Abstract: An artificial joint or disc replacement (ADR) broadly includes a pair of opposing endplate components, each attached to one of the upper and lower vertebrae, a cushioning component disposed between the endplate components, and a mechanism for coupling the cushioning component to one or both of the endplates. In the preferred embodiment, the cushioning component takes the form of a tire-like outer structure attached to an inner hub. A filler material is also preferably contained within the cushioning component. The filler material may be a gas, liquid, foam, or gel, including a hydrogel. One or both of the endplate components may include a modified surface to increase adherence to respective opposing bone surfaces.

Abstract: Artificial disc replacement (ADR) systems with intradiscal components feature non anterior-posterior (A-P) or oblique-oriented keels such that the great vessels do not require as much retraction during insertion. The system may further include guides for aligning the ADR prior to insertion, and for cutting an oblique slot into a vertebral endplate to receive the keel. A screw adapted to penetrate a vertebral body may be used in conjunction with the keel. The screw and keel may converge, diverge or intersect. The screw may further include a mechanism providing a locking relationship with the keel. The system may further including a guide to direct drill bits and screws through holes in the keel. ADRs according to the invention may additionally, independently include a non-symmetrical endplate shaped so as to decrease the risk of injuring the great vessels.

Abstract: Artificial disc replacements (ADRs) use articulating components to permit normal spinal movement(s). According to the invention, an ADR situated between upper and lower vertebral bodies comprises a first endplate affixed to one of the vertebral bodies providing a first articulating surface having a first radius of curvature, a second endplate affixed to the other one of the vertebral bodies providing a second articulating surface having a second radius of curvature which is different from the first radius of curvature, and a spacer component having opposing surfaces that cooperate with the first and second articulating surfaces. In the preferred embodiment, the first endplate is affixed to the upper vertebral body, the first articulating surface is concave, the second endplate is affixed to the lower vertebral body, the second articulating surface is convex, and the first radius of curvature is larger than the second radius of curvature.

Abstract: Surgical implants are configured for placement posteriorly to a spinal canal between vertebral bodies to distract the spine and enlarge the spinal canal. In the preferred embodiments the device permits spinal flexion while limiting spinal extension, thereby providing an effective treatment for treating spinal stenosis without the need for laminectomy. The invention may be used in the cervical, thoracic, or lumbar spine. Numerous embodiments are disclosed, including elongated, length-adjustable components coupled to adjacent vertebral bodies using pedicle screws. The preferred embodiments, however, teach a device configured for placement between adjacent vertebral bodies and adapted to fuse to the lamina, facet, spinous process or other posterior elements of a single vertebra. Various mechanisms, including shape, porosity, tethers, and bone-growth promoting substances may be used to enhance fusion. The tether may be a wire, cable, suture, or other single or multi-filament member.

Abstract: Arthroplasty devices having improved bone in growth to provide a more secure connection within the body. Different embodiments disclosed include devices having threaded intramedullary components, devices configured to receive bone growth promoting substances, devices with resorbable components, and devices configured to reduce shear stress.

Abstract: A surgical fixation system including a surgical fixation plate, a plurality of fasteners, and a retainer having an improved mechanism to prevent the back out of screws employed in securing a surgical fixation plate to an intended orthopedic location.

Abstract: Numerous joint replacement implant embodiments including a total knee replacement implant including a femoral component (102) having a wheel (104); and a tibial component (106) including a shock-adsorbing component with a piston assembly (110) and spring (112). Said implants contain a cushioning or shock-absorbing member to dampen axial loads and other forces. In many embodiments, fluid is force rapidly from the device wherein compression and dampening is achieved by valves or other pathways that allow for a slower return of the fluid back into the implant as the pressure is relieved.

Abstract: This invention is directed to improved methods and devices to attach arthroplasty devices, particularly the spine, distract the disc space, machine the disc space to improve the fit between ADRs and the vertebrae, to hold and remove ADRs, and to facilitate spinal fusion for a failed ADR surgery. One aspect of the invention places anchor devices in the spine during a first operation. Spinal devices are connected to the anchoring devices during a second procedure. The second procedure is generally performed months after the insertion of the anchoring devices. The time between the two procedures allows bone to grow into the anchoring devices. Minimal forces are exerted on the anchoring devices between the procedures. Other embodiments are described where a previously implanted ADR having a pair of opposing endplates is immobilized using a device the attached to the endplates, fits between the endplates, or both.

Abstract: Improved methods and apparatus render ADR insertion safer and more precise. Certain surgical instruments according to the invention include a level enabling a user to align the instrument for proper placement of a surgical implant. A different surgical instrument includes two or more scopes mounted relative to the instrument permitting a user to simultaneously view more than one side of the instrument. A device for use with a surgical instrument having a long shaft includes a holder that surrounds at least a portion of the shaft allowing a user to control the instrument with both hands. A further surgical instrument comprises a set of retractors and one or more guards placed over the retractors for protecting the great vessels, nerves or other delicate structures during a surgical procedure.

Abstract: Artificial disc replacement (ADR) components cooperate to limit axial rotation and/or lateral bending to a greater degree when the spine is extended than when the spine is a neutral to flexed position, thereby decreasing loads placed upon the facet joints. In the preferred embodiment, truncated articulating surfaces with non-articulating side surfaces allow increasing amounts of axial rotation and lateral bending as the total disc replacement (TDR) moves from full extension to full flexion. Limiting axial rotation and lateral bending of the TDR protects the facet joints and the Annulus Fibrosus, since the facet joints carry more load when the spine is extended than when the spine is flexed. Thus the invention serves to protect the facet joints while allowing normal or near-normal spinal motion.

Abstract: Disc spacers (DS) are assembled within a disc space, allowing them to be inserted through smaller openings in the Annulus Fibrosus (AF). The large size of the assembled DS decreases the pressure on the vertebral endplates. Embodiments of the invention may be used in the cervical, thoracic, or lumbar spine. The DS may be inserted through an anterior, lateral, or posterior approach to the spine using annulus preserving techniques. The devices are preferably made of biocompatible materials such as titanium, chrome cobalt, and ceramic. Alternative materials, including materials with shape memory properties, such as Nitinol, may be used to form one or more components of the device.

Abstract: Arthroplasty devices having improved bone in growth to provide a more secure connection within the body. Different embodiments disclosed include devices having threaded intramedullary components, devices configured to receive bone growth promoting substances, devices with resorbable components, and devices configured to reduce shear stress.

Abstract: This invention resides in an apparatus for inhibiting full extension between upper and lower vertebral bodies, thereby preventing pain and other complications associated with spinal movement. In the preferred embodiment, the invention provides a generally transverse member extending between the spinous processes and lamina of the upper and lower vertebral bodies, thereby inhibiting full extension. Various embodiments of the invention may limit spinal flexion, rotation and/or lateral bending while preventing spinal extension. In the preferred embodiment, the transverse member is fixed between two opposing points on the lower vertebral body using pedicle screws, and a cushioning sleeve is used as a protective cover. The transverse member may be a rod or cable, and the apparatus may be used with a partial or full artificial disc replacement. To control spinal flexion, rotation and/or lateral bending one or more links may be fastened to an adjacent vertebral body, also preferably using a pedicle screw.

Abstract: Improved techniques are disclosed for preparing a disc space to accept an intradiscal device. Methods and apparatus are described to quickly remove disc tissue and improve the surface contact between intradiscal devices and the vertebral end plates (VEP)s. The invention also anticipates the use of navigational devices and CNC controlled machines or robotic arms in conjunction with the disclosed methods and apparatus. The various instruments may be used to remove disc material and/or shape the VEPs. Kits may be supplied with various sizes and shapes of the devices to accommodate discs of different sizes and shapes.

Abstract: Spacerless artificial disc replacements (ADR) are disclosed. One preferred embodiment includes two saddle-shaped components to facilitate more normal spinal flexion, extension, and lateral bending while limit axial rotation, thereby protecting the facet joints and the annulus fibrosus (AF). Either or both of the superior and inferior components are made of a hard material such as chrome cobalt, titanium, or a ceramic including alumina, zirconia, or calcium phosphate. The articulating surfaces of the ADR are also preferably highly polished to reduce friction between the components. Metals, alloys or other materials with shape-memory characteristics may also prove beneficial.

Abstract: A device and method are used in fortifying an intervertebral disc having an annulus fibrosis with an inner wall. According to the method, a hole is formed through the annulus fibrosis, and a collapsed bag is inserted into the disc through the hole. The bag is inflated, or allowed to expand within the disc space, then filling with one or more biocompatible materials. The hole in the annulus fibrosis is then closed. In one preferred embodiment, the bag includes an inflatable bladder or balloon which is filled with a gas or liquid to expand the bag. In an alternative preferred embodiment, the bag includes a self-expanding frame that assumes a collapsed state for introduction into the disc space and an expanded state once inserted through the hole in the annulus. The self-expanding frame is composed of a shape-memory material, for example.

Abstract: Artificial disc replacements (ADRS) are configured for implantation using a lateral, anterior-lateral, or posterior-lateral approach. A first component having a first segment resides in the disc space for articulation purposes, with a second segment adapted for fixation to the lateral outer surface of one of the vertebral bodies. A second component having a first segment resides in the disc space for articulation purposes, with a second segment adapted for fixation to the lateral outer surface of the other vertebral body. The first segments of the two components may articulate against one another without a spacer, or a spacer forming a mobile bearing may be disposed between the first segments of the two components. In the preferred embodiment, one or both of the two components are in the form of bent plates such that the second segment is positioned against a lateral wall for fixation. In the preferred embodiment, screws are used through the second segment and into a vertebral body.

Abstract: A vertebral shock absorber in the form of an elongated compressible member having two ends, one fastened to an upper vertebra, and the other fastened to a lower vertebra. The elongated member may be fastened using pedicle screws or by way of ball-and-socket joints for enhanced range of motion. In the preferred embodiment, the elongated compressible member is constructed using telescoping sleeves to create a cavity wherein there is disposed a compressible, resilient component such as a spring, elastomeric material, liquid, gel, hydrogel, or other suitable substance. The shock absorber may be combined with an intradiscal component and/or one or more plates that extends at least partially onto a vertebral endplate to facilitate lateral application.

Abstract: The invention broadly facilitates reconstruction of the Annulus Fibrosus (AF) or the AF and the Nucleus Pulposus (NP). Such Reconstruction prevents recurrent herniation following Microlumbar Discectomy (MLD) other procedures. The invention may also be used in the treatment of herniated discs, annular tears of the disc, or disc degeneration, while enabling surgeons to preserve the contained NP. The methods and apparatus may be used to treat discs throughout the spine including the cervical, thoracic, and lumbar spines of humans and animals. In the preferred embodiment, a spinal repair system according to the invention comprises a first end portion adapted for placement within an intervertebral body, a second end portion adapted for placement within an adjacent intervertebral body, and a bridge portion connecting the first and second end portions, the bridge portion being adapted to span a portion of an intervertebral disc space and prevent excessive outward bulging.

Abstract: This invention improves upon prior aft total disc replacements (TDRs) by more closely replicating the kinematics of a natural disc. The preferred embodiments feature two or more fixed centers of rotation (CORs) and an optional variable COR (VCOR) as the artificial disk replacement (ADR) translates from a fixed posterior COR that lies posterior to the COR of the TDR to facilitate normal disc motion. The use of two or more CORs allows more flexion and more extension than permitted by the facet joints and the artificial facet (AF). AF joint-like components may also be incorporated into the design to restrict excessive translation, rotation, and/or lateral bending.