A vertebral column correction system for correcting a spinal deformity without fusing the joint segments is disclosed. The vertebral column correction system may have first and second vertebral anchors secured to first and second vertebrae. The vertebral column correction system may further comprise one or more intermediate vertebral anchors secured to vertebrae between the first and second vertebrae. A connection member may be disposed within a head portion of the vertebral anchors. At least a portion of the connection member may be a flexible member, such as a flexible cord, configured for tensioning between at least two vertebral anchors for providing a desired amount of tension to apply a correctional force to the spinal column. A spring member, or other tensioning member, may maintain the tension of the connection member.

A medical device includes a first elongate member defining an interior region and configured to be coupled to a first anatomical structure within a body and a second elongate member configured to be coupled to a second anatomical structure within the body. A portion of the second elongate member is configured to be disposed within the interior region. The first and second elongate members collectively have a first configuration in which they collectively have a first length when the portion of the second elongate member is disposed within the interior region of the first elongate member. When coupled to the first and second anatomical structures, the first and second elongate members can be moved to a second configuration in which they collectively have a second length different than the first length.

A bone anchor implant assembly configured for surgical implantation into a bone of a patient. The bone anchor implant assembly includes an elongate rod, a separate shank and head, and a closure mechanism configured as a one-part closure or two-part closure. The one-part closure and two-part closure are configured to be interchangeable with each other for closing a channel of the head and locking the assembly and the elongate rod between arms of the head with the closure mechanism.

A pivotal bone anchor assembly includes a receiver having central bore with a partially spherical engagement surface adjacent a lower opening, and a shank having a capture portion at a proximal end that is uploadable into the central bore of the receiver through the lower opening. The assembly also includes a retainer comprising a compressible, open ring-shaped body having at least a slit or missing section, a center opening, and an outer partially spherical surface configured for pivotal engagement with the partially spherical engagement surface of the receiver. The assembly further includes an insert comprising a center aperture configured to provide access to the internal drive socket for the drive tool, an upper surface configured to engage the fixation rod, and a lower surface configured to transfer the downwardly-directed force toward the capture portion of the shank to lock the assembly.

Devices and systems can be used to treating spinal conditions. For example, this document describes artificial facet joint systems that can be implanted to treat spinal conditions while facilitating normal stability and motions of the spine. Such systems and methods can be used to treat spinal conditions such as, but not limited to, spondylosis, vertebral fractures, and the like.

A dynamic fixation medical implant includes a longitudinal connecting member assembly having an elongate coil-like outer member and an inner cylindrical core attached to the outer member at only one end thereof. Some assemblies include a second longitudinal connecting member in the form of a rod that is fixed to the inner core and extends outwardly from the assembly. Certain assemblies include a threaded core or threaded inserts that cooperate with a helical slit of the coil-like outer member. Two or more cooperating bone screw assemblies attach to the connecting member assembly. The bone screw assemblies may include upper and lower compression members for affixing to and cradling the coil-like outer member only, allowing relative movement between the outer member and the inner cylindrical core. Press fit or snap-on features attach one end of the coil-like outer member to one end of the inner cylindrical core.

A bone anchor implant assembly configured for surgical implantation into a bone of a patient. The bone anchor implant assembly includes an elongate rod, a separate shank and head, and a closure mechanism configured as a one-part closure or two-part closure. The one-part closure and two-part closure are configured to be interchangeable with each other for closing a channel of the head and locking the assembly and the elongate rod between arms of the head with the closure mechanism.

A method for locking an elongate rod within a head of a bone anchor implant assembly that is configured for surgical implantation into a bone of a patient. The method includes providing an elongate rod, providing a separate shank and the head, and providing a closure mechanism configured as a one-part closure or two-part closure. The method further includes receiving the elongate rod in the channel and closing the channel with the closure mechanism. The one-part closure and two-part closure are configured to be interchangeable with each other for closing a channel of the head and locking the assembly and the elongate rod between arms of the head with the closure mechanism.

A pivotal bone screw assembly includes a receiver having a central bore with a bottom opening and a channel for receiving an elongate rod, with the central bore including a partial spherical internal surface adjacent the bottom opening and a horizontally-extending recess with a cylindrical sidewall surface. The assembly also includes a shank with a capture structure for positioning within the central bore and an anchor portion for attachment to the bone, with the capture structure having a partial spherical lower surface configured to slidably engage the internal surface of the central bore to provide for pivotal motion of the shank with respect to the receiver, together with an insert with a rod seating surface and an outwardly-projecting radiused structure, with the insert being downwardly displaceable within the central bore until the radiused structure snaps into the recess to prevent upward movement of the insert with respect to the receiver.

A vertebral column correction system for correcting a spinal deformity without fusing the joint segments is disclosed. The vertebral column correction system may have first and second vertebral anchors secured to first and second vertebrae. The vertebral column correction system may further comprise one or more intermediate vertebral anchors secured to vertebrae between the first and second vertebrae. A connection member may be disposed within a head portion of the vertebral anchors. At least a portion of the connection member may be a flexible member, such as a flexible cord, configured for tensioning between at least two vertebral anchors for providing a desired amount of tension to apply a correctional force to the spinal column. A spring member, or other tensioning member, may maintain the tension of the connection member.