Patent Description:
In the operation of filling or inserting the medical filler into the bone, the current surgical methods commonly include the following:.

When using a mechanical expanding device (such as patents <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>) for bone expanding to generate a space in the bone, the expanding device is taken out after expanding, then a covering device is inserted, and then the operation for filling or stuffing of the medical filler is performed. This type of operation has the following disadvantages: Mechanical expanding devices crush the cancellous bone when expanding and the crushed fragments often fall into the mechanical expanding device, which causes the mechanical expanding device to get stuck, and makes the expanded element unable to be retracted (recovered to a contracted state), this results in that the entire mechanical expanding device is stuck. Thereby, it cannot be retracted from the expanded position.

When a filling expanding device (such as patents <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>) for bone expanding to generate a space in the bone are used, the expanding device is taken out after expanding, then a covering device is inserted, and then the operation for filling or stuffing of the medical filler is performed. Because the filling expanding device mostly puts a balloon into the bone, and uses high pressure to inject liquid (such as water) into the balloon (a variety of balloons are used for different needs), the balloon is inflated to push the cancellous bone into the bone to achieve the purpose of expanding. However, the device or method has many disadvantages, for example, the balloon must be connected to a nozzle, so when the filling of the liquid is under high pressure, it may cause the balloon to fall off from the nozzle, and the balloon may even burst.

Without expanding in advance, the covering device is directly placed into the bone and the medical filler is injected, and the pressure under which the medical filler is injected into the covering device is used to achieve the effect of spreading the bone. Under such a situation, the covering device is both an expanding device and a vertebrae fixation device when infusing the medical filler (such as patents <CIT>, <CIT>, <CIT>). Alternatively, the covering device is even abandoned, and an infusion device is directly used to inject the medical filler into the surgical position to enhance the fixation of the surgical position (such as patent <CIT>). This kind of surgery has the following disadvantages: Because no expanding is performed first, the range of infusion cannot be accurately controlled, so that the direction after finishing infusion may be different from that originally expected by the doctor, and it is even found that the covering device does not completely support the bone or the medical filler flows around in the bone after the medical filler is injected, and the medical filler may even flow out of the bone, or the concentration of the slurry medical filler may be too thin or the particle is too small, which makes it difficult to support the bone when infusing the medical filler, and greatly reduces the original effect.

The mechanical expanding device can be used as a vertebrae fixation device (such as patents <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>). After the mechanical expanding device is implanted into the bone and the bone is opened, the medical filler is injected, the medical filler is allowed to cover the mechanical expanding device, and the mechanical expanding device and the medical filler are left in the human body together after the filling is finished. This kind of surgical method uses no covering device, the flow direction of the medical filler cannot be effectively controlled, and thus it is possible for the medical filler to flow around the bone, and even to flow out of the bone. In addition, the medical filler cannot effectively and completely cover the mechanical expanding device, and the mechanical expanding device may thus slowly contract from a fully expanded state to an incompletely expanded state. As a result, the bones are not completely expanded, which means that the original purpose of the vertebrae fixation device is lost.

<CIT> discloses a device for bone fixation that includes: an expanding unit and an enclosing unit. The expanding unit includes two or more expanding structures capable of switching between an expanded state and a contracted state. The expanding unit includes a first expanding structure located near a first end thereof and a second expanding structure located near a second end thereof. The enclosing unit encloses the expanding unit and has a first end and a second end. The first end of the enclosing unit is secured at the first end of the expanding unit, and the second end of the enclosing unit is secured at the second end of the expanding unit. When the device for bone fixation is placed inside a bone, the expanding structures of the expanding unit are switched to the expanding state and thereby propping up the enclosing unit.

<CIT> discloses an apparatus and methods for bone fracture repair. The apparatus may include a structural support for positioning a first bone segment relative to a second bone segment. The apparatus may include an anchoring substrate. The anchoring substrate may be configured to compress the first bone segment to the second bone segment. The anchoring substrate may transmit tension from a distal bone segment anchor in the first bone segment to a proximal bone segment anchor in the second bone segment. The apparatus may be configured to be deployed percutaneously in an inner cavity of a bone. The apparatus may be installed in an open fracture. The apparatus may be expanded, self-expanding or configured for mechanical actuation. Some embodiments of the apparatus may include a central axis member that may be used in conjunction with expansion of one or both of the structural support and the anchoring substrate to configure the apparatus.

A covering device can be used to cover the expansion device as a vertebral fixation device (such as patent <CIT>). The covering device can effectively prevent fragments of the crushed cancellous bone from falling into the expansion device during expanding, so that the expansion device can be repeatedly expanded and contracted in the bone for expanding to adjust the direction of expanding or the size of the expanding range, and to control the range of infusion of the medical filler by the covering device when infusing the medical filler. After the infusion is finished, the medical filler can completely cover the expansion device. However, the pores of the covering device of this invention are not three-dimensional connecting pores, so the effect of the perfused medical filler and bones to achieve interdigitate is poor. Secondly, the medical filler in the covering device is solid, and its strength is far higher than that of cancellous bone in the bone, which is likely to cause stress concentration, which makes it difficult for bone cells near the implant to grow after surgery.

The present invention uses a three-dimensional porous device to control the infusion range of the medical filler, and since the three-dimensional porous device has a three-dimensional connecting pore structure, the medical filler subsequently injected is closer to the structure of the cancellous bone and less likely to have stress concentration. In addition, the medical filler flows through the three-dimensional connecting pore structure and contacts the vertebrae, which is more likely to achieve an interdigitate effect. Furthermore, the three-dimensional porous device can apply biodegradable materials, and the medical filler will form countless three-dimensional connecting channels therein with the three-dimensional porous device degraded later in the body, and the bone cells can grow into the medical filler through these connecting channels and form a denser connection with the medical filler.

These methods do not form part of the invention.

The present invention uses an adjustable expanding device to repeatedly expand and contract in the vertebrae to expand a space, and thereby adjust the scope and size of the space. After the expanding device expands a space, the pre-compressed porous device in the expanding device will expand and fill this space, and then a medical filler is injected into the porous device, so that the medical filler is interdigitated into the vertebrae and connected to the vertebrae by the porous device. The porous device can effectively control flow direction and a infusion range of the medical filler, and prevent the medical filler from scrambling in the vertebrae. On the other hand, because the porous device is a slurry structure with three-dimensional connecting pores, the injected medical filler will be closer to the structure of cancellous bone in the vertebrae, and mechanical performance thereof is also closer to cancellous bone, so the stress concentration problem is decreased, and postoperative bone cell growth is facilitated. Furthermore, the structure that forms the porous device will slowly degrade in the body and will form multiple connecting channels in the medical filler for the growing of bone cells, and more close combination to the medical filler.

An object of the present invention is to provide a vertebral fixation device.

The other object of the present invention is to provide a vertebral fixation device having an expanding device.

Another object of the present invention is to provide a vertebral fixation device having a porous device.

Yet another object of the present invention is to provide a vertebral fixation device having an expanding device and a porous device, the porous device being disposed inside the expanding device.

Still another object of the present invention is to provide a vertebral fixation device with a function of expanding vertebrae.

Another object of the present invention is to provide an expanding device which can repeatedly expand and contract a vertebral fixation device.

Still another object of the present invention is to provide a porous device that can control the flow direction and an infusion range of a medical filler.

Another object of the present invention is to provide a vertebral fixation device having a compressible and expandable porous device.

The other object of the present invention is to provide a vertebral fixation device that can be filled with a medical filler through a hollow operating lever.

Another object of the present invention is to provide a vertebral fixation device that can detach the expanding device from the operating lever and leave the expanding device in the vertebrae.

Still another object of the present invention is to provide a vertebral fixation device that can maintain an expanding device in an expanded state by a fixing mechanism.

A vertebral fixation device of the present invention comprises: an expanding device having a fixing end and a top end, wherein the expanding device is configured to be adjusted between an expanded state and a contracted state; and a three-dimensional porous device having a front end and a connecting end, wherein the front end of the three-dimensional porous device is connected with the top end of the expanding device, and the connecting end of the three-dimensional porous device is adapted for fixing to the fixing end of the expanding device; characterized in that the three-dimensional porous device is disposed inside the expanding device, and in that the expanding device and the three-dimensional porous device are configured to be placed into the vertebrae, the expanding device is configured to be adjusted to an expanded state to expand a space, and the three-dimensional porous device inside the expanding device is configured to expand and fill into the space, a medical filler is fillable into the three-dimensional porous device from the fixing end of the expanding device, and in that the three-dimensional porous device is configured effectively to control a flow direction and infusion range of the medical filler.

The above expanding device may be any conventional expanding device, such as patents <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, etc., or the expanding devices described in patents such as <CIT> and <CIT>, the expanding device uses mechanical force to open a space, rather than using the pressure of a medical filler to open the space, so that the concentration of the medical filler can be avoided from being too dilute to expand the space, or from being too thick resulting in poor infusion or even excessive infusion pressure that causes the injection tool to burst. The expanding device which is lantern-shaped (as shown in <FIG>, <FIG>, <FIG>, <FIG>) is preferred.

The structure of the three-dimensional porous device may be a three-dimensional connecting pore structure (as shown in <FIG>), or may at least partly be a three-dimensional connecting pore structure (as shown in <FIG>). The three-dimensional porous device can even prevent the medical filler flowing out of the vertebrae, causing a risk to the patient, and effectively achieve the interdigitate effect, so that the medical filler and the vertebrae are connected more closely. In addition, the size, porosity, etc. of the three-dimensional connecting pore structure can be adjusted to not only control the overall mechanical strength of the medical filler and the three-dimensional porous device to make its mechanical performance closer to the strength of cancellous bone in the vertebrae for preventing stress concentration and being beneficial to the growth of bone cells after surgery, but also be used to adjust the smoothness of the infusion of the medical filler into the three-dimensional porous device.

The aforementioned three-dimensional connecting pore structure may further be a three-dimensional connecting pore structure with a fixed pore size (see <FIG>), a three-dimensional connecting pore structure with different pore sizes (see <FIG>), or a three-dimensional connecting pore structure being hollow inside (see <FIG>) can be selected with three-dimensional porous devices with appropriate pore sizes according to the different thicknesses of the medical filler or bone looseness. On the one hand, the smoothness of the infusion of the medical filler can be increased. On the other hand, the mechanical performance of the completely formed medical filler and the three-dimensional porous device can be adjusted through the selection of the pore size.

The porous device is an expandable porous device, and the expandable porous device is pre-compressed and placed in the expanding device, and after the expanding device is expanded to create a space, the space may be automatically filled to facilitate subsequent infusion of the medical filler. The expandable porous device can be foam, sponge, or any compressible/expandible porous elastomer.

In the above three-dimensional porous device, the material forming the structure of the porous device may be any conventional biocompatible material, such as polyethylene, polyurethane, polyvinyl alcohol, nylon, silicone, etc., or further be a biodegradable material such as polylactic acid, gelatin, alginate, polyglycolic acid, polyhydroxy fatty acid ester, polychinolactone, etc. In this way, after the porous device and the medical filler are implanted in the human body, the porous device can slowly degrade in the human body, the structure of the porous device will form multiple connecting channels in the medical filler, and the bone cells can grow into the medical filler through these connecting channels, forming a closer intertwined connection with the medical filler. The material of the porous device is preferred to be a biodegradable material.

In the structure mentioned above forming a three-dimensional porous device, the curved plane boundary of any pore is composed of the above-mentioned material in shape of filament/thin line, and the diameter of the filament/thin line (hereinafter refer to as the structure diameter) may be smaller than <NUM>, the diameter of the connecting channel left from the porous device after degradation in the body can be controlled through the selection of the structure diameter. The structure diameter of the porous device is preferred to be <NUM> to <NUM>. It is also easier for bone cells to grow in a range of <NUM>-<NUM>.

In the above three-dimensional porous device, the front end, the connecting end of the porous device can be respectively fixed to the top end/the fixing end of the expanding device by ring-shaped fixing members (as shown in <FIG>, <FIG>, <FIG>, with numeral <NUM>) or any conventional fixing manner. In this way, the porous device can be prevented from being displaced due to the excessive infusion pressure of the medical filler, which would cause the medical filler to overflow in an unexpected filling direction, and cause the patient possible paralysis or death.

The vertebral fixation device may further include an operating lever with a connecting end and a manipulating end, wherein the connecting end is connected to the top end or the fixing end of the expanding device. The expanding device is adjusted to be in an expanded state or contracted state by relative movement of stretching or rotating (as shown in <FIG>) with the operating lever (as shown in <FIG>, with numeral <NUM>).

The operating lever mentioned above may further be a hollow operating lever, and the hollow operating lever inside the expanding device has one or more perforations (for example, as shown in <FIG>, with numeral <NUM>) allowing the medical filler to flow to the porous device through the perforations. The perforation can be any known form of perforation, such as grooves, pores, etc..

The operating lever may further include a second detachable mechanism (for example, as shown in <FIG>, <FIG>, <FIG>, with numeral <NUM>). After the medical filler is filled in the expanding device and the porous device, the second detachable mechanism detaches the expanding device from at least part of the operating lever, and leaves the expanding device and the porous device in the vertebrae. The second detachable mechanism may be any conventional detachable mechanism, such as screwing, engaging, locking or buckling, while screwing is preferred.

The above operating lever may further include a fixing mechanism (for example, <FIG>, <FIG>, <FIG>, with numeral <NUM>). After the expanding device is expanded to be in the expanded state, the expanding device may be maintained in the expanded state by the fixing mechanism to facilitate the subsequent expansion of the porous device and fill the expanding device, and the medical filler is filled into the expanding device. The fixing mechanism may be any conventional fixing mechanism, such as an expanding and fixing mechanism, a buckling fixing mechanism, a locking fixing mechanism, or a screwing fixing mechanism, etc., while the engaging and fixing mechanisms are preferred.

The above-mentioned medical filler may be any conventional consolidable and slurry medical filler, such as bone cement. The above-mentioned consolidable and slurry medical filler preferably is a medical filler with osteo-conductive and/or osteo-inductive materials added thereto, such as the conventional hydroxyapatite, calcium phosphate-based bone fillers, while it is preferred to add bone-leading medical fillers, such as the conventional SrHA-based medical filler.

A vertebral fixation device of the present invention can include an operating lever having a connecting end and a manipulating end, wherein the connecting end is configured for connection to the top end of the expanding device, and wherein the expanding device is configured to be adjusted between an expanded state and a contracted state by relative movement of the operating lever; a hollow jointing tube having a front end and a rear end, wherein the front end of the hollow jointing tube and the fixing end of the expanding device form a detachable connection; an auxiliary expanding device having a jointing end and a manipulating end, wherein the jointing end of the auxiliary expanding device and the rear end of the hollow jointing tube form a detachable connection; and
an injection tool adapted for connection to the rear end of the hollow jointing tube or to the manipulating end of the operating lever, and the injection tool is adapted to inject the medical filler into the three-dimensional porous device via the hollow jointing tube or via the operating lever; wherein the auxiliary expanding device is configured to expand the expanding device by way of the operating lever, the auxiliary expanding device is configured to be detachable from the expanded expanding device, and the injection tool is configured to be installable with the expanded expanding device in order to fill the medical filler.

The above hollow jointing tube (for example, as shown in <FIG>, with numeral <NUM>) may be any conventional hollow jointing tube.

The above-mentioned auxiliary expanding device (see, for example, reference numeral <NUM> in <FIG>) is used to adjust the expanding device to an expanded state or a contracted state by using its connection with the operating lever and the connection between the operating lever and the expanding device. After expanding the expanding device, the detachable connection between the auxiliary expanding device and the hollow jointing tube is used to disassemble the auxiliary expanding device, and then the injection tool is installed to inject the medical filler.

The above-mentioned detachable connection method can be any conventional detachable connection method (similar to those shown in <FIG> and <FIG>), such as snapping, locking, buckling, screwing, etc..

The operating lever mentioned above may be used to adjust the expanding device to be in the expanded state or the contracted state by the relative movement of stretching or rotating with the expanding device (as shown in <FIG>, <FIG>, <FIG>).

The operating lever mentioned above may further be a hollow operating lever, and the hollow operating lever inside the expanding device has one or more perforations allowing the medical filler to flow to the porous device through the perforations. The perforation can be any form of perforation, such as grooves, pores, etc..

For the above injection tool (as shown in <FIG>, numeral <NUM>), the injection method may include: detaching the auxiliary expanding device and the operating lever before infusion, and then connecting the injection tool with the hollow jointing tube for infusion. The injection method also may include: detaching the auxiliary expanding device before the infusion, and then connecting the injection tool with the hollow operating lever for infusion.

The above vertebral fixation device may further include an extension tube (see <FIG>, reference numeral <NUM>). The extension tube is used together with the injection tool, which is respectively connected with the rear end of the hollow jointing tube or the manipulating end of the operating lever, and connected with the injection tool; the connection can be any conventional connection method, such as snapping, locking, screwing, etc..

The extension tube may be any conventional extension tube.

The injection tool can be any conventional injection tool.

The vertebral fixation device above may further include a blocking device used to connect the fixing end of the expanding device after perfusing or inserting the medical filler completely, and the medical filler is blocked by the blocking device from flowing out or dropping out. The connection between the blocking device and the fixing end of the expanding device can be any conventional connection, such as screwing, snapping, locking, buckling, etc., the connection method therein is preferred to be screwing or engaging.

The present invention will be apparent to those skilled in the art by reading the following detailed description of a preferred embodiment thereof, with reference to the attached drawings, in which:.

The following description with drawings and element symbols provides more detail of the embodiment of the present invention, so that those skilled in the art can implement the present invention after studying this specification.

<FIG> is a schematic diagram of a vertebral fixation device according to a preferred specific embodiment of the present invention. A porous device <NUM> is arranged inside an expanding device <NUM>, in which a front end <NUM> of the porous device and a connecting end <NUM> of the porous device respectively use a ring-shaped fixing member <NUM> (not shown in <FIG>, refer to <FIG> and <FIG>) to connect with a top end <NUM> of the expanding device and a fixing end <NUM> of the expanding device, so as to prevent deviation of the porous device <NUM> due to the excessive infusion pressure of the medical filler during infusion. When the expanding device <NUM> is in a contracted state, the porous device <NUM> is also in a compressed state. The operating lever <NUM> has a second detachable mechanism <NUM>. After the medical filler is filled into the expanding device <NUM> and the porous device <NUM> via the operating lever <NUM>, the expanding device <NUM> and at least part of the operating lever <NUM> is detached by way of the second detachable mechanism <NUM>, and the expanding device <NUM>, the porous device <NUM>, and the medical filler are left in the vertebrae. An operating end <NUM> of the operating lever is connected to a jointing end <NUM> of the auxiliary expanding device <NUM>, and a manipulating end <NUM> of the auxiliary expanding device carries the operating lever <NUM> to control the expanding device <NUM> to expand and contract.

<FIG> is a schematic diagram of the expanding device <NUM> and the porous device <NUM> of <FIG> in an expanded state. After the expanding device <NUM> is expanded, the internal porous device <NUM> automatically expands and fills the space inside the expanding device <NUM>.

<FIG> is an enlarged cross-sectional view of the expanding device <NUM> and the porous device <NUM> of <FIG>. After the expanding device <NUM> is expanded to be in the expanded state, the expanding device <NUM> is maintained in the expanded state by the engaging and fixing mechanism <NUM> of the operating lever <NUM>, so as to facilitate the subsequent expansion of the porous device <NUM> which is to be filled to the expanding device <NUM>. After the medical filler is injected into the porous device <NUM> and the expanding device <NUM>, the second detachable mechanism <NUM> can be used to detach the expanding device <NUM> and at least part of the operating lever <NUM>, and leave the expanding device <NUM> and the porous device <NUM> in the vertebrae.

<FIG> is an enlarged cross-sectional view of the expanding device <NUM>, the porous device <NUM>, and the operating lever <NUM> of <FIG>. The porous device <NUM> is used to fix the front end <NUM> and the connecting end <NUM> respectively to the top end <NUM> and the fixing end <NUM> of the expanding device through the ring-shaped fixing member <NUM>.

<FIG> is another schematic diagram of the porous device <NUM> and the operating lever <NUM> of <FIG>.

<FIG> is a schematic diagram of a vertebral fixation device according to a preferred embodiment of the present invention. After expanding and detaching the hollow jointing tube <NUM> and the auxiliary expanding device <NUM> (as shown in <FIG> and <FIG>) by the expanding device <NUM>, the manipulating end <NUM> of the operating lever is connected to an extension tube <NUM>, and the connection between the manipulating end <NUM> of the operating lever and the extension tube <NUM> is a detachable connection. The medical filler (not shown in the FIG. ) is injected into the porous device through the injection tool <NUM>, the extension tube <NUM>, and the operating lever <NUM>. After the medical filler (not shown) is injected to the porous device <NUM> by the injection tool <NUM>, the extension tube <NUM> can be detached through a detachable connection, and the second detachable mechanism <NUM> (refer to <FIG> and <FIG>) can be used to detach the expanding device <NUM> and at least part of the operating lever <NUM>, and leave the expanding device <NUM> and the porous device <NUM> in vertebrae.

<FIG> is a schematic diagram of a vertebral fixation device according to another preferred embodiment of the present invention. A front end <NUM> of the hollow jointing tube is connected to the expanding device <NUM> by a detachable connection, and after the expanding device <NUM> is expanded and the operating lever <NUM> and the auxiliary expanding device <NUM> are detached (refer to <FIG> and <FIG>), connection between a rear end <NUM> of the hollow jointing tube and the extension tube <NUM> is also a detachable connection. After the medical filler is injected into the porous device <NUM> by the injection tool <NUM>, the extension tube <NUM> and the hollow jointing tube <NUM> can be detached through the detachable connection of the rear end <NUM> of the hollow jointing tube. Also, the detachable connection (refer to <FIG> and <FIG>) of the front end <NUM> of the hollow jointing tube can be used to detach the expanding device <NUM> and the hollow jointing tube <NUM>, and leave the expanding device <NUM> and the porous device <NUM> in vertebrae.

<FIG> is a schematic diagram of a vertebral fixation device according to another preferred embodiment of the present invention. The porous device <NUM> is arranged inside the expanding device <NUM>, in which the front end <NUM> of the porous device and the connecting end <NUM> of the porous device respectively use the ring-shaped fixing member <NUM> (not shown in <FIG>, refer to <FIG> and <FIG>) to connect with the top end <NUM> of the expanding device and the fixing end <NUM> of the expanding device, so as to prevent deviation of the porous device <NUM> due to the excessive infusion pressure of the medical filler during infusion. When the expanding device <NUM> is in the contracted state, the porous device <NUM> is also in a compressed state. The fixing end <NUM> of the expanding device and the jointing end <NUM> of the operating lever are connected by a screwed first detachable mechanism <NUM> (as shown in <FIG>). After the medical filler is injected into the porous device <NUM>, the expanding device <NUM> is detached from the operating lever <NUM> by way of the first detachable mechanism <NUM>, and the expanding device <NUM> is left in the vertebrae with the porous device <NUM> and the medical filler therein. The operating end <NUM> of the operating lever and a jointing end <NUM> of an auxiliary expanding device <NUM> are connected. A manipulating end <NUM> of the auxiliary expanding device is used to drive the operating lever <NUM> to control the expansion and contraction of the expanding device <NUM>.

<FIG> is a schematic diagram of the expanding device <NUM> and the porous device <NUM> of <FIG> in the expanded state. After the expanding device <NUM> is expanded, the internal porous device <NUM> automatically expands and fills the space inside the expanding device <NUM>.

<FIG> are schematic diagrams of expanding devices of a vertebral fixation device according to preferred specific embodiments of the present invention. <FIG>, <FIG>, <FIG>, and <FIG> illustrate the expanding device <NUM> in the contracted state. <FIG>, <FIG>, <FIG>, <FIG> illustrate a lantern-shaped expanding device <NUM> in the expanded state. The hollow operating lever <NUM> inside the expanding device <NUM> in <FIG>, <FIG> has a perforation <NUM>, and the medical filler may flow from the opening of the fixing end <NUM> of the expanding device through the perforation <NUM> of the hollow operating lever <NUM> into the porous device <NUM>.

<FIG> illustrates a plane-shaped expanding device <NUM> in the contracted state. <FIG> illustrates a plane-shaped expanding device <NUM> adjusted to be in the expanded state by the operating lever <NUM>. <FIG> illustrates a blade-shaped expanding device <NUM> in the contracted state. <FIG> illustrates the blade-shaped expanding device <NUM> in the expanding state. <FIG> illustrates the expanding device <NUM> in the contracted state. <FIG> illustrates the expanding device <NUM> in the expanded state.

<FIG> are schematic diagrams of three porous devices <NUM> of the vertebral fixation device according to preferred specific embodiments of the present invention. <FIG> is the porous device <NUM> having a three-dimensional connecting pore structure with pores <NUM> of uniform size. The size of the pores <NUM> of the porous device may be controlled to adjust the infusion pressure and the flow smoothness of the medical filler. The material of the structure <NUM> of the porous device is biodegradable. After the porous device <NUM> and the medical filler (not shown) are implanted in the human body, the structure <NUM> of the porous device will slowly degrade in the human body, and multiple connecting channels will be formed in the medical filler. Bone cells can grow into the medical filler through these connecting channels, forming a more intertwined connection with the medical filler.

<FIG> illustrates the porous device <NUM> having a hollow interior and a three-dimensional connecting pore structure with uniformly-sized pores <NUM> on the periphery. In this way, the medical filler can be injected into the porous device <NUM> with better fluidity and smoothness, and the flow direction of the medical filler may be controlled through the three-dimensional connecting pore structure on the periphery, and the interdigitate effect of the medical filler may be increased to make closer connection with the vertebrae.

<FIG> illustrates the porous device <NUM> having three-dimensional connecting pore structures with different porosities. The porous device <NUM> has an the inner layer <NUM> having a larger porosity and an outer layer <NUM> having a smaller porosity may be used to increase the smoothness of the medical filler injected to the porous device <NUM>, and reduce the infusion pressure, and the porous device <NUM> with a smaller porosity in the outer layer <NUM> is used to effectively achieve interdigitate effect of bone, and to control/limit the flow direction of the medical filler, so as not to cause excessive overflow of the medical filler, which causes danger to the patient.

<FIG> are schematic diagrams of two expanding methods of a vertebral fixation (methods are not claimed). <FIG> illustrate the expanding device <NUM> extended by the relative stretching motion of the operating lever <NUM> and the expanding device <NUM> from the contracted state to the expanded state.

<FIG> are respectively schematic diagrams of the connection relationship between two expanding devices <NUM> and operating lever <NUM> according to preferred specific embodiments of the present invention. <FIG> illustrates that the operating lever <NUM> is connected to the expanding device <NUM> by the screwed second detachable mechanism <NUM>, so as to inject the medical filler, and then the expanding device <NUM> is detached from the operating lever <NUM> or part of the operating lever <NUM>, and the expanding device <NUM> is left in the vertebrae. <FIG> illustrates that the operating lever <NUM> can be connected to the expanding device <NUM> by the engaged second detachable mechanism <NUM>.

<FIG>, <FIG> are schematic diagrams of preferred specific examples of the connection relationship between the tip <NUM> and the operating lever <NUM> of the two kinds of expanding devices of the vertebral fixation device of the present invention. <FIG> illustrates the top end <NUM> of the expanding device and the operating lever <NUM> forming a detachable connection by engaging. <FIG> illustrates the top end <NUM> of the expanding device and the operating lever <NUM> forming a detachable connection by screwing.

<FIG> are schematic diagrams of surgical steps of a vertebral fixation device according to the present invention. <FIG> illustrates the expanding device <NUM> and the porous device <NUM>, in the contracted state, are placed in the vertebrae. <FIG> illustrates that the operating lever <NUM> and the auxiliary expanding device <NUM> are used to expand the expanding device <NUM> from the contracted state to the expanded state and expand a space in the vertebrae, the porous device <NUM> inside the expanding device <NUM> will expand and fill the space inside the expanding device <NUM>. <FIG> illustrates that the auxiliary expanding device <NUM> is detached, and the injection tool <NUM> and the extension tube <NUM> are connected, and the medical filler (not shown, refer to <FIG>) is injected into the porous device <NUM> and the expanding device <NUM> through the extension tube <NUM> and the operating lever <NUM> through the injection tool <NUM>. <FIG> illustrates that the injection tool <NUM> and the extension tube <NUM> are detached, and the expanding device <NUM> is detached from part of the operating lever <NUM> by the second detachable mechanism <NUM> of the operating lever <NUM>, and the expanding device <NUM> and the porous device <NUM> are left in the vertebrae.

Claim 1:
A vertebral fixation device comprising:
an expanding device (<NUM>) having a fixing end (<NUM>) and a top end (<NUM>), wherein the expanding device (<NUM>) is configured to be adjusted between an expanded state and a contracted state; and
a three-dimensional porous device (<NUM>) having a front end (<NUM>) and a connecting end (<NUM>), wherein the front end (<NUM>) of the three-dimensional porous device (<NUM>) is connected with the top end (<NUM>) of the expanding device (<NUM>), and the connecting end (<NUM>) of the three-dimensional porous device (<NUM>) is adapted for fixing to the fixing end (<NUM>) of the expanding device (<NUM>);
characterized in that the three-dimensional porous device (<NUM>) is disposed inside the expanding device (<NUM>),
and in that the expanding device (<NUM>) and the three-dimensional porous device (<NUM>) are configured to be placed into the vertebrae, the expanding device (<NUM>) is configured to be adjusted to an expanded state to expand a space, and the three-dimensional porous device (<NUM>) inside the expanding device (<NUM>) is configured to expand and fill into the space, a medical filler (<NUM>) is fillable into the three-dimensional porous device (<NUM>) from the fixing end (<NUM>) of the expanding device (<NUM>),
and in that the three-dimensional porous device (<NUM>) is configured effectively to control a flow direction and infusion range of the medical filler.