The present invention relates to medical devices such as spinal intervertebral implants implanted between adjacent vertebral bodies of a spinal column section, and more particularly to a medical implant for intervertebral stabilization comprising a flexible implant section which enables bending or pliancy of the implant body to thereby facilitate insertion of the spinal implant at a selected disc space via a spinal surgical procedure.
The spine is divided into four regions comprising the cervical, thoracic, lumbar, and sacrococcygeal regions. The cervical region includes the top seven vertebral bodies or members identified as C1-C7. The thoracic region includes the next twelve vertebral members identified as T1-T12. The lumbar region includes five vertebral members L1-L5. The sacrococcygeal region includes nine fused vertebral members that form the sacrum and the coccyx. The sacrum region includes five fused vertebral members S1-S5, with S1 being adjacent to L5. The vertebral members of the spine are aligned in a curved configuration that includes a cervical, thoracic and lumbosacral curve. Within the spine, intervertebral discs are positioned between the vertebral members and permit flexion, extension, lateral bending, and rotation. An intervertebral disc functions to stabilize and distribute forces between vertebral bodies. The intervertebral disc is comprised of the nucleus pulposus surrounded and confined by the annulus fibrosis.
Intervertebral discs and vertebral members are prone to injury and degeneration. Damage to the intervertebral discs and/or vertebral members can result from various physical or medical conditions or events, including trauma, degenerative conditions or diseases, tumors, infections, disc diseases, disc herniations, aging, scoliosis, other spinal curvature abnormalities or vertebra fractures. Damage to intervertebral discs can lead to pain, neurological deficit, and/or loss of motion. Damaged intervertebral discs may adversely impact the normal curvature of the spine, and/or lead to improper alignment and positioning of vertebrae which are adjacent to the damaged discs. Additionally, damaged discs may lead to loss of normal or proper vertebral spacing.
Various known surgical procedures, treatments and techniques have been developed to address medical problems associated with damaged or diseased intervertebral discs. One treatment is a fusion procedure which partially removes the center or nuclear area of a damaged disc and fuses adjacent vertebral members to prevent relative motion between the adjacent vertebral bodies. A section of the disc, annulus and nucleus, is removed or cut out to allow insertion of a spinal implant or spacer. The spacer may be used in conjunction with bone graft or allograft material which enables the adjacent vertebrae to grow and fuse together. Existing spinal implants assist in maintaining disc space height during the fusion process while at the same time, permitting or enabling an element of compression and selective movement of the implant within the disc space while vertebral fusion is taking place. The implant or spacer may also assist in imparting desired alignment or lordosis of the adjacent vertebral bodies.
As is known to persons of skill in the art, there are a variety of structures and configurations which can be used to obtain the desired vertebral body spacing and alignment such as spacers, implants or cages. These structures come in a variety of configurations, features, contours, geometries and sizes depending on the specific medical application or use. Further, implants can be inserted from a variety of insertion approaches, including for example anterior, posterior, anterolateral, lateral, direct lateral and translateral approaches.
In the area of surgical procedures for spinal implants at the L4-L5 or the L5-S1 level, an implant is often inserted in the disc space via either an anterior or posterior approach. Delivery and insertion of a spinal implant into the L4-L5 or L5-S1 disc space via a lateral approach can be done, but is less common and more difficult to perform than other procedures such as anterior or posterior procedures. One reason for the difficulty in inserting an implant at the L4-L5 or L5-S1 level via a later approach surgical procedure is the anatomical position of the iliac crest relative to the position of the L4-L5 or L5-S1 disc space level.
The anatomical position and curved nature of the iliac crest relative to the vertebral disc space at L4-L5 or L5-S1 makes the iliac crest a physical obstruction to direct or straight access to the L4-L5 or L5-S1 disc space in a lateral surgical approach procedure. The iliac crest's position prevents a direct or straight angle of approach for delivery, entry and insertion of a spinal implant into the L4-L5 or L5-S1 vertebral disc space. Additionally, at the L4-L5 or L5-S1 disc space levels, as well as higher lumbar spine levels, there is a complexity of neurological and vascular structures that cross the implant delivery approach path or implant path of insertion. In order to clear the obstructing iliac crest, and neurological and vascular structures, for implant insertion at L4-L5 or L5-S1, via a lateral or direct lateral approach, the implant is typically delivered to the disc space at some angled lateral angle of approach.
An additional difficulty in a lateral approach procedure is that since an implant is delivered at some lateral angle of approach, the implant being inserted arrives at L4-L5 or L5-S1 in an angled orientation. It would be easier and more convenient for the implant to enter the disc space in as nearly a direct or straight lateral approach as possible. In order to do this, an implant being inserted into the disc space will have to turn or navigate a corner at the entry of the L4-L5 or L5-S1 disc space so that the implant can enter the disc space in a substantially lateral approach orientation. A drawback of existing implants is that many are rigid or have inflexible physical configurations which prevent the implant from being able to be turned or navigated around a corner. The rigid aspect of existing implant configurations makes it difficult to use or impractical to insert these rigid implants via a lateral approach procedure at L4-L5 or L5-S1. Such difficulties limit the number of lateral approach implant procedures at L4-L5 or L5-S1 and the number of surgeons who can perform such a lateral approach implant procedure.
There is a need for an improved intervertebral implant, and method for inserting an implant between adjacent vertebral bodies using minimally invasive surgical techniques, that overcomes drawbacks and difficulties in delivering and inserting an implant at a desired or selected disc space via a spinal surgical procedure.
There is provided a spinal implant for insertion into an intervertebral disc space for intervertebral stabilization comprising a flexible implant section which enables bending or pliancy of the implant body to thereby facilitate insertion of the spinal implant into the disc space via a spinal surgical procedure.
There is provided a spinal implant for insertion into an intervertebral disc space comprising a flexible implant section which enables bending or pliancy of the implant body to thereby facilitate insertion of the spinal implant via a spinal surgical procedure, including, among others, a direct lateral lumbar interbody fusion (DLIF) procedure, a posterior lumbar interbody fusion (PLIF) procedure or a transforaminal lumbar interbody fusion (TLIF) procedure.
There is also provided a spinal implant for insertion into a disc space comprising a leading end, a trailing end and a flexible section connecting the leading end and the trailing end, wherein the implant is deformable at the flexible section to thereby permit a substantially straight lateral entry of the implant into a selected disc space. The implant is delivered to the selected disc space at an insertion angle of approach. The implant can have a leading end comprising a bullet shaped configuration. Further, the flexible section may be comprised of flexible or pliant material, at least one pivoting connection or a spring mechanism.
There is further provided a spinal implant for insertion into a selected disc space comprising, a leading end, a trailing end, a flexible section connecting the leading end and the trailing end and a central implant aperture bounded by the leading end, the trailing end and the flexible section. In one aspect, the implant is delivered at a lateral insertion angle of approach via an implant insertion channel. The implant is deformable or pliant about the flexible section through interaction with the implant insertion channel to thereby permit substantially straight lateral entry of the implant into the selected disc space via a lateral approach. Further, the flexible section may be comprised of flexible or pliant material, at least one pivoting connection or a spring mechanism.
There is also provided a spinal implant for insertion into an intervertebral disc space comprising a leading end, a trailing end flexibly connected to the leading end and a locking mechanism adapted to lockingly engage the spinal implant to prevent motion between the leading end and trailing end. The implant is deformable about a flexible section to thereby permit a substantially straight entry of the implant into a selected disc space. The locking mechanism comprises a leading end locking passage, a trailing end locking passage which substantially aligns with the leading end locking passage when the implant is inserted in the selected disc space, and a locking member adapted to be inserted into the leading end locking passage and trailing end locking passage. The locking mechanism is engaged when the locking member spans the flexible section at a pivotal connection and is at least partially inserted into both the substantially aligned leading end locking passage and trailing end locking passage thereby preventing motion between the leading end and the trailing end. The locking member is secured in both the aligned leading end locking passage and trailing end locking passage through a friction fit or interference fit. The locking member is adapted to cooperatively deform to facilitate insertion of the locking member into the aligned leading end locking passage and trailing end locking passage. The leading end locking passage, the trailing end and the locking member have complimentary and cooperative configurations to enable the locking member to be inserted into the aligned leading end locking passage and trailing end locking passage. Moreover, the leading end and trailing end can form a front to back wedge configuration which is adapted to alleviate coronal spinal deformity when the spinal implant is inserted in the selected disc space. Alternatively, the leading end and trailing end can form a lateral side-to-side wedge configuration which is adapted to alleviate sagittal spinal deformity when the spinal implant is inserted in the selected disc space.
There is further provided an implant system for insertion into an intervertebral disc space comprising a spinal implant deformable about a pivotal connection to thereby permit a substantially straight entry of the implant into a selected disc space. The spinal implant comprises a leading end including a leading end locking passage, a trailing end pivotally connected to the leading end, and having a trailing end locking passage which substantially aligns with the leading end locking passage when the implant is inserted into a selected disc space. The implant system also comprises a locking member adapted to be inserted into the leading end locking passage and trailing end locking passage to lockingly engage the spinal implant to prevent motion between the leading end and trailing end. In locking engagement, the locking member spans the pivotal connection and is at least partially inserted into both the substantially aligned leading end locking passage and trailing end locking passage thereby preventing motion between the leading end and the trailing end. The locking member is secured in both the aligned leading end locking passage and trailing end locking passage through a friction fit or interference fit. Also, the locking member is adapted to cooperatively deform to facilitate insertion of the locking member into the aligned leading end locking passage and trailing end locking passage.
Disclosed aspects or embodiments are discussed and depicted in the attached drawings and the description provided below.
The present invention relates to medical devices such as spinal intervertebral implants implanted between adjacent vertebral bodies, and methods of use, and more particularly to a spinal implant for intervertebral stabilization of a spinal disc space via insertion of a flexible or pliant implant at a desired disc space. For purposes of promoting an understanding of the principles of the invention, reference will now be made to one or more embodiments or aspects, examples, drawing illustrations, and specific language will be used to describe the same. It will nevertheless be understood that the various described embodiments or aspects are only exemplary in nature and no limitation of the scope of the invention is thereby intended. Any alterations and further modifications in the described embodiments or aspects, and any further applications of the principles of the invention as described herein are contemplated as would normally occur to one skilled in the art to which the invention relates.
While
Referring to
The leading end 32 has a physical shape or physical configuration adapted to facilitate or ease implant insertion into the disc space L5-S1. In a preferred aspect, shown in
The trailing end 36 of the flexible implant 30 preferably comprises an implant grip or attachment section 40 situated at the proximal implant end 37 which enables the coupling of an insertion instrument (not shown). The attachment section 40 enables the controlled delivery of the flexible implant 30 into the L5-S1 disc space via a lateral surgical approach. In a preferred aspect, the attachment section 40 is recessed into the trailing end 36 such that when an instrument (not shown) is coupled to the flexible implant 30, the instrument is entirely interior to or flush with the exterior surface of the proximal implant end 37. In one aspect, the attachment section is a recessed slot 40 on both sides of the proximal implant end 37.
The flexible section 34 preferably connects the leading end 32 and the trailing end 36 to form the flexible spinal implant 30. The flexible section 34 is preferably located at a mid portion of the flexible spinal implant 30. However, those of skill in the art will recognize that the flexible section 34 may be located at other positions of the flexible spinal implant 30 as may be desired or required by a physician or patient anatomy, or the needs or requirement of a medical procedure. The flexible section 34 is coupled or attached between the leading end 32 and the trailing end 36 so as to form a single assembled flexible spinal implant 30. The flexible section 34 is the aspect that permits or enables the implant 30 to bend, flex or pivot at or about the implant's mid portion when the implant is being inserted into the L5-S1 disc space via a preferred later surgical approach.
The flexible section 34 also permits the implant 30 to be fully flexible in any one or more dimensional directions in space such that the flexible implant 30 can travel, or rotate, at or about the flexible section 34 to permit the flexible implant 30 to be delivered and inserted into the desired or selected disc space in a substantially straight approach orientation. In this manner, the flexible implant 30 is manufactured to have the physical properties or characteristics so that it can travel, bend, pivot or rotate about or at one or more reference lines, planes or axes A1, A2 and A3, e.g., as those shown and discussed with respect to
Those of skill in the art will recognize that the flexible section 34 can be comprised of any bio compatible and flexible material that will permit the implant 30 to bend, deform, pivot or flex about or at the flexible section 34. For example, it may be a deformable plastic, an elastic polymer, an elastomer, rubber or another deformable or elastic material. Further, in one aspect, the flexible implant 32 may be manufactured to have properties or characteristics such that such that the flexible section 34 can or will become rigid or substantially rigid once the implant 30 is fully implanted in the disc space. The flexible section 34 can also be manufactured to become rigid at a desired time or over time after implant insertion. For example, as soon as the implant is inserted in the disc space, over a desired or predetermined time period, or as the fusion is setting. The flexible implant 32 once rigid would thereafter no longer maintain implant flexibility. In one aspect, the implant rigidity characteristic may be provided through the use of shape memory nitinol or other shape memory materials which can reach rigidity in a patient anatomical environment. This aspect or property may be used where desired or required by a patient's anatomy or a physician's requirement.
In a lateral approach procedure, the flexible implant 30 arrives at the L5-S1 disc space entry 28 at the angle of approach or insertion angle of approach Z. Prior to implant insertion, the intervertebral disc space is typically prepared with a partial or complete discectomy in order to accept the flexible spinal implant which is to be inserted. In order to minimize damage to the vertebral bodies L5 and S1 and to facilitate entry of the implant into the L5-S1 disc space, it is preferred that the implant enter the L5-S1 disc space in a straight or substantially straight lateral approach orientation. Since the implant 30 arrives at the disc space entry 28 at the angle of approach Z, the implant must bend, deform or deflect such that the implant can enter the L5-S1 disc space in a substantially straight lateral approach orientation. The novel flexible section 34 enables or permits the implant 30 to bend, deform or deflect at or about the flexible section 34 as needed to thereby enable or permit the substantially straight lateral approach entry of the implant 30 into the selected disc space when using a lateral approach procedure.
The ability of the flexible implant to approach and enter the selected disc space in a lateral approach, as opposed to an angled approach results in reduction or minimization of damage or potential damage to the affected vertebral bodies L5 and S1 at the L5-S1 disc space, or to any set disc space vertebral bodies where a flexible implant is delivered and inserted. One advantageous feature of this aspect is that due to the lateral or substantially straight lateral approach of the flexible implant at the disc space, the affected vertebral body endplates be protected against endplate stress and/or fractures that are typically associated with non-flexible or rigid implants which lack the flexibility to transition from a delivery having an angle of approach and reach the disc space and corresponding vertebral bodies and end plates in a lateral or substantially straight lateral orientation. This would in turn reduce or minimize the incidence of post implantation implant subsidence due to endplate stress and/or endplate stress fractures when the endplates are stressed or fractured by a non-flexible or rigid implant which is unable flex and transition from a delivery having an angle of approach to a lateral or substantially straight lateral orientation. The configuration of a non-flexible or rigid implant being delivered at an angle of approach imparts greater implant stresses or forces on a smaller end plate surface area which can result in endplate stress and/or endplate stress fractures which can go undetected until subsequent x-ray imaging reveals the subsidence of the inserted implant. The flexible implant of the present disclosure alleviates or eliminates this drawback of rigid or non-flexible implants.
In this manner, the flexible implant 30 is adapted to bend and turn away from its delivery path orientation, having an insertion angle of approach Z, and enter the disc spaced L5-S1 in a substantially straight lateral approach orientation. As the flexible implant 30 is being delivered, via an instrument attached to the rear attachment section 40 (not shown), the leading end 32 of implant reaches and encounters an obstructing and opposing force at the S1 vertebrae at the disc space entry 28. That opposing force will tend to prevent or retard the entry of the implant into the disc space. This difficulty is overcome in a two fold manner. First, the curved or bullet shaped configuration 38 of the leading end 32 facilitates a smoother entry into the disc space L5-S1 and provides a curved or rounded contour that will facilitate entry and impart distraction of the vertebral bodies L5 and S1 as the implant continues to travel into the disc space. Secondly, the opposing force encountered due to the insertion angle of approach Z is translated through the leading end 32 to the flexible section 34. The flexibility or pliancy of the flexible section 34 permits or enables the implant 30 to bend, deform or deflect as needed about or at the flexible section 34. In this manner, the leading end 32 and the trailing end 36 of the flexible implant 30 will swing or rotate towards a straight lateral orientation that thereby permits the flexible implant 30 to enter the L5-S1 disc space in a substantially straight lateral manner as the implant continues to be inserted or pushed into the disc space L5-S1 by a surgeon. The flexible implant 30, via the flexible section 34, will “self balance” and settle into or reach an equilibrium fit or best fit in the interbody disc space after implant insertion through motion and/or micro motion of the flexible section 34 until the flexible implant 30 settles into the best anatomic fit in the disc space. Once the flexible implant 30 is inserted, the coupled instrument (not shown) can be disconnected from the attachment section 40. In one aspect, the flexible implant 30 will become rigid or substantially rigid once the implant is fully implanted in the disc space at desired time after implant insertion. For example, as soon as the implant 30 is inserted in the disc space, over a desired or predetermined time period, or as the fusion is setting. In one aspect, the implant rigidity characteristic may be provided through the use of shape memory nitinol or other shape memory materials which can reach rigidity in a patient anatomical environment. This aspect or property may be used where desired or required by a patient's anatomy or a physician's requirement.
In the depicted lateral approach of
The flexible implant 60 further also comprises anti-back out protrusions 72 on the upper and lower surfaces 80, 82, 84 and 86, and an instrument attachment section 70. The anti-back out protrusions 72 extending from the upper and lower surfaces 80, 82, 84 and 86 will be configured and oriented so as to prevent the implant 60 from backing out or being ejected after insertion into the disc space. In the aspect shown in
The leading end 62 has a physical configurations adapted to facilitate insertion into the disc space L5-S1. In one aspect, the leading end 62 has a curved or bullet shaped surface 68 which facilitates insertion of the flexible implant 60 in the L5-S1 disc space. The curved or bullet shaped nose 68 will impart a distracting force between the L5-S1 disc space to facilitate insertion of the flexible implant 60. The trailing end 66 comprise an implant grip or attachment section 70 situated at the proximal implant end 77 which enables the coupling of an insertion instrument (not shown). The attachment section 70 enables for the controlled delivery of the flexible implant 70 into the L5-S1 disc space via a lateral approach. The attachment section 70 is preferably a recessed into the trailing end 66 such that when an instrument is coupled to the flexible implant 60, the instrument is entirely interior to the exterior surface of the proximal implant end 67. In one aspect, the attachment section is a recessed slot 70 on both sides of the proximal implant end 67.
The flexible section 64 preferably connects the leading end 62 and the trailing end 66 to form the flexible spinal implant 60. The flexible section 64 is preferably located at a mid portion of the flexible spinal implant 60. However, those of skill in the art will recognize that the flexible section 64 may be located at other positions of the flexible spinal implant 60 as may be desired or required by a physician or patient anatomy, or the needs or requirement of a medical procedure. The flexible section 64 is coupled or attached between the leading end 62 and the trailing end 66 so as to form a single assembled flexible spinal implant 60. The flexible section 64 permits or enables the implant to bend, flex or pivot at or about the flexible section 64 when the implant is being inserted into the L5-S1 disc space via a preferred later surgical approach.
The flexible section 64 also permits the implant 60 to be fully flexible in any one or more dimensional directions in space such that the flexible implant 60 can travel or rotate at or about the flexible section 64 to permit the implant 60 to be delivered and inserted into the desired or selected disc space in a substantially straight approach orientation. In this manner, the flexible implant 60 is manufactured to have the physical properties or characteristics so that it can travel, bend, pivot or rotate about or at one or more reference lines, planes or axes A1, A2 and A3, e.g., as those shown and discussed with respect to
The flexible section 64 can be comprised of a biocompatible and flexible material that will permit the implant to bend or flex about or at the mid section 64. For example, a deformable plastic, an elastic polymer, an elastomer, rubber or another elastic material. In one aspect, the flexible implant 60 may be manufactured to have properties or characteristics such that such that the flexible section 64 can or will become rigid or substantially rigid once the implant is fully implanted in the disc space. The flexible implant section 64 can be manufactured to become rigid at a desired time or over time after implant insertion. For example, as soon as the implant is inserted in the disc space, over a desired or predetermined time period, or as the fusion is setting. In one aspect, the implant rigidity characteristic may be provided through the use of shape memory nitinol or other shape memory materials which can reach rigidity in a patient anatomical environment. The flexible implant 60 once rigid would thereafter no longer maintain implant flexibility. This aspect or property may be used where desired or required by a patient's anatomy or a physician's requirement.
The leading end 105 is pivotally connected to the first member 110 at a first hinge 112 to thereby permit rotational motion between the leading end 105 relative to the first member 110. The first member 110 is pivotally connected to the second member 120 at a second hinge 115 to thereby permit rotational motion of the first member 110 relative to the second member 120. The first member 110 is pivotally connected to the third member 125 at a third hinge 117 to thereby permit rotational motion of the first member 110 relative to the third member 125. The trailing end 135 is pivotally connected to the second member 120 at a fourth hinge 130 to thereby permit rotational motion of the trailing end 135 relative to the second member 120. The trailing end 135 is pivotally connected to the third member 125 at a fifth hinge 127 to thereby permit rotational motion of the trailing end 110 relative to the third member 125.
As shown in
The trailing end 135 comprises an implant grip or attachment aperture 145 situated at the proximal implant end 137 which enables the coupling of an instrument (not shown) to the flexible spinal implant 100. The attachment aperture 145 enables an instrument to couple to the flexile spinal implant 100 for delivery of the flexible implant 100 through an implant insertion channel 160 into a selected disc space via a lateral approach. After insertion of the flexible implant 100, the attachment aperture 145 can also be used to insert graft material, as discussed previously, if none was packed in prior to implant insertion.
The flexible spinal implant 100 further comprises an interior implant aperture 150 defined and formed by the pivotally connected first member 110, second member 120, third member 125 and trailing end 135. The interior implant aperture 150 can be filled or packed with graft material before or after insertion of the flexible implant 100 into the selected disc space. The graft material may be composed of material that has the ability to promote, enhance and/or accelerate bone growth and fusion of vertebral bodies. Graft material may include allograft material, bone graft, bone marrow, demineralized bone matrix putty or gel and/or any combination thereof. The filler graft material may promote bone growth through and around the interior implant aperture 150 to promote fusion of the disc space intervertebral joint. Those of skill in the art will recognize that the use of filler graft material is optional, and it may or may not be used depending on the needs or requirements of a physician or a medical procedure.
The first member 110, second member 120 and third member 125 are pivotally connected to each other and to the leading end 105 and trailing end 135 to form the multi-piece flexible implant 100 shown in
In one aspect, the flexible implant 100 may be manufactured to have properties or characteristics such that the pivoting connections 112, 115, 117, 127 and 130 can or will become rigid or substantially rigid once the implant 100 is fully implanted in the disc space. The pivoting connections 112, 115, 117, 127 and 130 can be manufactured to become rigid at a desired time or over time after implant insertion. For example, as soon as the implant is inserted in the disc space, over a desired or predetermined time period, or as the fusion is setting. The pivoting connections 112, 115, 117, 127 and 130, once rigid, would thereafter no longer permit the implant 100 to maintain implant flexibility. In one aspect, the implant rigidity characteristic may be provided through the use of shape memory nitinol or other shape memory materials which can reach rigidity in a patient anatomical environment. This aspect or property may be used where desired or required by a patient's anatomy or a physician's requirement.
The flexible implant 100 of
The implant insertion channel 160 transitions from the first channel end 163 to the channel turn section 164 and then to the second channel end 167, as shown in
In a preferred aspect, the flexible implant 100 travels inside the implant insertion channel 160, as shown in
The leading end 205 has a physical configuration adapted to facilitate or ease insertion of the flexible implant 200 into a disc space. In a preferred aspect, shown in
The flexible spinal implant 200 further comprises an interior implant aperture 230 defined by the pivotally connected leading end 205, first member 210, second member 215 and trailing end 220. The interior implant aperture 230 can be filled with a graft material before insertion of the flexible implant 200 into a selected disc space. The graft material may be composed of material that has the ability to promote, enhance and/or accelerate bone growth and fusion of vertebral bodies. The graft material may promote bone growth through and around the interior implant aperture 230 to promote fusion of the disc space intervertebral joint. The use of filler graft material is optional, and it may or may not be used depending on the needs or requirements of a physician or a medical procedure.
The flexible implant 200 also comprises anti-back out protrusions 225 on the upper and lower surfaces of the flexible implant 200. The anti-back out protrusions 225 extending from the upper and lower surfaces are preferably configured and oriented so as to prevent the implant 200 from backing out or being ejected after insertion into a disc space. In the aspect shown in
The first member 210 and second member 215 are pivotally connected to each other and to the leading end 205 and trailing end 220 to form the multi-component flexible implant 200 shown in
In a further aspect contemplated for the flexible implants 250, 260, 270, 400, 410 and 420, shown in
The flexible spinal implant 300 can be delivered and inserted into a desired disc space via a lateral approach procedure, such as a DLIF procedure, to clear the obstructing iliac crest, and neurological and vascular structures. The flexible spinal implant 300 may also be delivered and inserted into a desired disc space via a PLIF or TLIF procedure to bend around and safely bypass or clear the cauda equina. In one aspect, the flexible spinal implant 300 is delivered via or through a minimal access spinal technology (MAST) surgical technique or procedure. Those of skill in the art will recognize that the flexible spinal implant 300 may also be delivered and inserted via other known surgical approaches, including, a posterior, direct lateral, translateral, posterolateral, or anterolateral or any suitable oblique direction. Some known techniques and approaches that may be used to insert the flexible implant 300 may also include, among others, anterior lumbar interbody fusion (ALIF). Further, those of skill in the art will recognize that a spinal implant may be delivered and inserted through known surgical technique and procedures, including: open, mini-open or other minimally invasive surgical (MIS) techniques.
The flexible section 310, shown in
The flexible section 310 thereby permits the implant 300 to be fully flexible, deformable or moveable in any one or more dimensional directions in space such that the flexible implant 300 can travel, bend, pivot or rotate at or about the flexible section 310 to permit the flexible implant 300 to be delivered and inserted into the desired or selected disc space in a substantially straight approach orientation. In this manner, the flexible implant 300 has the physical properties or characteristics so that it can travel, bend, pivot or rotate about or at one or more reference lines, planes or axes A1, A2 and A3. In this manner, the flexible implant 300, via the flexible section 310 can “self balance” or settle into or reach an equilibrium fit or best fit in the interbody disc space after implant 300 insertion. The flexible section 310 permits the implant 300 to reach a fit or equilibrium fit after implant insertion through motion and/or micro motion and flexibility of the flexible section 310 until the flexible implant 300 settles into the best anatomic fit in the disc space. This aspect of the flexible implant 300 enhances the biomechanical properties of the implant 300 while the vertebral fusion is setting. This novel aspect discussed with respect to
The flexible implant 800 of
The flexible implant assembly has a flexible section comprised of the leading end 805 pivotally connected to the trailing end 810 at a first hinge 812 to thereby permit rotational motion between the leading end 805 relative to the trailing end 810. The leading end 805 has a physical configuration adapted to facilitate or ease insertion of the flexible implant 800 into a disc space. In this aspect, the leading end 805 has a wedge shape nose 803. The wedge shaped nose 803 can impart a distracting force to adjacent vertebrae as the flexible implant 800 travels or is inserted into the disc space. The leading end 805 is pivotally connected to the trailing end 810 to form a hinged multi-piece flexible implant 800 shown in
The flexible spinal implant 800 further comprises an interior implant aperture 850 defined and formed by the pivotally connected leading end 805 and trailing end 810. The interior implant aperture 850 can be filled or packed with graft material before or after insertion of the flexible implant 800 into the selected disc space. The trailing end 810 also comprises an implant grip or attachment aperture 835 situated at the proximal implant end 837 which enables the coupling of an instrument (not shown) to the flexible spinal implant 800. The attachment aperture 835 would enable an instrument to couple to the flexible spinal implant 800 and deliver the flexible implant 800 through an implant insertion channel (not shown) into a selected disc space via a lateral approach.
The flexible implant 900 of
The flexible implant assembly 900 has a flexible section comprised of the leading end 905 pivotally connected to the trailing end 910 at a first hinge 912 to thereby permit rotational motion between the leading end 905 relative to the trailing end 910. The leading end 905 has a physical configuration adapted to facilitate or ease insertion of the flexible implant 900 into a disc space. In this aspect, the leading end 905 has a rounded shape nose 903. The rounded nose 903 can impart a distracting force to adjacent vertebrae as the flexible implant 900 travels or is inserted into the disc space. The leading end 905 is pivotally connected to the trailing end 910 to form a hinged multi-piece flexible implant 900, as shown in
The flexible spinal implant 900 further comprises an interior implant aperture 950 defined and formed by the pivotally connected leading end 905, first lateral side wall 906, opposite second lateral side wall 907 and trailing end 910. The interior implant aperture 950 can be filled or packed with graft material before or after insertion of the flexible implant 900 into the selected disc space. The trailing end 910 also comprises an implant grip or attachment aperture 935 situated at the proximal implant end 937 which enables the coupling of an instrument (not shown) to the flexible spinal implant 900. The attachment aperture 935 would enable an instrument to couple to the flexile spinal implant 900 and deliver the flexible implant 900 through an implant insertion channel (not shown) into a selected disc space via a lateral approach.
A front to back,
The novel aspect to correct or alleviate sagittal and/or coronal spinal deformities discussed with respect to
The flexible implant 1000 is preferably inserted into the disc space in a straight or substantially straight orientation, as discussed previously with reference to
The locking mechanism 1050 comprises a locking member 1025, a leading end locking passage 1015, a trailing end locking passage 1020, and at least one pair of adjacently and opposed hinge surfaces between the leading end 1005 and trailing end 1010. The locking mechanism 1050 may be engaged when the leading end locking passage 1015 and trailing end locking passage 1020 are sufficiently and substantially aligned when the implant is inserted into the disc space and the implant has a substantially straight orientation within the disc space. The locking member 1025 is then delivered via an instrument (not shown) and positioned at least partially inside both of the aligned leading end locking passage 1015 and trailing end locking passage 1020, and positioned to span across at least one pair of complimentary hinge surfaces in the implant's flexible section. The locking member 1025 may be delivered and inserted via at least one locking passage 1015 and 1020 complimentary pair. The locking passages 1015 and 1020 must come in complimentary locking passage pairs 1015 so that a locking member 1025 is able to span across the corresponding pair of complimentary hinge surfaces in the implant's flexible section when the locking passages 1015 and 1020 are substantially aligned in order to engage the locking mechanism 1050. Those of skill in the art will recognize that more than one complimentary pair of locking passages may be used in an implant. For example, to increase the locking stability and locking redundancy in any one flexible implant depending on the needs or requirements of patient anatomy, a physician or clinical need. The complimentary pair of locking passages is preferably oriented and positioned in the flexible implant flexible section such that when the locking mechanism is engaged, the flexible implant will no longer be flexible, pivotable or moveable within the disc space. The complimentary pair of locking passages 1015 and 1020 can be oriented and positioned concentrically or adjacently to an implant attachment aperture 145 of the flexible implant 1000, or other orientations and positions which permit the flexible implant 100 to be placed in a locking engagement.
In
In another embodiment, the locking mechanism 1050 may have a longer length such that it can simultaneously span across both paired hinge surfaces of the implant's flexible section, i.e., the first and third hinge surfaces 1003 & 1013 and the second and fourth hinge surfaces 1007 and 1017. Those of skill in the art will recognize that the locking mechanism 1050 contemplated herein will have a locking member 10025 which is positioned to span across a sufficient number of pairs of complimentary hinge surfaces of the implant's flexible section to lock the flexible implant 1000 in a straight or substantially straight orientation within the disc space. The locking mechanism 1025 may also comprise more than one set of locking member 1025 and locking passages 1015 and 1020 depending on the surgeon's preference or need, or the requirements or needs of the medical procedure. For example, in the case of the flexible implant 100 shown in
In some cases, it may be desirable to only partial lock the flexible implant. In such a case, the locking member may be positioned to span across paired hinge surfaces of the implant's flexible section which are less than the corresponding pivoting connections resulting in not all hinged surfaces being obstructed by the locking member, thereby leaving the flexible implant partially locked and partially moveable. For example in the flexible implant 100 shown in
The locking member 1025, the leading end locking passage 1015 and the trailing end locking passage 1020 preferably have complimentary configurations so that the locking member 25 can be delivered and inserted into the aligned leading end locking passage 1015 and trailing end locking passage 1020 to engage the locking mechanism 1050. As noted above, the leading end locking channel 1015 and the trailing end locking channel 1020 may be located concentrically or adjacent to an implant attachment aperture 145 to permit the locking member 1025 to be delivered once the spinal implant has been delivered and inserted in place. The locking member 1025 will cooperate with at least one pair of complimentary leading end locking channel 1015 and trailing end locking channel 1020 to permit the locking mechanism to be engaged.
The locking member 1025 is preferably configured and sized so as to be capable of being delivered through the same implant insertion channel that is used to deliver the flexible implant. For example, similar to an implant insertion channel 167 like that disclosed in
The locking member 1025 may be sized to enable it to be delivered and positioned in the flexible implant in a locking position or locking engagement position. The locking member 1025 may be sized such that it will firmly engage the leading end locking passage 1015 and trailing end locking passage 1020 via a friction fit or interference fit in its final locking position. Those of skill in the art will recognize that the locking member 1025 may have other shapes, size, length or configurations such that it can travel in the leading end locking passage 1015 and trailing end locking passage 1020 and also be held via a friction fit or interference fit in the leading end locking passage 1015 and trailing end locking passage 1020. The locking member 1025 may also be configured to firmly engage the leading end locking passage 1015 and trailing end locking passage 1020 via other securing mechanisms, for example, via a snap fit.
The locking member 1025 may be manufactured to have desired or needed characteristics or properties which enable it to be delivered and positioned in the flexible implant in a locking position or locking engagement position. The locking member 1025 should be of sufficient length to, when inserted in the locking passages, span across at least one pair of hinge surfaces of an implant's flexible section which correspond to pivoting connections to prevent and obstruct any further hinge movement and lock the flexible implant 1000 in a substantially straight orientation within the disc space. The locking member should also be manufactured with physical properties where it is sufficiently strong enough to perform the locking function without shearing or breaking once it is positioned in the locking passages 1015 and 1025.
The locking member 1025 may also have physical properties and characteristics which permit it to travel and traverse the implant delivery path and implant delivery components, such as an insertion channel. In a preferred embodiment, the locking member 1025 is manufactured to have characteristics or properties which permit it to travel and traverse the implant delivery path and the implant insertion channel used to deliver the flexible implant, such as the implant insertion channel 167 disclosed in
During locking member 1025 delivery, the locking member 1025 would travel inside an implant insertion channel similar to insertion channel 160 to reach the desired or selected disc space level. In order for the locking member 1025 to reach and enter the disc space in a substantially straight lateral approach orientation, the locking member 1025 will be guided, by an instrument (not shown) to travel through the interior walls of the implant insertion channel. The locking member 1025 will reach and have to traverse a channel turn section similar to the channel turn section 164 of
In some instances, the locking member 1025 may also have physical properties which permit it to flex, deflect, bend or deform as it travels and traverses the bend or corner of an implant insertion channel on its way to the implant locking passages 1015 and 1020. For example, in a case of a flexible implant with many pivoting or movable hinges at its implant flexible section, it may be desirable to have a locking member 1025 that is longer in length and that thus may not be able to traverse the insertion channel turn section due to its length. In such an instance, the locking member 1025 will have physical properties and characteristics which permit it to flex, deflect, bend or deform sufficiently and as needed to enable the locking member 1025 to traverse the insertion channel turn section. In particular, locking member 1025 would be manufactured such that it can flex, deflect, bend or deform sufficiently to enable it to travel and traverse through and around the channel turn section of the insertion channel and into the implant's aligned locking passages 1015 and 1020.
During delivery of such a bending or deforming locking member 1025, the locking member 1025 would travel inside the implant insertion channel to reach the selected disc space level. In order for the locking member 1025 to reach and enter the disc space in a substantially straight lateral approach orientation, the locking member 1025 will be guided by the interior walls of the implant insertion channel 1160. The deforming locking member 1025 will reach and have to traverse a channel turn section. The channel turn section will interact with and force the locking member 1025 to flex, deflect, bend or deform while traveling through the channel turn section. This cannel turn section interaction imparts a force to deform the locking member 1025 such that the locking member 1025 flexes, deflects, bends or deforms to thereby enable travel of the locking member 1025 through the channel turn section 1164. In this manner, the locking member 1025 is adapted to flex, deflect, bend or deform and turn from its delivery path and enter the disc space in a substantially straight lateral approach orientation. The forced flexing, deflection, bending or deforming by the channel turn section interaction transitions and assists the locking member 1025 to travel and traverse through the channel turn section of the insertion channel and into the implant's aligned locking passages 1015 and 1020.
The locking member 1025 and corresponding locking passages may also be manufactured to have a desired or needed configurations which enables it to be delivered and positioned in the flexible implant in a locking position or locking engagement position. In one embodiment, shown in
Those of skill in the art will recognize that other complimentary shapes, size and configurations may be used for the locking member 1025, the leading end locking passage 1015 and the trailing end locking passage 1020 so long as these components have complimentary configurations that permit the locking member 1025 to be inserted into and to traverse the leading end locking passage 1015 and trailing end locking passage 1020 to reach a locking position. For example, in one case, the locking member 1025, leading end locking passage 1015 and trailing end locking passage 1020 may have complimentary T-configurations. In this case, the leading end locking passage 1015 and trailing end locking passage 1020 would have a T-shaped passage cross-section and the locking member 1025 would have a complimentary T-shaped rail cross-section which can be inserted and can travel therein.
A flexible implant with an engagable locking mechanism discussed with respect to
In a further aspect contemplated for the flexible implants depicted and discussed with respect to
The flexible implants and locking member disclosed in this disclosure are preferably comprised of biocompatible materials substrates which can be attached to the novel flexible implant sections to form a whole flexible spinal implant or locking member. The biocompatible material substrate may include, among others, polyetheretherketone (PEEK) polymer material, homopolymers, co-polymers and oligomers of polyhydroxy acids, polyesters, polyorthoesters, polyanhydrides, polydioxanone, polydioxanediones, polyesteramides, polyaminoacids, polyamides, polycarbonates, polylactide, polyglycolide, tyrosine-derived polycarbonate, polyanhydride, polyorthoester, polyphosphazene, polyethylene, polyester, polyvinyl alcohol, polyacrylonitrile, polyamide, polytetrafluorethylene, poly-paraphenylene terephthalamide, polyetherketoneketone (PEKK); polyaryletherketones (PAEK), cellulose, carbon fiber reinforced composite, and mixtures thereof. The biocompatible material substrate may also be a metallic material and may include, among others, stainless steel, titanium, nitinol, platinum, tungsten, silver, palladium, cobalt chrome alloys, shape memory nitinol and mixtures thereof. The biocompatible material used can depend on the patient's need and physician requirements.
While embodiments of the invention have been illustrated and described in detail in the present disclosure, the disclosure is to be considered as illustrative and not restrictive in character. All changes and modifications that come within the spirit of the invention are desired to be protected and are to be considered within the scope of the disclosure.
This application is a continuation-in-part of U.S. patent application Ser. No. 12/533,877 filed on Jul. 31, 2009, which is incorporated herein by reference in its entirety.
Number | Date | Country | |
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Parent | 12533877 | Jul 2009 | US |
Child | 12605145 | US |