Patent Application
20090222097
The present disclosure relates generally to orthopedics and spinal surgery. More specifically, the present disclosure relates to nucleus implants.
In human anatomy, the spine is a generally flexible column that can take tensile and compressive loads. The spine also allows bending motion and provides a place of attachment for ribs, muscles and ligaments. Generally, the spine is divided into three sections: the cervical spine, the thoracic spine and the lumbar spine. The sections of the spine are made up of individual bones called vertebrae. Also, the vertebrae are separated by intervertebral discs, which are situated between adjacent vertebrae.
The intervertebral discs function as shock absorbers and as joints. Further, the intervertebral discs can absorb the compressive and tensile loads to which the spinal column may be subjected. At the same time, the intervertebral discs can allow adjacent vertebral bodies to move relative to each other a limited amount, particularly during bending, or flexure, of the spine. Thus, the intervertebral discs are under constant muscular and/or gravitational pressure and generally, the intervertebral discs are the first parts of the lumbar spine to show signs of “wear and tear”.
Facet joint degeneration is also common because the facet joints are in almost constant motion with the spine. In fact, facet joint degeneration and disc degeneration frequently occur together. Generally, although one may be the primary problem while the other is a secondary problem resulting from the altered mechanics of the spine, by the time surgical options are considered, both facet joint degeneration and disc degeneration typically have occurred. For example, the altered mechanics of the facet joints and/or intervertebral disc may cause spinal stenosis, degenerative spondylolisthesis, and degenerative scoliosis.
One surgical procedure for treating these conditions is spinal arthrodesis, i.e., spine fusion, which can be performed anteriorally, posteriorally, and/or laterally. The posterior procedures include in-situ fusion, posterior lateral instrumented fusion, transforaminal lumbar interbody fusion (“TLIF”) and posterior lumbar interbody fusion (“PLIF”). Solidly fusing a spinal segment to eliminate any motion at that level may alleviate the immediate symptoms, but for some patients maintaining motion may be beneficial. It is also known to surgically replace a degenerative disc or facet joint with an artificial disc or an artificial facet joint, respectively. Additionally, it is known to surgically remove nucleus pulposus material from within an intervertebral disc and replace the nucleus pulposus material with an artificial nucleus.
A nucleus implant is disclosed. The nucleus implant can be configured to be installed within an intervertebral disc between an inferior vertebra and a superior vertebra. The nucleus implant can include an expandable core and an expandable chamber that can be disposed at least partially around the expandable core. The expandable chamber can be expanded from a deflated position to an inflated position. Further, a hardness of the expandable core, when inflated, can be greater than or equal to a hardness of the expandable chamber when inflated.
It will be noted that the chamber that is at least partially peripheral enables, when it is inflated, accurate positioning of the core. This implant provides a great mobility from one vertebra to another vertebra (rotation and/or flexion). Since the core is harder than the chamber it acts as a pivot, thereby making these movements easier.
In another embodiment, a nucleus implant is disclosed. The nucleus implant can be configured to be installed within an intervertebral disc between an inferior vertebra and a superior vertebra. The nucleus implant can include an expandable core and a toroid shaped expandable chamber that can be disposed at least partially around the expandable core. Moreover, a hardness of the expandable core, when inflated, can be greater or equal to than a hardness of the toroid shaped expandable chamber when inflated.
In yet another embodiment, a nucleus implant is disclosed. The nucleus implant can be configured to be installed within an intervertebral disc between an inferior vertebra and a superior vertebra. The nucleus implant can include an expandable core that can include an outer surface. Also, the nucleus implant can include a first toroid shaped expandable chamber that can be disposed at least partially around the expandable core and a second toroid shaped expandable chamber that can be disposed at least partially around the first toroid shaped expandable chamber. A hardness of the expandable core can be greater than or equal to a hardness of the first expandable chamber and the hardness of the first expandable chamber can be greater than or equal to a hardness of the second expandable chamber when the expandable core, the first expandable chamber, and the second expandable chamber are inflated.
In still another embodiment, a nucleus implant is disclosed. The nucleus implant can be configured to be installed within an intervertebral disc between an inferior vertebra and a superior vertebra. The nucleus implant can include an expandable core and a bowl shaped expandable chamber that can be disposed at least partially around the expandable core. A hardness of the expandable core when inflated can be greater than or equal to a hardness of the bowl shaped expandable chamber when inflated.
In yet still another embodiment, a nucleus implant is disclosed. The nucleus implant can be configured to be installed within an intervertebral disc between an inferior vertebra and a superior vertebra. The nucleus implant can include an expandable core that can include an outer surface and a U shaped expandable chamber that can be disposed at least partially around the expandable core. A hardness of the expandable core when inflated can be greater than or equal to a hardness of the U shaped expandable chamber when inflated.
In another embodiment, a method of installing a nucleus implant within an intervertebral disc between an inferior vertebra and a superior vertebra of a patient is disclosed. The method can include implanting the nucleus implant within the intervertebral disc. Further, the nucleus implant can include an expandable core and an expandable chamber at least partially around the expandable core. The method can also include inflating the expandable core and inflating the expandable chamber around the expandable core. A hardness of the expandable core when inflated can be greater than or equal to a hardness of the expandable chamber when inflated.
In yet another embodiment, a method of installing a nucleus implant within an intervertebral disc between an inferior vertebra and a superior vertebra of a patient is disclosed. The method can include implanting the nucleus implant within the intervertebral disc. The nucleus implant can include an expandable core, a first expandable chamber at least partially around the expandable core, and a second expandable chamber at least partially around the first expandable chamber. Moreover, the method can inflating the expandable core, inflating the first expandable chamber around the expandable core, inflating the second expandable chamber around the first expandable chamber. A hardness of the expandable core when inflated can be greater than or equal to a hardness of the first expandable chamber when inflated. Also, the hardness of the first expandable chamber when inflated can be greater than or equal to a hardness of the second expandable chamber when inflated.
In still yet another embodiment, a method of installing a nucleus implant within an intervertebral disc between an inferior vertebra and a superior vertebra of a patient is disclosed. The method can include implanting the nucleus implant within the intervertebral disc. The nucleus implant can include an expandable core and an expandable chamber at least partially around the expandable core. Additionally, the method can include inflating the expandable chamber and inflating the expandable core within the expandable chamber. A hardness of the expandable core when inflated can be greater than or equal to a hardness of the expandable chamber when inflated.
Referring initially to
As shown in
As depicted in
Referring to
As illustrated in
It is well known in the art that the vertebrae that make up the vertebral column have slightly different appearances as they range from the cervical region to the lumbar region of the vertebral column. However, all of the vertebrae, except the first and second cervical vertebrae, have the same basic structures, e.g., those structures described above in conjunction with
Referring now to
The nucleus pulposus 404 is the inner gel material that is surrounded by the annulus fibrosus 402. It makes up about forty percent (40%) of the intervertebral disc 400. Moreover, the nucleus pulposus 404 can be considered a ball-like gel that is contained within the lamellae 406. The nucleus pulposus 404 includes loose collagen fibers, water, and proteins. The water content of the nucleus pulposus 404 is about ninety percent (90%) at birth and decreases to about seventy percent (70%) by the fifth decade.
Injury or aging of the annulus fibrosus 402 may allow the nucleus pulposus 404 to be squeezed through the annulus fibers either partially, causing the disc to bulge, or completely, allowing the disc material to escape the intervertebral disc 400. The bulging disc or nucleus material may compress the nerves or spinal cord, causing pain. Accordingly, the nucleus pulposus 404 can be removed and replaced with an artificial nucleus.
Referring to
As illustrated in
The expandable chamber 506 can define an inner surface 508 and an outer surface 510. In a particular embodiment, the inner surface 508 of the expandable chamber 506 can be attached to the outer surface 504 of the expandable core 502, for example, by gluing. As such, proper placement of the expandable chamber 506 can be based on the placement of the expandable core 502. Alternatively, the expandable chamber 506 can be separate from the expandable core 502 and the expandable chamber 506 may engage the expandable core 502 after the expandable chamber 506 is properly inflated. Alternatively, the core and the chamber may be made of one and the same element, for example, for the sake of convenience.
As depicted in
In a particular embodiment, the nucleus implant 500 can include a first self-sealing valve (not shown) within the outer surface 504 of the expandable core 502, e.g., adjacent to the first injection tube 512. Moreover, the nucleus implant 500 can include a second self-sealing valve (not shown) within the outer surface 510 of the expandable chamber 506, e.g., adjacent to the second injection tube 514. The self-sealing valves can prevent the expandable core 502 and the expandable chamber 506 from leaking material after the expandable core 502 and the expandable chamber 506 are inflated and the injection tubes 512, 514 are removed.
In a particular embodiment, the expandable core 502 and the expandable chamber 506 can be inflated so the inner surface 508 of the expandable chamber 506 engages the outer surface of the expandable core 502 and the outer surface 510 of the expandable chamber 506 engages the annulus fibrosis 604. The nucleus implant 500 can provide shock-absorbing characteristics substantially similar to the shock absorbing characteristics provided by the nucleus pulposus. Further, in a particular embodiment, the hardness of the expandable core 502 of the nucleus implant 500 is greater than or equal to the hardness of the material used to inflate the expandable chamber 506, i.e., after the materials used to inflate the expandable core 502 and the expandable chamber 506 are cured. Alternatively, the viscosity of the material used to inflate the expandable core 502 is greater than or equal to the viscosity of the material used to inflate the expandable chamber 506. As one example, the core has a hardness of 55 Shore D and the expandable chamber has a hardness of 40 Shore D.
Additionally, in a particular embodiment, the height of the expandable core 502 is greater than or equal to the height of the expandable chamber 506 when each is properly expanded within the intervertebral disc 600. As shown in
In a particular embodiment, the expandable core 502, the expandable chamber 506, or both the expandable core 502 and the expandable chamber 506 of the nucleus implant 500 can be inflated with one or more injectable extended use approved medical materials that remain elastic after curing. Further, the injectable extended use approved medical materials can include polymer materials that remain elastic after curing.
For example, the polymer materials can include polyurethane materials, polyolefin materials, polyether materials, silicone materials, or a combination thereof. Further, the polyolefin materials can include polypropylene, polyethylene, halogenated polyolefin, flouropolyolefin, or a combination thereof. The polyether materials can include polyetherketone (PEK), polyetheretherketone (PEEK), polyetherketoneketone (PEKK), polyaryletherketone (PAEK), or a combination thereof. Also, the silicone materials can include a silicone hydrogel.
In an alternative embodiment, the injectable extended use approved medical materials can include one or more fluids such as sterile water, saline, or sterile air. In alternative embodiments, the expandable core 502, the expandable chamber 506, or both the expandable core 502 and the expandable chamber 506 of the nucleus implant 500 can be inflated with one or more of the following: fibroblasts, lipoblasts, chondroblasts, differentiated stem cells or other biologic factor which would create a motion limiting tissue when injected into a bioresorbable motion limiting scaffold.
In a particular embodiment, the nucleus implant 500 can be installed using a posterior surgical approach, as shown. Further, the nucleus implant 500 can be installed through a posterior incision 606 made within the annulus fibrosus 604 of the intervertebral disc 600. Alternatively, the nucleus implant 500 can be installed using an anterior surgical approach, a lateral surgical approach, or any other surgical approach well known in the art.
Referring to
As illustrated in
The thus shaped chamber that is arranged around the core may enable accurate positioning of the core. The accuracy of the core positioning may be increased by inflating the chamber with a uniform pressure.
The expandable chamber 806 can define an inner surface 808 and an outer surface 810. In a particular embodiment, the inner surface 808 of the expandable chamber 806 can be attached to the outer surface 804 of the expandable core 802. As such, proper placement of the expandable chamber 806 can be based on the placement of the expandable core 802. Alternatively, the expandable chamber 806 can be separate from the expandable core 802 and the expandable chamber 806 may engage the expandable core 802 after the expandable chamber 806 and the expandable core 802 are properly inflated.
As depicted in
In a particular embodiment, the nucleus implant 800 can include a first self-sealing valve (not shown) within the outer surface 804 of the expandable core 802, e.g., adjacent to the first injection tube 812. Moreover, the nucleus implant 800 can include a second self-sealing valve (not shown) within the outer surface 810 of the expandable chamber 806, e.g., adjacent to the second injection tube 814. The self-sealing valves can prevent the expandable core 802 and the expandable chamber 806 from leaking material after the expandable core 802 and the expandable chamber 806 are inflated and the injection tubes 812, 814 are removed.
In a particular embodiment, the expandable core 802 and the expandable chamber 806 can be inflated so the inner surface 808 of the expandable chamber 806 engages the outer surface of the expandable core 802 and the outer surface 810 of the expandable chamber 806 engages the annulus fibrosis 904. Further, portions of the outer surface 810 of the expandable chamber 806 can engage the superior vertebra 1000 and an inferior vertebra 1002. Moreover, when the expandable core 802 and the expandable chamber 806 are expanded, or otherwise inflated, a portion of the expandable chamber 806 is located between the expandable core 802 and the superior vertebra 1000.
The nucleus implant 800 can provide shock-absorbing characteristics substantially similar to the shock absorbing characteristics provided by the nucleus pulposus. Further, in a particular embodiment, the hardness of the expandable core 802 of the nucleus implant 800 is greater than or equal to the hardness of the material used to inflate the expandable chamber 806, i.e., after the materials used to inflate the expandable core 802 and the expandable chamber 806 are cured. Alternatively, the viscosity of the material used to inflate the expandable core 802 is greater than or equal to the material used to inflate the expandable chamber 806. As shown in
In a particular embodiment, the expandable core 802, the expandable chamber 806, or both the expandable core 802 and the expandable chamber 806 of the nucleus implant 800 can be inflated with one or more injectable extended use approved medical materials that remain elastic after curing. Further, the injectable extended use approved medical materials can include polymer materials that remain elastic after curing.
For example, the polymer materials can include polyurethane materials, polyolefin materials, polyether materials, silicone materials, or a combination thereof. Further, the polyolefin materials can include polypropylene, polyethylene, halogenated polyolefin, flouropolyolefin, or a combination thereof. The polyether materials can include polyetherketone (PEK), polyetheretherketone (PEEK), polyetherketoneketone (PEKK), polyaryletherketone (PAEK), or a combination thereof. Also, the silicone materials can include a silicone hydrogel.
In an alternative embodiment, the injectable extended use approved medical materials can include one or more fluids such as sterile water, saline, or sterile air. In alternative embodiments, the expandable core 802, the expandable chamber 806, or both the expandable core 802 and the expandable chamber 806 of the nucleus implant 800 can be inflated with one or more of the following: fibroblasts, lipoblasts, chondroblasts, differentiated stem cells or other biologic factor which would create a motion limiting tissue when injected into a bioresorbable motion limiting scaffold.
In a particular embodiment, the nucleus implant 800 can be installed using a posterior surgical approach, as shown. Further, the nucleus implant 800 can be installed through a posterior incision 906 made within the annulus fibrosus 904 of the intervertebral disc 900. When the chamber has been inflated, the core is not able to get out through the incision 906 after its installation. This is because the bottom of the chamber having a generally inverted-bowl shape is placed between the incision and the core. Alternatively, the nucleus implant 800 can be installed using an anterior surgical approach, a lateral surgical approach, or any other surgical approach well known in the art.
Referring to
In one or more alternative embodiments, a surgeon can use a posterior approach or a lateral approach to implant an intervertebral prosthetic device. As such, the patient may be secured in a different position, e.g., in a prone position for a posterior approach or in a lateral decubitus position for a lateral approach.
Moving to block 1402, the location of the affected disc is marked on the patient, e.g., with the aid of fluoroscopy. At block 1404, the surgical area along spinal column is exposed. Further, at block 1406, a surgical retractor system can be installed to keep the surgical field open. For example, the surgical retractor system can be a Medtronic Sofamor Danek Endoring™ Surgical Retractor System.
Proceeding to block 1408, the annulus fibrosus of the affected disc is incised to expose the nucleus pulposus. Further, at block 1410, the nucleus pulposus is removed to create an intervertebral disc space within the annulus fibrosus. At block 1412, the nucleus implant is inserted within the intervertebral disc space of the annulus fibrosus. Further, at block 1414, the expandable core is inflated. At block 1416, the inflated core is aligned. Moving to block 1418, the expandable chamber is inflated, or otherwise expanded, around the inflated core, thereby enabling positioning and retention of the core. Alternatively, the chamber may be inflated before the core.
At block 1420, the first injection tube, i.e., the injection tube attached to the expandable core, can be removed. Continuing to block 1422, the expandable core is sealed—if the expandable chamber is not self-sealing, e.g., with a self-sealing valve. At block 1424, the second injection tube, i.e., the injection tube coupled to the expandable chamber, can be removed. Moreover, at block 1426, the expandable chamber is sealed—if the expandable chamber is not self-sealing, e.g., with a self-sealing valve. At block 1428, the material used to inflate, or expand, the expandable core and the expandable chamber can be cured. In a particular embodiment, the material can be allowed to cure naturally under the ambient conditions of the operating room. Alternatively, the material can be cured using an energy source. For example, the energy source can be a light source that emits visible light, infrared (IR) light, or ultra-violet (UV) light. Further, the energy source can be a heating device, a radiation device, or other mechanical device.
Proceeding to block 1430, the annulus fibrosus is sutured. At block 1432, the intervertebral space can be irrigated. Further, at block 1434, the retractor system can be removed. At block 1436, a drainage, e.g., a retroperitoneal drainage, can be inserted into the wound. Additionally, at block 1438, the surgical wound can be closed. The surgical wound can be closed using sutures, surgical staples, or any other surgical technique well known in the art. Moving to block 1440, postoperative care can be initiated. The method ends at state 1442.
Referring to
As illustrated in
The first expandable chamber 1506 can define an inner surface 1508 and an outer surface 1510. In a particular embodiment, the inner surface 1508 of the first expandable chamber 1506 can be attached to the outer surface 1504 of the expandable core 1502. As such, proper placement of the first expandable chamber 1506 can be based on the placement of the expandable core 1502. Alternatively, the first expandable chamber 1506 can be separate from the expandable core 1502 and the first expandable chamber 1506 may engage the expandable core 1502 after the first expandable chamber 1506 is properly inflated.
As depicted in
The second expandable chamber 1516 can define an inner surface 1518 and an outer surface 1520. In a particular embodiment, the inner surface 1518 of the second expandable chamber 1516 can be attached to the outer surface 1510 of the first expandable chamber 1506 and the inner surface 1508 of the first expandable chamber 1506 can be attached to the outer surface 1504 of the expandable core 1502. Alternatively, the second expandable chamber 1516 can be separate from the first expandable chamber 1506 and the expandable core 1502. In such a configuration, the second expandable chamber 1516 can engage the first expandable chamber 1506 after the first expandable chamber 1506 and the second expandable chamber 1516 are properly inflated. An implant with several chambers may enable more fine adjustment of the position of the core than with a single chamber.
As illustrated in
In a particular embodiment, the nucleus implant 1500 can include a first self-sealing valve (not shown) within the outer surface 1504 of the expandable core 1502, e.g., adjacent to the first injection tube 1512. The nucleus implant 1500 can also include a second self-sealing valve (not shown) within the outer surface 1510 of the first expandable chamber 1506, e.g., adjacent to the second injection tube 1514. Further, the nucleus implant 1500 can include a third self-sealing valve (not shown) within the outer surface 1520 of the second expandable chamber 1516, e.g., adjacent to the third injection tube 1522. The self-sealing valves can prevent the expandable core 1502 and the expandable chambers 1506, 1516 from leaking material after the expandable core 1502 and the expandable chambers 1506, 1516 are inflated and the injection tubes 1512, 1514, 1522 are removed.
In a particular embodiment, the expandable core 1502, the first expandable chamber 1506, and the second expandable chamber 1516 can be inflated so the inner surface 1508 of the first expandable chamber 1506 engages the outer surface of the expandable core 1502 and the outer surface 1510 of the first expandable chamber 1506 engages the inner surface 1518 of the second expandable chamber 1516. Further, the outer surface 1520 of the second expandable chamber 1516 can engage the annulus fibrosis 1604.
The nucleus implant 1500 can provide shock-absorbing characteristics substantially similar to the shock absorbing characteristics provided by the nucleus pulposus. Further, in a particular embodiment, the hardness of the material used to inflate the expandable core 1502 of the nucleus implant 1500 is greater than or equal to the hardness of the material used to inflate the first expandable chamber 1506, i.e., after the materials cure. Moreover, the hardness of the material used to inflate the first expandable chamber 1506 can be greater than or equal to the hardness of the material used to inflate the second expandable chamber 1516, e.g., after those materials cure.
Arranging several expandable chambers around a core may result in an implant with hardness that varies more progressively from the core towards the periphery than with a single chamber. Thus, an implant with a very hard core and a very soft periphery may be obtained. Moreover, an implant with several variable hardness chambers may more easily spread the loads exerted at the vertebral level. In addition, the mobility of the thus arranged implant is better controlled. As one example, the core has a hardness of 55 Shore D, the first chamber has a hardness of 50 Shore D and the second chamber has a hardness of 40 Shore D.
Alternatively, the viscosity of the material used to inflate the expandable core 1502 of the nucleus implant 1500 can be greater than or equal to the viscosity of the material used to inflate the first expandable chamber 1506. Also, the viscosity of the material used to inflate the first expandable chamber 1506 can be greater than or equal to the viscosity of the material used to inflate the second expandable chamber 1516.
Additionally, the height of the expandable core 1502, when expanded, can be greater than or equal to the height of the first expandable chamber 1506 when expanded. Also, the height of the first expandable chamber 1506, when expanded, can be greater than or equal to the height of the second expandable chamber 1516 when expanded. As shown in
In a particular embodiment, the expandable core 1502, the first expandable chamber 1506, the second expandable chamber 1516, or a combination of the expandable core 1502, the first expandable chamber 1506, and the second expandable chamber 1516 of the nucleus implant 1500 can be inflated with one or more injectable extended use approved medical materials that remain elastic after curing. Further, the injectable extended use approved medical materials can include polymer materials that remain elastic after curing.
For example, the polymer materials can include polyurethane materials, polyolefin materials, polyether materials, silicone materials, or a combination thereof. Further, the polyolefin materials can include polypropylene, polyethylene, halogenated polyolefin, flouropolyolefin, or a combination thereof. The polyether materials can include polyetherketone (PEK), polyetheretherketone (PEEK), polyetherketoneketone (PEKK), polyaryletherketone (PAEK), or a combination thereof. Also, the silicone materials can include a silicone hydrogel.
In an alternative embodiment, the injectable extended use approved medical materials can include one or more fluids such as sterile water, saline, or sterile air. In alternative embodiments, the expandable core 1502, the first expandable chamber 1506, the second expandable chamber 1516, or a combination of the expandable core 1502, the first expandable chamber 1506, and the second expandable chamber 1516 of the nucleus implant 1500 can be inflated with one or more of the following: fibroblasts, lipoblasts, chondroblasts, differentiated stem cells or other biologic factor which would create a motion limiting tissue when injected into a bioresorbable motion limiting scaffold.
In a particular embodiment, the nucleus implant 1500 can be installed using a posterior surgical approach, as shown. Further, the nucleus implant 1500 can be installed through a posterior incision 1606 made within the annulus fibrosus 1604 of the intervertebral disc 1600. Alternatively, the nucleus implant 1500 can be installed using an anterior surgical approach, a lateral surgical approach, or any other surgical approach well known in the art.
Referring to
In one or more alternative embodiments, a surgeon can use a posterior approach or a lateral approach to implant an intervertebral prosthetic device. As such, the patient may be secured in a different position, e.g., in a prone position for a posterior approach or in a lateral decubitus position for a lateral approach.
Moving to block 2302, the location of the affected disc is marked on the patient, e.g., with the aid of fluoroscopy. At block 2304, the surgical area along spinal column is exposed. Further, at block 2306, a surgical retractor system can be installed to keep the surgical field open. For example, the surgical retractor system can be a Medtronic Sofamor Danek Endoring™ Surgical Retractor System.
Proceeding to block 2308, the annulus fibrosus of the affected disc is incised to expose the nucleus pulposus. Further, at block 2310, the nucleus pulposus is removed to create an intervertebral disc space within the annulus fibrosus. At block 2312, the nucleus implant is inserted within the intervertebral disc space of the annulus fibrosus. Further, at block 2314, the expandable core is inflated. At block 2316, the inflated core is aligned. Moving to block 2318, the first expandable chamber is inflated, or otherwise expanded, around the inflated core. At block 2320, the second expandable chamber is inflated, or otherwise inflated, around the first expandable chamber.
Proceeding to block 2322, the first injection tube, i.e., the injection tube attached to the expandable core, can be removed. At block 2324, the expandable core is sealed—if the expandable chamber is not self-sealing, e.g., with a self-sealing valve. At block 2326, the second injection tube, i.e., the injection tube coupled to the first expandable chamber, can be removed. Moreover, at block 2328, the first expandable chamber is sealed—if the first expandable chamber is not self-sealing, e.g., with a self-sealing valve. Further, at block 2330, the third injection tube, i.e., the injection tube coupled to the second expandable chamber, can be removed. Moreover, at block 2332, the second expandable chamber is sealed—if the second expandable chamber is not self-sealing, e.g., with a self-sealing valve. At block 2334, the material used to inflate, or expand, the expandable core and the expandable chambers can be cured. In a particular embodiment, the material can be allowed to cure naturally under the ambient conditions of the operating room. Alternatively, the material can be cured using an energy source. For example, the energy source can be a light source that emits visible light, infrared (IR) light, or ultra-violet (UV) light. Further, the energy source can be a heating device, a radiation device, or other mechanical device.
Proceeding to block 2336, the annulus fibrosus is sutured. At block 2338, the intervertebral space can be irrigated. Further, at block 2340, the retractor system can be removed. At block 2342, a drainage, e.g., a retroperitoneal drainage, can be inserted into the wound. Additionally, at block 2344, the surgical wound can be closed. The surgical wound can be closed using sutures, surgical staples, or any other surgical technique well known in the art. Moving to block 2346, postoperative care can be initiated. The method ends at state 2348.
Referring to
As illustrated in
The U-shaped chamber is particularly suited for avoiding the migration of the core towards the incision through which it has been inserted. This is because the U shape partially surrounding the core blocks this incision. This U shape is also advantageous when the intervertebral disc shape has, in a saggital plane, an obvious trapezoidal shape. An intermediate expandable chamber occupying the space between the core 2402 and the U chamber 2406 (
The expandable chamber 2406 can define a first surface 2408 and a second surface 2410. In a particular embodiment, the first surface 2408 of the expandable chamber 2406 can be attached to the outer surface 2404 of the expandable core 2402. As such, proper placement of the expandable chamber 2406 can be based on the placement of the expandable core 2402. Alternatively, the expandable chamber 2406 can be separate from the expandable core 2402 and the expandable chamber 2406 may engage the expandable core 2402 after the expandable chamber 2406 is properly inflated.
As depicted in
In a particular embodiment, the nucleus implant 2400 can include a first self-sealing valve (not shown) within the outer surface 2404 of the expandable core 2402, e.g., adjacent to the first injection tube 2412. Also, the nucleus implant 2400 can include a second self-sealing valve (not shown) within the second surface 2410 of the expandable chamber 2406, e.g., adjacent to the second injection tube 2414. The self-sealing valves can prevent the expandable core 2402 and the expandable chamber 2406 from leaking material after the expandable core 2402 and the expandable chamber 2406 are inflated and the injection tubes 2412, 2414 is removed.
In a particular embodiment, the expandable core 2402 and the expandable chamber 2406 can be inflated so the first surface 2408 of the expandable chamber 2406 engages a portion of the outer surface of the expandable core 2402 and the second surface 2410 of the expandable chamber 2406 engages a portion of the annulus fibrosis 2504. Further, portions of the outer surface 2410 of the expandable chamber 2406 can engage the superior vertebra 2600 and an inferior vertebra 2602. Moreover, when the expandable chamber 2406 is expanded, or otherwise inflated, the expandable chamber 2406 at least partially surrounds the expandable core 2402. As depicted in
The nucleus implant 2400 can provide shock-absorbing characteristics substantially similar to the shock absorbing characteristics provided by the nucleus pulposus. Further, in a particular embodiment, the hardness of the material used to inflate the expandable core 2402 of the nucleus implant 2400 is greater than or equal to the hardness of the material used to inflate the expandable chamber 2406, i.e., after the materials cure. Alternatively, the viscosity of the material used to inflate the expandable core 2402 is greater than or equal to the viscosity of the material used to inflate the expandable chamber 2406.
Also, the overall height of the expandable core 2402 is greater than or equal to the overall height of the expandable chamber 2406 when inflated. As shown in
In a particular embodiment, the expandable core 2402, the expandable chamber 2406, or a combination of the expandable core 2402 and the expandable chamber 2406 of the nucleus implant 2400 can be inflated with one or more injectable extended use approved medical materials that remain elastic after curing. Further, the injectable extended use approved medical materials can include polymer materials that remain elastic after curing.
For example, the polymer materials can include polyurethane materials, polyolefin materials, polyether materials, silicone materials, or a combination thereof. Further, the polyolefin materials can include polypropylene, polyethylene, halogenated polyolefin, flouropolyolefin, or a combination thereof. The polyether materials can include polyetherketone (PEK), polyetheretherketone (PEEK), polyetherketoneketone (PEKK), polyaryletherketone (PAEK), or a combination thereof. Also, the silicone materials can include a silicone hydrogel.
In an alternative embodiment, the injectable extended use approved medical materials can include one or more fluids such as sterile water, saline, or sterile air. In alternative embodiments, the expandable core 2402, the expandable chamber 2406, or a combination of the expandable core 2402 and the expandable chamber 2406 of the nucleus implant 2400 can be inflated with one or more of the following: fibroblasts, lipoblasts, chondroblasts, differentiated stem cells or other biologic factor which would create a motion limiting tissue when injected into a bioresorbable motion limiting scaffold.
The material or materials used for generating the expansion of the core and the chamber can be different for the core and the chamber. This holds true for this or any of the embodiments described herein, particularly when the implant comprises a core and several chambers.
In a particular embodiment, the nucleus implant 2400 can be installed using a posterior surgical approach, as shown. Further, the nucleus implant 2400 can be installed through a posterior incision 2506 made within the annulus fibrosus 2504 of the intervertebral disc 2500. Alternatively, the nucleus implant 2400 can be installed using an anterior surgical approach, a lateral surgical approach, or any other surgical approach well known in the art.
Referring to
In one or more alternative embodiments, a surgeon can use a posterior approach or a lateral approach to implant an intervertebral prosthetic device. As such, the patient may be secured in a different position, e.g., in a prone position for a posterior approach or in a lateral decubitus position for a lateral approach.
Moving to block 2702, the location of the affected disc is marked on the patient, e.g., with the aid of fluoroscopy. At block 2704, the surgical area along spinal column is exposed. Further, at block 2706, a surgical retractor system can be installed to keep the surgical field open. For example, the surgical retractor system can be a Medtronic Sofamor Danek Endoring™ Surgical Retractor System.
Proceeding to block 2708, the annulus fibrosus of the affected disc is incised to expose the nucleus pulposus. Further, at block 2710, the nucleus pulposus is removed to create an intervertebral disc space within the annulus fibrosus. At block 2712, the nucleus implant is inserted within the intervertebral disc space of the annulus fibrosus. Further, at block 2714, the expandable chamber is inflated. Moving to block 2716, the expandable core is inflated, or otherwise expanded, within the inflated expandable chamber.
At block 2718, the first injection tube, i.e., the injection tube attached to the expandable core, can be removed. Continuing to block 2720, the expandable core is sealed—if the expandable chamber is not self-sealing, e.g., with a self-sealing valve. At block 2722, the second injection tube, i.e., the injection tube coupled to the expandable chamber, can be removed. Moreover, at block 2724, the expandable chamber is sealed—if the expandable chamber is not self-sealing, e.g., with a self-sealing valve. At block 2726, the material used to inflate, or expand, the expandable core and the expandable chamber can be cured. In a particular embodiment, the material can be allowed to cure naturally under the ambient conditions of the operating room. Alternatively, the material can be cured using an energy source. For example, the energy source can be a light source that emits visible light, infrared (IR) light, or ultra-violet (UV) light. Further, the energy source can be a heating device, a radiation device, or other mechanical device.
Proceeding to block 2728, the annulus fibrosus is sutured. At block 2730, the intervertebral space can be irrigated. Further, at block 2732, the retractor system can be removed. At block 2734, a drainage, e.g., a retroperitoneal drainage, can be inserted into the wound. Additionally, at block 2736, the surgical wound can be closed. The surgical wound can be closed using sutures, surgical staples, or any other surgical technique well known in the art. Moving to block 2738, postoperative care can be initiated. The method ends at state 2740.
With the configuration of structure described above, the nucleus implant according to one or more of the embodiments provides a device that may be implanted to replace the nucleus pulposus within a natural intervertebral disc that is diseased, degenerated, or otherwise damaged. The nucleus implant can be disposed within an intervertebral disc space that can be established within an intervertebral disc by removing the nucleus pulposus.
The above-disclosed subject matter is to be considered illustrative, and not restrictive, and the appended claims are intended to cover all such modifications, enhancements, and other embodiments that fall within the true spirit and scope of the present invention. Thus, to the maximum extent allowed by law, the scope of the present invention is to be determined by the broadest permissible interpretation of the following claims and their equivalents, and shall not be restricted or limited by the foregoing detailed description.
