Patent Application
20230346425
The exemplary embodiments of present invention relate generally to a spinal fusion instruments and techniques and, more specifically, to a spinal fusion instrumentation system and methods of using a spinal fusion instrumentation system for performing a minimally invasive spinal fusion.
Traditional spinal fusions typically involve a large open dissection with pedicle screw fixation. This technique is associated with muscle damage, risk of infection, extended surgical times, long hospital stays and possible injury to sensitive neural elements. Recently, there has been an increasing emphasis in spinal surgery for muscle-sparing procedures that utilize sophisticated techniques/instruments to achieve the goals of surgery in a minimally invasive manner and assist with rapid recovery from surgery that addresses risks associated with traditional spinal fusions.
In accordance with an exemplary embodiment there is provided a surgical instrument kit comprising a curved trocar, a flexible cannula for positioning over the curved trocar, a flexible rasp device, and a bone graft delivery container.
According to an aspect, the curved trocar is used to penetrate the skin and pass between vertebral bony elements to be fused. According to a further aspect, the curved trocar comprises a plurality of curved trocars each having a differing radius of curvature for optimum insertion and positioning of the trocars between adjacent vertebrae of persons of various sizes. According to a further aspect, the curved trocar includes a radius of curvature of about 2 mm to 1000 mm. According to a further aspect, the curved trocar includes a radius of curvature of about 2 mm to 500 mm. According to a further aspect, the curved trocar includes a straight proximal portion, a curved portion extending from the straight proximal portion, and a straight distal portion extending from the curved portion. According to a further aspect, a longitudinal axis of the straight distal portion is disposed at an angle of about 80°-175° relative to a longitudinal axis of the straight proximal portion. According to a further aspect, the straight proximal portion is about 10 mm to 150 mm in length. According to a further aspect, the straight distal portion is about 10 mm to 50 mm in length. According to a further aspect, the curved trocar has an overall diameter of about 2 mm and 10 mm.
According to an aspect, the flexible cannula includes a straight proximal portion, a curved portion extending from the straight portion, and a straight distal portion extending from the curved portion. According to a further aspect, the straight distal portion of the flexible cannula includes a tapered tip. According to a further aspect, the straight distal portion of the flexible cannula includes a notch. According to a further aspect, a longitudinal axis of the straight distal portion of the flexible cannula is disposed at an angle of about 80°-175° relative to a longitudinal axis of the straight proximal portion. According to a further aspect, the straight proximal portion is about 10 mm to 150 mm in length. According to a further aspect, the straight distal portion is about 10 mm to 50 mm in length. According to a further aspect, the flexible cannula comprises a plurality of flexible cannulas each having successively increasing outer diameters and successively decreasing lengths, respectively, which generally maintain their shape in situ. According to a further aspect, the plurality of flexible cannulas each have an overall diameter ranging from about 4 mm to 25 mm. According to a further aspect, the plurality of flexible cannulas each have a wall thickness of about 1 mm to 2 mm.
According to an aspect, the flexible rasp device comprises a flexible shaft connected to a rasp sized to pass through the flexible cannula. According to a further aspect, the flexible rasp device include rasps of multiple lengths, sizes and cutting grades for decortication of vertebral features such as vertebral bony elements. According to a further aspect, the flexible rasp device may be manipulated by hand or driven by a tool, e.g., a drill, in order to decorticate vertebral features.
According to an aspect, the surgical instrument kit further comprises a cannula guide configured for insertion into the flexible cannula. According to a further aspect, the cannula guide comprises a plurality of cannula guides each having successively increasing outer diameters. According to a further aspect, each of the plurality of cannula guides have a straight proximal portion and a curved distal portion.
According to an aspect, the surgical instrument kit further comprises a flexible plunger for pushing or moving the bone graft delivery container through the flexible cannula, wherein the bone graft delivery container comprises a resorbable, permeable vessel, such as a suture mesh bag, containing bone graft material, which remains in situ to promote spinal fusion.
The subject disclosure provides an instrumentation system and method for performing a percutaneous spinal fusion, in particular to effectuate reliable and robust fusion of the vertebrae using less invasive techniques than those known in the art. The system and method can also be used for other applications, e.g., as a stand-alone technique for spinal fusion, a technique for minimally invasive revision spinal fusion, or combined to augment fusion with other forms of minimally invasive spinal fusion surgeries such as an anterior lumbar interbody fusion, transforaminal lumbar interbody fusion and interspinous fusion.
In accordance with an exemplary embodiment, a series of instruments is used to percutaneously fuse adjacent vertebrae utilizing a minimally invasive surgical procedure. Steps of the procedure include: 1) inserting a curved trocar percutaneously into contact with vertebral bony elements of adjacent vertebrae including, but not limited to, the transverse processes; 2) sliding a flexible cannula over the curved trocar; 3) withdrawing the trocar from the flexible cannula, whereby the flexible cannula generally maintains its shape in situ; 4) inserting a flexible rasp through the flexible cannula until it protrudes from a notch at a distal end of the flexible cannula; 5) moving the rasp manually or by a drill to decorticate the vertebral bony elements of adjacent vertebrae; 6) removing the rasp from the flexible cannula; 7) inserting a bone graft delivery system bag containing bone graft material through the flexible cannula until it is discharged from the notch at the distal end of the flexible cannula for placement onto vertebral structures to be fused, e.g., adjacent vertebral bony elements; and 8) removing the flexible cannula from the patient.
In accordance with another exemplary embodiment, a series of instruments is used to percutaneously fuse adjacent vertebrae utilizing a minimally invasive surgical procedure. Steps of the procedure include: 1) inserting a curved trocar percutaneously into contact with vertebral bony elements of adjacent vertebrae including, but not limited to, the transverse processes; 2) sliding a first flexible cannula over the curved trocar; 3) withdrawing the trocar from the first flexible cannula, whereby the first flexible cannula generally maintains its shape in situ; 4) inserting a first cannula guide into the first flexible cannula; 5) sliding a second flexible cannula having an internal diameter larger than the outer diameters of the first cannula guide and first flexible cannula over the first cannula guide and the first flexible cannula, whereby the second flexible cannula generally maintains its shape in situ; 6) removing the first cannula guide and first flexible cannula from the second flexible cannula; 7) repeating steps 4 through 6 using second and subsequent cannula guides of increasing outer diameters and third and subsequent flexible cannulas of increasing inner diameters larger than the outer diameters of the second flexible cannula and the second and subsequent cannula guides; 8) inserting a flexible rasp through a last-placed flexible cannula until it protrudes from a notch at a distal end of the last placed flexible cannula; 9) moving the rasp manually or by a drill to decorticate the vertebral bony elements of adjacent vertebrae; 10) removing the rasp from the last-placed flexible cannula; 11) inserting a bone graft delivery system bag containing bone graft material through the last-placed flexible cannula until it is discharged from the notch at the distal end of the last placed flexible cannula for placement onto vertebral structures to be fused, e.g., adjacent vertebral bony elements; and 12) removing the last-placed flexible cannula from the patient. The present spinal fusion instrumentation system is designed to ensure ease of use and allows for a rapid surgical procedure to create a spinal fusion thus saving operating room time.
The exemplary embodiments of the present disclosure provide a series of instruments that allow for creation of a fusion bed between transverse processes without wide surgical dissection.
Other features and advantages of the subject disclosure will be apparent from the following more detail description of the exemplary embodiments.
The foregoing summary, as well as the following detailed description of the exemplary embodiments of the subject disclosure, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the present disclosure, there are shown in the drawings exemplary embodiments. It should be understood, however, that the subject application is not limited to the precise arrangements and instrumentalities shown.
Reference will now be made in detail to the various exemplary embodiments of the subject disclosure illustrated in the accompanying drawings. Wherever possible, the same or like reference numbers will be used throughout the drawings to refer to the same or like features. It should be noted that the drawings are in simplified form and are not drawn to precise scale. Certain terminology is used in the following description for convenience only and is not limiting. Directional terms such as top, bottom, left, right, above, below and diagonal, are used with respect to the accompanying drawings. The term “distal” shall mean away from the center of a body. The term “proximal” shall mean closer towards the center of a body and/or away from the “distal” end. The words “inwardly” and “outwardly” refer to directions toward and away from, respectively, the geometric center of the identified element and designated parts thereof. Such directional terms used in conjunction with the following description of the drawings should not be construed to limit the scope of the subject application in any manner not explicitly set forth. Additionally, the term “a,” as used in the specification, means “at least one.” The terminology includes the words above specifically mentioned, derivatives thereof, and words of similar import.
“About” as used herein when referring to a measurable value such as an amount, a temporal duration, and the like, is meant to encompass variations of ±20%, ±10%, ±5%, ±1%, or ±0.1% from the specified value, as such variations are appropriate.
“Substantially” as used herein shall mean considerable in extent, largely but not wholly that which is specified, or an appropriate variation therefrom as is acceptable within the field of art. “Exemplary” as used herein shall mean serving as an example.
Throughout the subject application, various aspects thereof can be presented in a range format. It should be understood that the description in range format is merely for convenience and brevity and should not be construed as an inflexible limitation on the scope of the subject disclosure. Accordingly, the description of a range should be considered to have specifically disclosed all the possible subranges as well as individual numerical values within that range. For example, description of a range such as from 1 to 6 should be considered to have specifically disclosed subranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6 etc., as well as individual numbers within that range, for example, 1, 2, 2.7, 3, 4, 5, 5.3, and 6. This applies regardless of the breadth of the range.
Furthermore, the described features, advantages and characteristics of the exemplary embodiments of the subject disclosure may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize, in light of the description herein, that the subject disclosure can be practiced without one or more of the specific features or advantages of a particular exemplary embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all exemplary embodiments of the present disclosure.
In accordance with an exemplary embodiment of the subject disclosure there is provided a surgical instrument kit for performing a spinal fusion. The surgical instrument kit comprises a curved trocar 10, a flexible cannula 30 for positioning over the curved trocar, a flexible rasp device 70, and a bone graft delivery container 90, each of which are described below. The surgical instrument kit may additionally include at least one cannula guide 50 for placement of successively larger flexible cannulas, a plunger 80 for moving the bone graft delivery container within the flexible cannula, and flexible guide wires 100a, 100b for contacting vertebral structure and facilitating selection of an appropriate curved trocar.
Referring now to the drawings,
According to a further aspect, the surgical instrument kit comprises a plurality of curved trocars each having a differing radius of curvature and/or differing lengths of the straight proximal portion and/or differing lengths of the straight distal portion. Similarly, the dimensions of the straight proximal portion, the straight distal portion and the curved portion of the trocars may be varied in order to be particularly adapted for patient-specific applications based on patients' unique spinal physiologies.
By way of example, but not limitation, an exemplary surgical instrument kit in accordance with the present disclosure may include from about 1 to 24 trocars of varying sizes, shapes and curvatures to accommodate patients spanning at least the 5th to 95th percentile of the height, weight or other physiological parameters of patients likely to undergo a surgical procedure as described herein.
A longitudinal axis “A” of the straight distal portion 16 of the curved trocar 10 is disposed at an angle α of about 90°-175° relative to a longitudinal axis “B” of the straight proximal portion 12, but can alternatively be about 80, 100, 110, 120, 130, 140, 150, 160, and 170 degrees.
The curved trocar 10 may be formed from any suitable rigid material including metal, e.g., stainless steel, or a rigid polymer.
The curved trocar has an overall diameter of about 2 mm to 10 mm, and preferably about 2 mm to 5 mm, but can alternatively have an overall diameter of about 1, 3, 4, 6, 7, 8, 9, 11 and 12 mm. The distal end of the trocar has a sharpened tip 18 to facilitate passage of the curved trocar through skin, muscle and other bodily tissue. Additionally, the proximal end of the straight proximal portion may include an unillustrated fixed or removable handle to facilitate percutaneous manipulation of the straight distal portion of the trocar adjacent vertebral bony elements of spinal vertebrae.
Referring to
The flexible cannulas 30 and 30′, as well as flexible cannulas 30a-30d described below, can be curved or bent as described above, or straight. Additionally, they can be formed from any suitable flexible material including, without limitation, Nitinol or a flexible polymer. The flexible cannulas are structured to generally maintain a bent shape in situ, e.g., their original predefined curvature. In addition, the flexible cannulas can have markings 44 along their length to identify the depth of insertion of the cannulas, including when the cannulas are fully inserted in a patient. Moreover, the flexible cannulas can be provided with radiopaque markers 45 e.g., and, without limitation, at their distal ends for enhanced visibility when the surgical procedure is performed under intraoperative fluoroscopy.
As shown in
Returning to
Referring first to
The user selects the size and curvature of the curved trocar based on examination of pre-operative imaging. This determines the alignment of the transverse processes between adjacent vertebrae to select the appropriate radius of curvature. Similarly, by examining the depth of the transverse process in relation to the skin surface, a user can select the size of the straight proximal portion 12 (
The next step of the surgical procedure is shown in
With the first cannula guide 50a inserted into the first flexible cannula 30a, the next step in the procedure is to position a second flexible cannula 30b (
The next step of the surgical procedure is shown in
With the second cannula guide 50b inserted into the second flexible cannula 30b, the next step in the procedure is to position a third flexible cannula 30c, which may have an internal diameter of, e.g., 16 mm, over the straight proximal portions of the second cannula guide and the second flexible cannula, as shown in
The next step of the surgical procedure is shown in
With the third cannula guide 50c inserted into the third flexible cannula 30c, the next step in the procedure is to position a fourth flexible cannula 30d, which may have an internal diameter of, e.g., 20 mm, over the straight proximal portions of the third cannula guide and the third flexible cannula, as shown in
As shown in
The foregoing surgical procedure can be summarized as follows. A series of instruments is used to percutaneously fuse adjacent vertebrae utilizing a minimally invasive surgical procedure. Steps of the surgical procedure include: 1) inserting a curved trocar percutaneously into contact with vertebral bony elements of adjacent vertebrae including, but not limited to, the transverse processes; 2) sliding a first flexible cannula over the curved trocar; 3) withdrawing the trocar from the first flexible cannula, whereby the first flexible cannula generally maintains its shape in situ; 4) inserting a first cannula guide into the first flexible cannula; 5) sliding a second flexible cannula having an internal diameter larger than the outer diameters of the first cannula guide and first flexible cannula over the first cannula guide and the first flexible cannula until the distal end of the second flexible cannula is adjacent the distal end of the first flexible cannula, whereby the second flexible cannula generally maintains its shape in situ; 6) removing the first cannula guide and first flexible cannula from the second flexible cannula; 7) repeating steps 4 through 6 using second and subsequent cannula guides of increasing outer diameters and third and subsequent flexible cannulas of increasing inner diameters larger than the outer diameters of the second flexible cannula and the second and subsequent cannula guides; 8) inserting a flexible rasp through a last-placed flexible cannula until it protrudes from a notch at a distal end of the last placed flexible cannula; 9) moving the rasp manually or by a drill to decorticate the vertebral bony elements of adjacent vertebrae; 10) removing the rasp from the last-placed flexible cannula; 11) inserting a bone graft delivery system bag containing bone graft material through the last-placed flexible cannula until it is discharged from the notch at the distal end of the last-placed flexible cannula for placement onto vertebral structures to be fused, e.g., adjacent vertebral bony elements; and 12) removing the last-placed flexible cannula from the patient.
In this procedure, selection of appropriate flexible cannulas of increasing diameters is based on the alignment of the guide wires on the vertebral bony elements. In particular, a distance “L” between the guide wires establishes a corresponding length “L” of the straight distal portions of the flexible cannulas 30 (only one of which is shown in
The surgical procedure shown in
According to a further embodiment, another surgical procedure according to the subject disclosure is provided. According to this exemplary embodiment, a directable guide wire having a curved tip arises from a cannulated needle placed on a vertebral bony element of, for example, the L5 vertebrae. The curved guide wire is then rotated to move the curved tip superior/inferior/medial/lateral based on where a bony element of an adjacent vertebrae, e.g., the L4 vertebrae, appears on fluoroscopic images. Once the tip of the curved guide wire is positioned on the bony element of the adjacent vertebrae, increasingly larger diameter flexible cannulas are placed over the guide wire, the guide wire is then removed, the bony elements can be decorticated and the bone graft delivery system bag placed at the grafting site in a manner similar to
Another surgical procedure according to the subject disclosure includes the facet joint being grafted. According to this exemplary procedure, a surgical instrument kit is first obtained that includes a bovie tool, for example as disclosed in U.S. Pat. No. 10,064,675, the entire disclosure of which is hereby incorporated by reference, in addition to certain other elements common to the previously described surgical instrument kits. According to this procedure, a guide wire is first dropped into position on the facet joint of adjacent vertebrae and a 0.5 cm to 1.0 cm incision is made in the patient's skin. A series of increasingly larger diameter cannulas can be placed over the guide wire in order to dilate the soft tissue and minimize muscle injury. A bovie tool is dropped in the largest cannula and is used to bovie the facet joint. A rasp or burr is then used to decorticate the facet joint. A bone graft delivery system bag is then placed down the largest cannula and is packed with a bone tamp.
The surgical instrument kit of the subject disclosure results in several new and advantageous features relative to existing spinal fusion techniques. For example, trocars are specifically designed to closely approximate the trajectory between bony vertebral elements such as the transverse processes. There is also no large incision and associated dissection of bodily tissue. As a result, a bone graft and/or infusion may be placed at the posterolateral gutter without a large incision, and there is no large exposure of bony elements e.g., transverse processes during decortication.
Further, the subject surgical instrumentation kit has use in conjunction with other technology and clinical applications. For instance, the subject surgical instrument kit can be used in association with a Wiltse fusion technique with interspinous plates, as well as pedicle screws without interbody, cortical screws, and the like, in order to perform Wiltse fusion more quickly and less invasively. In addition, it can be used to back up Anterior Cervical Discectomy and Fusion (ACDF) and Anterior Lumbar Interbody Fusion (ALIF). That is, the methods of using the surgical instrument kit reduce concerns regarding pseudarthrosis as the exemplary embodiments result in a quick, minimally invasive manner to further add stability to the construct. The subject surgical instrument kit is also useful with Lateral Lumbar Interbody Fusion (LLIF) and provides increased stability. In particular, rather than using percutaneous screws, the surgical instrument kit and its methods of use create a percutaneous posterolateral fusion bed that can augment support of an interbody in place. Additionally, the surgical instrument kit is adaptable for use with interspinous plates, cortical screws and facet screws produced by surgical instrumentation manufacturers to augment fusion.
While described in connection with in-situ fusion of posterior aspects of the lumbar spine, it is to be understood that the instruments and system disclosed herein may find equal beneficial effect in fusing posterior aspects of the cervical and thoracic spines as well. Further, the percutaneous method disclosed herein may be used to augment bony healing for bone fractures (e.g., femur, humerus, tibia, etc.).
It will be appreciated by those skilled in the art that changes could be made to the exemplary embodiments described above without departing from the broad inventive concept thereof. It is to be understood, therefore, that this disclosure is not limited to the particular exemplary embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the claims defined herein.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2020/057984 | 10/29/2020 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 62928034 | Oct 2019 | US |
