Patent Application
20160007994
The present disclosure generally relates to orthopaedic surgery, and more specifically, to an apparatus and procedure for advancing soft tissue into a bony tunnel.
When soft tissue such as tendons or ligaments becomes detached from bone, joints may be rendered non-functional. For example, tendon detachment may cause potential motor deficits and weakness, while ligament detachment may cause instabilities. In order to restore optimal functionality, soft tissue must be reattached to bone. Thus, a variety of different devices and procedures have been developed for reattaching soft tissue to bone.
The disclosed subject matter relates to an apparatus for affixing soft tissue to bone. The apparatus comprises a first arm including a first jaw on a distal end of the first arm, and a second arm mated to the first arm at a hinge. The second arm also includes a second jaw on a distal end of the second arm. The hinge is located between the proximal ends of the first and second arms and distal ends of the first and second arms. To enter into an engaged position, the first and second arms pivot around the hinge such that the distal ends of the first and second arms close towards one another, and the proximal ends of the first and second arms move apart from one another. The engaged position causes the first jaw on the distal end of the first arm and the second jaw on the distal end of the second arm to compress and hold soft tissue.
According to various aspects of the subject technology, a system for affixing soft tissue to bone is provided. The system includes a clamp and an applicator. The clamp includes a first arm comprising a first jaw on a distal end of the first arm, a threaded socket for insertion of a screw, and a set of mating grooves on a proximal end of the first arm. The clamp further includes a second arm mated to the first arm at a hinge. The second arm comprises a second jaw on a distal end of the second arm. The hinge is located between the proximal ends of the first and second arms and distal ends of the first and second arms. When the screw is advanced into the threaded socket, a pressure is applied by the screw onto a lever in the second arm causing the first arm and second arm to progressively pivot around the hinge and advance to an engaged position where the distal ends of the first and second arms close towards one another and the proximal ends of the first and second arms move apart from one another. The system further includes a driver. The driver comprises a knob operable by a user and a driver shaft attached to the knob. The driver shaft provides for an application, by the user, of a torque from the driver to the screw insertable into the threaded socket. The system also includes an applicator comprising a proximal handle and a cannulated shaft connected to the handle on the proximal end of the cannulated shaft. The cannulated shaft includes a tip configured to mate to the first arm by attaching to the set of mating grooves on the proximal end of the first arm. The cannulated shaft further includes a cannulation through which the driver passes.
The disclosed subject matter also relates to a method for affixing soft tissue to bone. The method comprises inserting a clamp and the soft tissue into an aperture in the surface of a bone structure, where the soft tissue is interposed between the clamp. The clamp includes a first arm comprising a first jaw on a distal end of the first arm and a threaded socket for insertion of a screw. The clamp further includes a second arm mated to the first arm at a hinge. The second arm comprises a second jaw on a distal end of the second arm. The hinge is located between the proximal ends of the first and second arms and distal ends of the first and second arms. When the screw is advanced into the threaded socket, a pressure is applied by the screw onto a lever in the second arm causing the first arm and second arm to progressively pivot around the hinge and advance to an engaged position where the distal ends of the first and second arms close towards one another and the proximal ends of the first and second arms move apart from one another. The method further comprises advancing a screw, with a driver, into the threaded socket to cause the clamp to transition to the engaged position. The first jaw on the distal end of the first arm and the second jaw on the distal end of the second arm progressively compress and hold the soft tissue when the clamp is transitioned to the engaged position.
It is understood that other configurations of the subject technology will become readily apparent to those skilled in the art from the following detailed description, wherein various configurations of the subject technology are shown and described by way of illustration. As will be realized, the subject technology is capable of other and different configurations and its several details are capable of modification in various other respects, all without departing from the scope of the subject technology. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not as restrictive.
Certain features of the subject technology are set forth in the appended claims. However, for purpose of explanation, several embodiments of the subject technology are set forth in the following figures.
The detailed description set forth below is intended as a description of various configurations of the subject technology and is not intended to represent the only configurations in which the subject technology may be practiced. The appended drawings are incorporated herein and constitute a part of the detailed description. This description includes specific details for the purpose of providing a thorough understanding of the subject technology. However, the subject technology is not limited to the specific details set forth herein and may be practiced without these specific details.
The disclosed subject matter relates to an apparatus for affixing soft tissue to bone. The apparatus comprises a first arm including a first jaw on a distal end of the first arm, and a second arm mated to the first arm at a hinge. The second arm also includes a second jaw on a distal end of the second arm. The hinge is located between the proximal ends of the first and second arms and distal ends of the first and second arms. To enter into an engaged position, the first and second arms pivot around the hinge such that the distal ends of the first and second arms close towards one another, and the proximal ends of the first and second arms move apart from one another. The engaged position causes the first jaw on the distal end of the first arm and the second jaw on the distal end of the second arm to compress and hold soft tissue.
There are at least two types of bony sockets or tunnels to which soft tissue may be affixed, the first being a circumferential bone with a certain density, and the second being relatively hollow bone. A socket has only one aperture and a tunnel has two apertures, one at each end of the tunnel. While both types of sockets or tunnels have a surface cortical bone, circumferential bone has deeper metaphyseal bone with varying degrees of density. Cortical bone is the hardest, densest bone, and is the optimal bone for achieving implant fixation. Thus, a soft tissue fixation device that relies on cortical bone would be considered relatively ideal. There is also a preference for advancing soft tissue into bone without externalizing the soft tissue when certain soft tissue is involved. For example, externalizing soft tissue such as the proximal biceps tendon in the human shoulder requires potentially more dissection and surgical time, both of which should be minimized if possible so as to reduce post-surgical pain and intra-operative risks (e.g. anesthesia risks).
The currently disclosed soft tissue fixation device fixates soft tissue directly, then allows for fixation through a bony hole or aperture that leads into a tunnel, socket, or void. Thus, the device does not primarily rely on interference fixation alone (e.g. with a screw, or similar implant that fills a bony tunnel with soft tissue interposed between the implant and bone, metaphyseal and or cortical). The claimed device, however, does not preclude subsequent fixation that relies on interference or other manners of fixation. For example, it the device were to be placed entirely below the cortical bone, a standard interference screw could still be advanced over the device, with the soft tissue of interest achieving interference fixation between the screw and any adjacent bone.
The device described herein provides for direct soft tissue fixation (as the device itself fixates to soft tissue) and subsequent bony fixation (as the device engages bone) using the features of the described device and applicator with driver, as described in detail below. The device also provides for fixation in all types of bone, hollow or otherwise, and in two ways, open and arthroscopic. Notably, while there may exist implants that primarily, and in some cases solely, rely on interference fixation of soft tissue between two surfaces, implant and bone (versus direct fixation between implant and soft tissue), the device described herein relies also on interference fixation insofar as the device provides frictional resistance of any soft tissue of interest between the device and adjacent bone.
While the hinge may take on any one of multiple configurations to enable a hinge mechanism, a hinge that limits the material for the device would be relatively ideal from a mechanical standpoint so as to limit the number of material and mechanical interfaces exposed to potential failure. For example, a hinge between the first and second arms could be created without additional material beyond a simple mating between the first and second arms. For example, the first arm could slide into a matable slot of the second arm in a direction that is orthogonal to the long axis of the device, or as another example the hinge could be configured to snap together.
In order to enter into an engaged position, the first arm 105 and second arm 115 pivot around the hinge 120 such that the distal ends of the first and second arms close towards one another. At the same time, the proximal ends of the first arm and second arm move apart from one another. By advancing into an engaged position, the first jaw on the distal end of the first arm and the second jaw on the distal end of the second arm can compress and hold soft tissue, as will be shown in
In some embodiments, each of the first and second arms may include a set of channels 140. The channels provide a passage for durable sutures 145. When the suture passing through the channels is cinched with a certain tension, the soft tissue fixation device can be transitioned to an engaged position. And when the free ends are tied off to one another, the soft tissue fixation device can be held and maintained in an engaged position, with the soft tissue of interest interposed between the first and second arms. The suture that passes through the channels, and between each of the two arms, should be distal to the hinge center of rotation to initiate the movement of the arms to an engaged position. This does not preclude the creation of other channels within the device at any location relative to the hinge, proximal or distal. Sutures passing through the device through channels can be used for fixation of additional soft tissue after the device is secured to its intended location within bone. Additionally, in some embodiments, at least one of the first jaw and the second jaw may include a set of horizontal teeth and/or a set of vertical teeth 150, that may or may not interdigitate. The teeth provide extra grip to the first and second jaws, thereby providing a more secure hold on the soft tissue interposed between the first and second arms. The teeth effectively increase the contact area between the soft tissue of interest and the first and second jaws, increasing the frictional resistance to soft tissue slippage and failure when a stress or load is applied. These teeth 150 or protrusions may take any number of cross-sectional geometries and configurations (e.g. beveled, serrated, needle-like, tapered) in order to optimize contact with the soft tissue of interest.
Further increasing the contact area between soft tissue and the implantable soft tissue fixation device are additional teeth or ridges 160 at the proximal end of the first arm 105. These additional teeth or ridges 160 provide frictional resistance between the soft tissue fixation device and any soft tissue of interest when the device is inserted through an aperture in cortical bone, as will be described in further details in FIGS. 3 and 5A-5C. The soft tissue of interest will experience interference fixation between the device and adjacent bone. Notably, a ridge, or any number of ridges, may be disposed circumferentially about the entire proximal aspect of the device (not depicted). A ridge or ridges on the device, orthogonal to the ridges 160 depicted (on the sides of the device where ridges 160 are not depicted), could serve to engage cortical bone should the operator choose not to place the device completely beneath the cortical bone. With the proximal aspect of the device (proximal to the hinge center of rotation) flush to the surface of the cortical bone or proud, the ridge or ridges (not depicted) could be configured to increase contact with the adjacent bone once the device is in the engaged position, thereby increasing the resistance to device pull-out failure from the bone. A ridge is not necessarily a protrusion of implant material, but in effect could also be made by creating cutout notches (using less material). The notch or notches could be configured to engage adjacent bone such that any device material proximal to the notch cutout could overhang the surface aperture cortical bone with a lip of device material. This might be one of many scenarios where the soft tissue fixation device is slightly proud in an engaged position relative to the surface cortical bone. One advantage of such a lip of device material that overhangs the surface cortical bone is that the device could be well maintained at a fixed depth within the socket or tunnel of interest. In other words, the lip would act as a mechanical stopper against device insertion beyond a certain depth.
In this figure, the first and second arm of the soft tissue fixation device is pivoted around the hinge into a fully engaged position. That is, the first jaw on the distal end of the first arm and the second jaw on the distal end of the second arm are in closer proximity to one another to compress and hold soft tissue (not shown) interposed between the first and second jaws. The teeth or ridges 150, 160 increase frictional resistance to soft tissue slippage, elongation, and failure by increasing contact area between the implantable soft tissue fixation device and the soft tissue of interest. Teeth 150 increase contact area between soft tissue and device, and help fixate soft tissue directly with the device in an engaged position, while ridges 160 increase contact area between soft tissue and implant to increase frictional resistance to pull-out failure of soft tissue interposed between the device and bone.
The soft tissue fixation device shown in
In an alternate embodiment, the screw may not be necessary to advance the device to the engaged position. For example, the driver itself could be threaded at its distal tip to function as a screw would, and as another example, a non-threaded tool or peg could be advanced into the socket in order to create a force against a lever, thus progressively causing the distal end of the first and second arms to close towards one another.
It is noted that when the soft tissue fixation device is in the fully engaged position, the first and second proximal ends 130 and 135 are more spread out than when the device is in the unengaged position. As will be shown in more detail in
Notably, the soft tissue fixation device may not need to be wholly on the underside of cortical bone. In other words, the device, prior to creating the engaged position, may be applied so that the proximal ends of the first and second arms (proximal to the hinge center of rotation) are contained within the cortical bone at the aperture of the bony tunnel or socket, flush or slightly proud relative to the surface of the cortical bone aperture. Once the proximal aspect of the device (that aspect proximal to the hinge center of rotation) is contained within the cortical bone, the screw may be advanced so that the proximal ends of the first and second arms spread out until contact is made with the cortical bone of the aperture, thus fixating the soft tissue of interest into a bony socket or tunnel. In this scenario, direct fixation to bone is created between the device and bone, and interference fixation is created as the soft tissue is held tightly between the device and adjacent bone. The interference fixation will be variable depending on the type of bone encountered. Metaphyseal (non-hollow bone) versus diaphyseal (relatively hollow bone) will provide variable fixation strengths. For both types of bone, interference fixation is provided by cortical bone.
In some embodiments, the first and second arms may include a set of channels 140 that provide a passage for durable sutures 145. The sutures, when passed through the channels, cinched, and tied off, provide an extra mechanism of securing the soft tissue fixation device in the engaged position beyond the screw element. As shown in
In some embodiments, an eyelet or hole cutout may be provided on the distal end of either of the two arms (not shown in
In some embodiments, the screw 210 and socket 205 may further be configured to engage extra sutures from another source. This may be accomplished by placing free ends or a looped end of the extra sutures through the socket 205 prior to inserting the device into bone. The extra sutures can be passed through the socket 205 in a distal to proximal direction, or a proximal to distal direction. Once the device is placed to the desired position within the bone the extra sutures may be variably tensioned. When the screw 210 is inserted and advanced into the socket 205, the sutures are securely fixed in place at the location of the aperture, fixated between the screw threads and the matable thread grooves of the socket.
The soft tissue fixation device in an unengaged position is first inserted through an aperture 310 in the cortical bone 305. When the device is in an unengaged position, the outer surface of the first arm is substantially parallel to an outer surface of the second arm, thereby providing a slimmer profile for which the device may pass through an aperture. In order for the soft tissue fixation device to operate properly, the aperture must be of a size large enough for the device to pass through in the unengaged position, but small enough such that the device cannot back out through the aperture in the engaged position. For example, the diameter of a circular aperture may be 1-2 mm larger than the profile of the soft tissue fixation device from the perspective of an insertion.
Once inserted, the soft tissue fixation device may be entered into the engaged position, for example, by advancing a screw into the proximal end of the first arm as discussed above in reference to
In the engaged position, the outer surface of the first arm is at an angle to the outer surface of the second arm, as shown in
As discussed above in reference to
The applicator shown in
The cannulated shaft further encloses a driver (not shown) passing within the shaft and connected to the knob 420 for applying a torque to the screw inserted into the threaded socket of the first arm (as described in reference to
The cannulated shaft may further serve as an extension with a small cross-sectional size to facilitate procedures that require maneuvering into small spaces and to reach target areas, such as during arthroscopic surgery. By having a low profile, the cannulated shaft provides for minimally invasive procedures when inserting the soft tissue fixation device.
In
In some embodiments, the soft tissue fixation device comprises a lip 510 on the proximal end of the first arm adjacent to the proximal end of the second arm. This lip 510 can provide a mechanical stopper to prevent the soft tissue fixation device from being inserted into the aperture beyond a certain depth. For example, if the lip of the soft tissue fixation device comprises a profile such that it extends beyond the superficial surface rim of the aperture (not depicted) while the device is in an engaged position, then the soft tissue fixation device may only be inserted to the point where the lip prevents further insertion. Notably, a notch cutout on the outer surface of the proximal aspect of the second arm could also create a relative lip of device material that overhangs the edge of cortical bone on the surface of an aperture when the device is in an engaged position. Also, a protrusion of device material creating a relative ridge on the outer surface of the proximal aspect of the second arm could create the same effect as a relative lip of device material created from a notch cutout.
Once the soft tissue fixation device captures soft tissue and if it then is placed below cortical bone in a fully engaged position, a larger profile created by the proximal ends of the device will prevent the device from backing out through the aperture in the cortical bone, as shown in
The foregoing description is provided to enable a person skilled in the art to practice the various configurations described herein. While the subject technology has been particularly described with reference to the various figures and configurations, it should be understood that these are for illustration purposes only and should not be taken as limiting the scope of the subject technology.
There may be many other ways to implement the subject technology. Various functions and elements described herein may be achieved with devices of forms that deviate from those shown without departing from the scope of the subject technology. Various modifications to these configurations will be readily apparent to those skilled in the art, and generic principles defined herein may be applied to other configurations. Thus, many changes and modifications may be made to the subject technology, by one having ordinary skill in the art, without departing from the scope of the subject technology.
It is understood that the specific order or hierarchy of steps in the processes disclosed is an illustration of exemplary approaches. Based upon design preferences, it is understood that the specific order or hierarchy of steps in the processes may be rearranged. Some of the steps may be performed simultaneously. For example, the insertion of the soft tissue fixation device may be done concurrently with the advancement of the screw into the first arm such that a gripping force is exerted on the soft tissue as the device is being inserted. The accompanying method claims present elements of the various steps in a sample order, and are not meant to be limited to the specific order or hierarchy presented.
Terms such as “top,” “upper,” “bottom,” “lower,” “right,” “left,” “up,” “down,” “forward,” “backward,” and the like as used in this disclosure should be understood as referring to an arbitrary frame of reference, rather than to the ordinary gravitational frame of reference. Thus, a top surface, a bottom surface, a front surface, and a rear surface may extend upwardly, downwardly, diagonally, or horizontally in a gravitational frame of reference.
A phrase such as “an aspect” does not imply that such aspect is essential to the subject technology or that such aspect applies to all configurations of the subject technology. A disclosure relating to an aspect may apply to all configurations, or one or more configurations. An aspect may provide one or more examples of the disclosure. A phrase such as an “aspect” may refer to one or more aspects and vice versa. A phrase such as an “embodiment” does not imply that such embodiment is essential to the subject technology or that such embodiment applies to all configurations of the subject technology. A disclosure relating to an embodiment may apply to all embodiments, or one or more embodiments. An embodiment may provide one or more examples of the disclosure. A phrase such as an “embodiment” may refer to one or more embodiments and vice versa. A phrase such as a “configuration” does not imply that such configuration is essential to the subject technology or that such configuration applies to all configurations of the subject technology. A disclosure relating to a configuration may apply to all configurations, or one or more configurations. A configuration may provide one or more examples of the disclosure. A phrase such as a “configuration” may refer to one or more configurations and vice versa.
Furthermore, to the extent that the term “include,” “have,” or the like is used in the description or the claims, such term is intended to be inclusive in a manner similar to the term “comprise” as “comprise” is interpreted when employed as a transitional word in a claim.
The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.
A reference to an element in the singular is not intended to mean “one and only one” unless specifically stated, but rather “one or more.” The term “some” refers to one or more. All structural and functional equivalents to the elements of the various configurations described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and intended to be encompassed by the subject technology.
