of the screw. In some embodiments, for example as illustrated, the notches can traverse the channel 772.
The notches 752 can be used to help lock an attachment assembly, such as the lateral blade assembly 830, into a desired position along the screw 702. Examples are described further below. In some embodiments, each of the locking notches 752 can be generally the same size, shape, and/or depth. In some embodiments, the notches can have different shapes, sizes and/or depths. In some embodiments, each notch can have a different size, shape, and/or depth that corresponds to a particular size of attachment assembly, such as described further below.
In some embodiments, such as shown in
In some embodiments, a screw 702 can also include one or more attachment portions 774, preferably in the base portion 766. In some embodiments the attachment portions can include a recess, for example as illustrated. In some embodiments, the attachment portions can include a projection or other component. The attachment portions can be used to attach the screw to other components of a retractor system, such as an attachment assembly, sleeve, or tower.
The blade assembly can also include a post 840 that can be used to help attach the blade assembly to an arm 350 of the retractor body 320 (as shown for example in
In some embodiments, the lateral blade assembly can include at least one interior projection 832 that can be configured to fit between opposing tabs of an extended tab screw when the blade assembly is positioned around the screw. This can help the tabs retain their position and prevent them from flexing toward each other. Preferably, projection 832 can be configured to fit at a most distal end of the opening or gap 772 between tabs or prongs 778. Preferably, at least a portion of the central section 834 can extend distal to any gap or opening in the screw housing 770 and can be positioned against a distal end of the base portion 766. If the retractor body is used to apply a force on the screws through the lateral blade assemblies, such a distraction force is thus preferably not received entirely on the tabs 778. This can help prevent any distracting force from breaking the tabs (such as at the frangible portion 750) when not desired.
When the button 850 is in the unlocked position, the locking end 854 preferably does not engage the screw 702, thereby allowing the screw to move longitudinally relative to the blade assembly 830. In some embodiments, the button in an unlocked position does not extend into the central bore 836 of the assembly. In some embodiments, when the button is in an unlocked position a portion of the locking end may still extend into the central bore. The button can preferably be manually moved into the unlocked position, such as by pushing an actuation end 856 that can extend outward from the blade assembly. In some embodiments, the button can be biased into the locked position. For example, as shown in
In some embodiments, blade assemblies of different sizes can have buttons with locking ends 854 of varying shape, size, and/or width. In some embodiments, the locking end 854 of a particular blade assembly can be configured to fit and lock within only one set of notches 752 at a desired position on the percutaneous screw 702. In some embodiments, the notches 752 and locking ends 854 can be configured such that a locking end 854 of a particular blade assembly will not engage notches above a desired height. For example, in some embodiments the notches above the desired height may be too narrow to receive the locking end 854 (i.e., the locking end may be too thick to enter the notches). In some embodiments, locking notches may grow progressively larger (e.g., progressively wider so as to receive thicker aspects of the locking end) as they move down the screw housing. Preferably, blade assemblies are configured to lock with notches at a height such that when in use the blade assembly is lockable when a top of the blade assembly is generally level with a patient's skin.
In some embodiments, such as shown for example in
In some embodiments, the sleeve 810 can include a cut-out 814 in its base that is closed at its proximal end and open at its distal end. Preferably, the cut-out 814 is sized to receive a fusion rod and can be used to help position a fusion rod into a base 766 of a screw. In some embodiments, the fusion rod can be positioned within the opening or gap 772 of the screw housing 770 and moved to the distal end of the gap in the base 766 of the screw (shown in
Various embodiments of methods of using a retractor system to insert a spinal implant within a vertebral disc space are described. To begin, marks can be made on the positions on a patient's back that lie above both pedicles of the vertebrae on either side of the desired disc space. Using techniques known in the art, an incision is created on each marked spot. Either now, or later in the procedure, the surgeon can join the incisions on the same side of the spine. The surgeon can then use his or her finger to separate the muscle along the incision, preferably dissecting it along a single plane to make the healing process quicker and easier.
In some embodiments, a drill guide can be placed through the incision and onto the entrance to a pedicle. A drill can be advanced through the drill guide to drill a hole in the pedicle. A guide wire can then be inserted through the cannula of the drill guide and into the pedicle, and the drill guide can be removed. In some embodiments, the guide wire can be inserted through trocars, needles, or other hollow instruments instead of the drill guide.
The surgeon can select the desired bone screw and appropriate length lateral blade assemblies, such as lateral blade assemblies 30 or 330 described above with respect to
When the blade 30 is first inserted into the patient it is preferably oriented such that the blade plane (defined above) is parallel to the opening joining the incisions (i.e. generally parallel to the spine). Because the retractor blade shaft 100 (e.g.,
Once the blade, screw, extender, and screwdriver are in place, the screwdriver can be used to drive the screw into the pedicle. Preferably, only the screw shaft and the screwdriver will rotate, and the remaining components will maintain their orientation relative to the patient. Once the screw has been fully inserted into the bone, the screwdriver can be removed and then the extender can be removed. The blade assemblies can be rotated 90 degrees (either before or after removing the blade extender), such that the blade plane is generally perpendicular to the spine. This will retract tissue and create a visual and operational space in which the surgeon can operate. The guide wire can be removed at any point after the screw has begun to enter the pedicle.
This procedure can then be repeated for the opposite pedicle on the operational side. Additionally, if desired by the operating surgeon, instrumentation, such as pedicle screws with towers, can be inserted into the opposite pedicles on the contralateral side either before or after inserting the lateral blade assemblies on the operational side. As discussed above, additional arrangements of anchor extensions can be used, such as using MIS towers instead of lateral blade assemblies.
Once all desired pedicle screws have been placed (e.g., two with blade assemblies on the operational side and two with towers on the contralateral side), the retractor body can be positioned over the patient's back and attached to the towers and lateral blades. If the surgeon desires to adjust the angle of the lateral blades, this can be done without affecting the positioning of the retractor body due to the articulated arms, as discussed above. In some embodiments, the surgeon can rotate the lateral blade assemblies by approximately 90 degrees to help establish an operational corridor. This can be done either before or after attaching the blades to the retractor body, or before or after adjusting the angle of the blades. In some embodiments, once an operational corridor has been established a surgeon may desire to improve access to an intervertebral space, such as by performing a facetectomy. The retractor body can distract the disc space by moving the arms of the retractor apart.
If desired, the surgeon can position a medial blade between the two lateral blades and attach the medial blade to the retractor. The medial blade can then be moved medially, retracting more tissue and broadening the visual and operational space. The standard TLIF, PLIF, TPLIF, or other procedures can then be performed. Following the procedure, the blades can be unscrewed from the pedicle screws in the same manner in which they were attached. If desired, rods can be inserted to join the pedicle screws, and the rods can be locked into place with set screws, as discussed above. Rods can also be inserted to join pedicle screws on the contralateral side, and the towers can be removed from the pedicle screws on that side.
If the surgeon desires to perform the procedure on multiple adjacent levels, then additional screws can be inserted in the next level using the same methods described above. This can be done before or after performing the methods described above. One advantage of this system is that the lateral blade assemblies can be symmetrical and can be used on either the cranial or caudal side of the operation (also referred to as the left or right side, from the surgeon's point of view). Thus, the blade or other anchor assembly adjacent the newly inserted pedicle screw on the operational side does not need to be removed and replaced, but can instead be rotated 180 degrees if necessary. The procedure can then proceed as described above.
Once the screws have been positioned within the spine, instrumentation can be inserted over the screws, such as shown in
Preferably, a blade assembly of a desired height is selected such that an upper surface of the blade assembly, such as the section 831 (
With reference to
For example, the posts 840 of blade assemblies 830 can be inserted through openings 473 in the arms. In some embodiments, the openings 473 can have approximately the same cross-sectional size and shape as a cross section of the posts 840 at projections 842 (shown in more detail in
In some embodiments, the arms 350 can attach directly to a sleeve, such as the sleeve 810. In some embodiments, for example as shown in
In some embodiments, before or after operating the retractor body 320 to distract the disc space, a portion of the screws 702 extending past the blades 830 on the operational side can be removed. This can lower the height of the screw and help limit any interference in access to the spinal disc space from screws extending past the blades.
After the disc space has been distracted using the retractor, an optional procedure to improve access to the intervertebral space (e.g., a facetectomy) may be performed. An interbody cage may then be inserted into the disc space through the ipsilateral side. Once the desired procedure has been completed, the retractor body and any instrumentation inserted over the screws can be removed, for example as shown in
Although the foregoing description of the preferred embodiments has shown, described and pointed out the fundamental novel features of the invention, it will be understood that various omissions, substitutions, and changes in the form of the detail of the apparatus as illustrated as well as the uses thereof, may be made by those skilled in the art, without departing from the spirit of the invention.
Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures or characteristics of any embodiment described above may be combined in any suitable manner, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments.
Similarly, it should be appreciated that in the above description of embodiments, various features of the inventions are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that any claim require more features than are expressly recited in that claim. Rather, as the following claims reflect, inventive aspects lie in a combination of fewer than all features of any single foregoing disclosed embodiment. Thus, the claims following the Detailed Description are hereby expressly incorporated into this Detailed Description, with each claim standing on its own as a separate embodiment.
This application claims the priority benefit of U.S. Provisional Application Nos. 61/933,272, filed Jan. 29, 2014, and 62/046,635, filed Sep. 5, 2014, each of which is hereby incorporated by reference herein in its entirety. Additional features and aspects of some advantageous systems and methods that may be utilized in combination with embodiments found in this application are described in U.S. patent applications incorporated by reference herein, including, for example, U.S. Provisional Application No. 61/676,856, filed Jul. 27, 2012, and U.S. patent application Ser. No. 13/952,324, filed Jul. 26, 2013, published as US 2014/0031874 A1, which are expressly incorporated by reference herein in their entireties so as to form part of this specification.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US15/13188 | 1/28/2015 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 61933272 | Jan 2014 | US | |
| 62046635 | Sep 2014 | US |
