A soft dynamic stabilization assembly includes a core, typically in the form of a tensioned cord, at least one pair of bone anchors, a spacer surrounding the core located between the bone anchors, typically, at least one elastic bumper and at least one fixing or blocking member. The core is slidable with respect to at least one of the bone anchors and cooperating spacer.

A facet joint replacement system includes a facet joint replacement device including an enclosing body and an articulating body. The enclosing body includes an interior surface defining an inner cavity of the enclosing body. The interior surface includes a first articulating surface and a projection extending inwardly relative to a surrounding area of the interior surface. The articulating body is positioned within the inner cavity of the enclosing body and is configured to move within the enclosing body. The articulating body includes a second articulating surface and a recess extending inwardly relative to a surrounding area of the articulating body and aligned with the projection of the interior surface of the enclosing body so as to allow movement of the projection along the recess of the enclosing body while constraining rotational motion of the articulating body within the enclosing body.

A pivotal bone anchor assembly for securing an elongate rod to a bone of a patient. The assembly includes a receiver having pair of upright arms that define an open channel configured to receive the elongate rod and a discontinuous helically wound receiver guide and advancement structure formed into the interior surfaces of the upright arms. The assembly further includes a closure configured for positioning within the open channel to secure the elongate rod to the receiver in a locked configuration, with the closure having an outer surface with a mating continuous helically wound closure guide and advancement structure configured to resist a tendency toward splaying between the upright arms upon a screwing in of the closure within the open channel by rotatable engagement with the receiver guide and advancement structure.

A receiver assembly for securing an elongate rod to a bone anchor includes a receiver having pair of upright arms that define an open channel configured to receive the elongate rod, a discontinuous helically wound receiver guide and advancement structure formed into the interior surfaces of the upright arms, and horizontally-elongated tool engaging grooves formed into upper portions of the outer surface of the upright arms. The receiver assembly further includes a closure configured for positioning within the open channel to secure the elongate rod to the receiver in a locked configuration, with the closure having an outer surface with a mating continuous helically wound closure guide and advancement structure configured to resist a tendency toward splaying between the upright arms upon a screwing in of the closure within the open channel by rotatable engagement with the receiver guide and advancement structure.

An implantable, elongated fixation rod that, when coupled to a spinal column in a living patient, stabilizes a portion of the spinal column. The elongated fixation rod includes a plurality of different rod regions formed from surgical stainless steel that are aligned along a longitudinal axis of the elongated fixation rod. The different rod regions include different dimensions tailored to provide the different rod regions with different rigidities specific to support regions of the spinal column where the elongated fixation rod is to be installed. A smooth transition region at least 5 mm in length is integrally formed as part of a common monolithic structure with the different rod regions, and is devoid of a full, sharp step that forms a 90° angle relative to the longitudinal axis of the elongated fixation rod and separates the different rod regions along the longitudinal axis of the fixation rod.

A distraction system includes a distraction rod having one end configured for affixation to at a first location on patient. The system further includes an adjustable portion configured for placement in the patient at a second location, the adjustable portion comprising a housing containing a magnetic assembly comprising a magnet, the magnetic assembly secured to a threaded element that interfaces with an opposing end of the distraction rod. The system includes a magnetically permeable member in proximity to the magnetic assembly and covering an arc of less than 360° of the adjustable portion.

A system for spinal fixation with a non-rigid portion at least one of the caudal or cephalad terminus. Various devices and techniques are described for transition from a rigid fixation construct to a less rigid support structure applied to a “soft zone” that helps share the stress created on the spinal levels caused by the fixed levels below. In some embodiments, the soft zone is provided by terminating the construct with one of a flexible tether or a dampening rod.

A system for moving a portion of a patient's body including a housing having a first cavity extending along a longitudinal axis, a first distraction rod having a proximal end and a distal end, the first distraction rod and the housing being telescopically displaceable with respect to each other along the longitudinal axis, the first distraction rod having a cavity extending along the longitudinal axis, a second distraction rod having a proximal end and a distal end and configured to be telescopically displaceable from within the second cavity along the longitudinal axis, and a drive system configured to move the first distraction rod in relation to the housing and to move the second distraction rod in relation to the first distraction rod.

Connector assemblies, systems, and methods thereof. A modular connector has a first end that clamps to a first rod in an existing construct and a second end having a modular connection point configured to connect a second rod in a new construct such that the new construct can be extended from the existing construct.

A spinal construct includes an existing spinal rod implant defining a rod dimension and having at least one mating surface. At least one extension includes a mating surface engageable with the at least one mating surface of the existing spinal rod implant to comprise a connection having a dimension the same as the rod dimension. A coupling member is configured to fix the existing spinal rod implant with the at least one extension. Systems, surgical instruments, implants and methods are disclosed.