Abstract: A lumbar disc prosthesis is provided including a first member with a vertebral disc contact surface and a recessed portion on an opposing surface thereof; a second member with a vertebral disc contact surface and a protruding portion on an opposing surface thereof. The protruding portion of the second member engages with the recessed portion of the first member in use. A facet joint prosthesis is provided, including a first member for attachment to a first posterior lumbar disc in use and a second member for attachment to a second posterior lumbar disc in use, where at least a part of the first member is telescopically mounted in at least a part of the second member in use.

Abstract: A lumbar disc prosthesis is provided including a first member with a vertebral disc contact surface and a recessed portion on an opposing surface thereof; a second member with a vertebral disc contact surface and a protruding portion on an opposing surface thereof. The protruding portion of the second member engages with the recessed portion of the first member in use. A facet joint prosthesis is provided, including a first member for attachment to a first posterior lumbar disc in use and a second member for attachment to a second posterior lumbar disc in use, where at least a part of the first member is telescopically mounted in at least a part of the second member in use.

Abstract: Described herein are various principles for operating a connectionless content unit transfer protocol to transmit content of a content unit to multiple clients using a shared buffer. A server may transfer content of one or more content units to each of multiple clients upon request from the client using individual buffers. For each content unit being transferred, the server may maintain a count of the aggregate size of buffers for transferring content of that content unit. If the server determines that the aggregate size of the buffers transmitting a particular content unit is larger than the content unit itself, the server may establish a shared buffer for transferring that content unit to clients. A server using a shared buffer in this manner may transfer content of the content unit to clients using the shared buffer until all requesting clients have received the content unit.

Abstract: The present invention provides a pedicle screw system, which may include a bone fixation element having an elongate body. The elongate body may include a threaded segment having one or more spiral-oriented grooves, a neck segment adjacent to the threaded segment, and a head segment which is able to receive and/or couple to an orthopedic instrument or implant. The pedicle screw system may further include an anchoring element movably positionable about the bone fixation element. The anchoring element may include one or more elongate teeth which may be slidably positionable into a desired tissue region.

Abstract: Described herein are various principles for operating a connectionless content unit transfer protocol to transmit content of a content unit to multiple clients using a shared buffer. A server may transfer content of one or more content units to each of multiple clients upon request from the client using individual buffers. For each content unit being transferred, the server may maintain a count of the aggregate size of buffers for transferring content of that content unit. If the server determines that the aggregate size of the buffers transmitting a particular content unit is larger than the content unit itself, the server may establish a shared buffer for transferring that content unit to clients. A server using a shared buffer in this manner may transfer content of the content unit to clients using the shared buffer until all requesting clients have received the content unit.

Abstract: Described herein are various principles for operating transfer protocols using adaptive flow control techniques. In accordance with some of these principles, a client may adaptively negotiate with a server regarding a window size to use when communicating datagrams using a connectionless content unit transfer protocol like the Trivial File Transfer Protocol (TFTP). In some implementations, a client may inform a server whether to increase or decrease a window size. In these implementations, the client may increase the window size upon determining that a previous window size has led to successful transfer of content without any loss of datagrams and the client may decrease the window size upon detecting a loss of a datagram. Because of the limited resources available in some environments in which these techniques may be used, in some implementations a window size may be increased by small amounts but may be decreased drastically upon detecting a loss.

Abstract: A lumbar disc prosthesis is provided including a first member with a vertebral disc contact surface and a recessed portion on an opposing surface thereof; a second member with a vertebral disc contact surface and a protruding portion on an opposing surface thereof. The protruding portion of the second member engages with the recessed portion of the first member in use. A facet joint prosthesis is provided, including a first member for attachment to a first posterior lumbar disc in use and a second member for attachment to a second posterior lumbar disc in use, where at least a part of the first member is telescopically mounted in at least a part of the second member in use.

Abstract: A lumbar disc prosthesis is provided including a first member with a vertebral disc contact surface and a recessed portion on an opposing surface thereof; a second member with a vertebral disc contact surface and a protruding portion on an opposing surface thereof. The protruding portion of the second member engages with the recessed portion of the first member in use. A facet joint prosthesis is provided, including a first member for attachment to a first posterior lumbar disc in use and a second member for attachment to a second posterior lumbar disc in use, where at least a part of the first member is telescopically mounted in at least a part of the second member in use.

Abstract: The present invention provides a dynamic stabilization device positionable about a portion of a spinal column. The stabilization device may generally include a first component and a second component, where the first and second components are movably coupled to one another to define an arcuate path of motion. The stabilization device may also include one or more adjustment elements positionable within first and second adjustment openings to affect the path of motion between the first and second components and/or the behavior and characteristics of the movement. In addition, one or more resistive elements may be adjustably positionable within either and/or both of the first and second adjustment openings to provide resistance and/or dampening of the forces experienced as the first and second components move relative to one another. The stabilization device may further define a joint having three degrees of freedom to adapt to movement of a spinal column.

Abstract: A system and method for lumbar arthroplasty in a spinal segment is provided having first and second vertebral bodies, where a intervertebral disc prosthesis may be positioned between the first and second vertebral bodies such that a center of rotation of movement of the vertebral bodies about the prosthesis is located substantially proximate to the upper endplate of the second vertebral body and substantially proximate to the posterior one-third portion of the second vertebral body. In addition, a stabilization element may be affixed to the first and second vertebral bodies such that a range of motion of the stabilization device defines a center of rotation substantially proximate to that of the intervertebral disc prosthesis.

Abstract: The present invention provides a surgical instrument system including a first instrument defining a track extending along a length thereof, a second instrument releasably engageable with a prosthesis and having an engagement structure slidably engageable with the track of the first instrument, a third instrument having a cutting element and an engagement structure slidably engageable with the track of the first instrument, and a fourth instrument having a prosthesis trial element sized and shaped substantially similar to the prosthesis, and including an engagement structure slidably engageable with the track of the first instrument.

Abstract: The present invention provides a dynamic stabilization device positionable about a portion of a spinal column. The stabilization device may generally include a first component and a second component, where the first and second components are movably coupled to one another to define an arcuate path of motion. The stabilization device may also include one or more adjustment elements positionable within first and second adjustment openings to affect the path of motion between the first and second components and/or the behavior and characteristics of the movement. In addition, one or more resistive elements may be adjustably positionable within either and/or both of the first and second adjustment openings to provide resistance and/or dampening of the forces experienced as the first and second components move relative to one another. The stabilization device may further define a joint having three degrees of freedom to adapt to movement of a spinal column.

Abstract: The present invention provides a dynamic stabilization device positionable about a portion of a spinal column. The stabilization device may generally include a first component and a second component, where the first and second components are movably coupled to one another to define an arcuate path of motion. The stabilization device may also include one or more adjustment elements positionable within first and second adjustment openings to affect the path of motion between the first and second components and/or the behavior and characteristics of the movement. In addition, one or more resistive elements may be adjustably positionable within either and/or both of the first and second adjustment openings to provide resistance and/or dampening of the forces experienced as the first and second components move relative to one another. The stabilization device may further define a joint having three degrees of freedom to adapt to movement of a spinal column.

Abstract: Lumbar disc and facet joint replacement prosthesis are provided. The lumbar disc prosthesis includes first member having a vertebral disc contact surface and a recessed portion on an opposing surface thereof and a second member having a vertebral disc contact surface and a protruding portion on an opposing surface thereof. The protruding portion of the second member engages the recessed portion of the first member in use. The first and second members are provided with at least a middle section and two end sections. The recessed and protruding portions are provided in the middle section of the respective members and each end section has a narrowing taper. The facet joint prosthesis includes a first member for attachment to a first posterior lumbar disc and a second member for attachment to a second posterior lumbar disc. At least a part of the first member is telescopically mounted in at least a part of the second member.

Abstract: The present invention provides a pedicle screw system, which may include a bone fixation element having an elongate body. The elongate body may include a threaded segment having one or more spiral-oriented grooves, a neck segment adjacent to the threaded segment, and a head segment which is able to receive and/or couple to an orthopedic instrument or implant. The pedicle screw system may further include an anchoring element movably positionable about the bone fixation element. The anchoring element may include one or more elongate teeth which may be slidably positionable into a desired tissue region.

Abstract: The present invention provides a system and method for lumbar arthroplasty in a spinal segment having first and second vertebral bodies, where a intervertebral disc prosthesis may be provided and positioned between the first and second vertebral bodies such that a center of rotation of movement of the vertebral bodies about the prosthesis is located substantially proximate to the upper endplate of the second vertebral body and substantially proximate to the posterior one-third portion of the second vertebral body. In addition, a stabilization element may be affixed to the first and second vertebral bodies such that a range of motion of the stabilization device defines a center of rotation substantially proximate to that of the intervertebral disc prosthesis.