Abstract: A spinal rod anchoring device is disclosed comprising a body comprising a distal end and a proximal end, wherein a threaded bone anchor is positioned toward the distal end, and a U-shaped head portion is positioned toward the proximal end. The head portion and the threaded bone anchor are fixedly attached. The spinal rod anchoring device also comprises a saddle comprising a concave interior region wherein the interior region has an open channel. The saddle is moveably seated within the base of the head portion, and a spinal connection element is disposed on the saddle. The spinal rod anchoring device further comprises a retaining pin configured to be inserted through the channel in the saddle and secured in a groove, wherein the groove is centrally positioned within the head portion, wherein the retaining pin secures the saddle to the head portion.

Abstract: A pivotal bone anchor assembly includes a receiver having a central bore with a spherical seating surface adjacent a bottom opening and upright arms defining a channel for receiving a rod. The upright arms include side outer surfaces with horizontal tool engagement grooves spaced below top surfaces and having downwardly-facing upper groove surfaces and upwardly-facing lower groove surfaces that extend to front and back planar surface portions of the upright arms. The upright arms also include vertical tool engagement slots extending into and downward across the side outer surfaces from the top surfaces through to at least the upper groove surfaces of the horizontal tool engagement grooves. The assembly also includes a shank having an anchor portion for attachment to patient bone and a capture portion with a curvate lower surface configured for slidable engagement with the spherical seating surface of the receiver prior to locking the assembly with a closure.

Abstract: A bone fixation assembly is disclosed. The bone fixation assembly may include a bone fixation plate including a fastener hole and a cavity adjacent to the fastener hole. The bone fixation assembly may also include a clip. The clip may include a body having a partial circular shape, the body positioned at least partially in the cavity. The clip may further include a plurality of tabs extending inward relative to the partial circular shape of the body, each tab having a convex shape extending inward relative to the partial circular shape of the body, wherein the body and the plurality of tabs are positioned below a top surface of the bone fixation plate.

Abstract: This disclosure presents a polyaxial pedicle screw system. The system may comprise one or more of a screw body, a screw insert, a head component, a bushing, and/or other components. The screw body may have a major diameter. The screw insert may comprise a spherical head having a head diameter. The head component may have an axial bore forming an interior surface which defines a bore diameter of the axial bore. The interior surface may define a narrowest part of the bore diameter of the axial bore at a first end of the head component. The head diameter of the spherical head of the screw insert and/or the major diameter of the screw body may be larger than the narrowest part of bore diameter of the axial bore.

Abstract: Pedicle-based intradiscal fixation devices, systems, instruments, and methods thereof. The implant or a portion thereof may be composed of a shape-memory material, which has a curved shape-memory orientation and a temporarily straight orientation. The implant may be configured to be inserted into a pedicle of an inferior vertebra, through the vertebral body of the inferior vertebra, and into the vertebral body of the superior vertebra to thereby stabilize the inferior and superior vertebrae.

Abstract: A pivotal bone anchor assembly includes a bone screw comprising a screw head and an anchor portion, and a receiver comprising a base defining a central bore and an upper portion defining a first channel, with the central bore extending upward through the first channel to a top of the receiver. The assembly also includes an open ring retainer with a gap that is uploadable into a lower portion of the central bore through a bottom opening for capturing the screw head within receiver, and an insert positionable into the central bore above the screw head with upright arms defining a second channel and opposite extensions extending radially outward into the first channel body for blocking rotation of the insert within the receiver.

Abstract: A bone fastener comprises a first member defining a plurality of grooves. A coupling member is disposed with the first member. A first band and a second band are disposable within the grooves. A second member is configured to penetrate tissue and includes a head engageable with the first band to provisionally connect the first member to the second member. The coupling member is engageable with a part to move the part relative to the first member into engagement with the second band to dispose the second band adjacent the first band to connect the first member to the second member. Systems, surgical instruments, implants and methods are disclosed.

Abstract: The present invention is an implant for bone. The current implant is particularly useful in spinal surgical procedures.

Abstract: Various exemplary methods and devices are provided for fixing bone anchors to bone. In general, the methods and devices can allow for a bone anchor to be fixed to a bone at a desired angle to a receiver member. In an exemplary embodiment, a bone anchor assembly is provided that includes a bone anchor configured to engage bone, a receiver member that seats a spherical head of the bone anchor and a spinal fixation element, a compression member seated within the receiver member, proximally of the head of the bone anchor, and a closure mechanism seated within the receiver member, proximally of the compression member. One or more of the receiver member, the compression member, and the closure mechanism can have gripping features thereon configured to secure the bone anchor and/or the spinal fixation element within the receiver member, thereby reducing a risk of slippage of the bone anchor and/or the spinal fixation element with respect to the receiver member.

Abstract: A bone fastener comprises a first member comprising a first surface defining an implant cavity. The first member includes a first part being non-rotatable relative to the first surface and a second part including a second surface defining a portion of the implant cavity and a slot. A second member is configured to penetrate tissue and is connectable with the first member. The first member is rotatable relative to the second member in a first plane of a body and the second part is movable relative to the first part in a second plane of the body such that the first part is relatively translatable in the slot. Implants, systems, instruments and methods are disclosed.

Abstract: A bone screw has a first portion including a head. A second portion includes a threaded shaft having a length and a major diameter. The shaft includes a length-to-major diameter ratio of less than about 2.0. The thread has a minor diameter and includes a major-diameter-to-minor diameter ratio of greater than about 2.0. The shaft further has at least one thread including a pitch of greater than about 1.0 mm and defining a pitch cavity for disposal of tissue. Systems and methods of use are disclosed.

Abstract: A coupling device includes a first coupling body configured to be coupled to a first bone anchor, a second coupling body configured to be coupled a second bone anchor, and a connection device comprising a first connection member connectable to the first coupling body, a second connection member connectable to the second coupling body, and a length adjustment member positionable between and insertable at least partially into each of the first and second connection members. The first and second connection members are movable relative to the length adjustment member. The length adjustment member can be actuated in a first direction to increase a distance between the first connection member and the second connection member, and in a second direction different from the first direction to decrease the distance between the first connection member and the second connection member.

Abstract: A hinged bone screw and tool set is used for implanting such bone screws in a human spine, followed by the implantation of a longitudinal connecting member into the bone screws. The hinged bone screw includes a shank with an upper portion and a receiver with integral arms forming a U-shaped channel. A lower curved seat partially defining the U-shaped channel cooperates with an upper portion of the bone screw shank for hinged movement of the shank with respect to the receiver. The tool set includes an insertion tool, a bone screw driver, a reduction tool and a closure starter. The insertion tool includes a bone screw attachment structure and a laterally opening channel. The insertion tool further includes a threaded portion for cooperation with the reduction tool to provide synchronized placement of a closure structure in the bone screw receiver while reducing and capturing a longitudinal connecting member within the receiver.

Abstract: A spinal construct includes a coupling member including a first mating surface engageable with an existing fastener implant. The existing fastener implant being connected with an existing spinal rod implant. A connector is engageable with the existing fastener implant and has a rod extending therefrom. A locking member is engageable with a second mating surface of the coupling member. Systems, surgical instruments, implants and methods are disclosed.

Abstract: A pivotal bone screw assembly includes a threaded shank body having an integral upper portion receivable in a receiver, the receiver having an upper channel for receiving a longitudinal connecting member and a lower cavity cooperating with a lower opening. The shank upper portion expands a retaining member in the receiver cavity to capture the shank upper portion in the receiver. The retaining member and attached shank are pivotable with respect to the receiver until locked in place with respect to the receiver. A pre-assembled receiver, retaining member and compression insert may be popped-on or snapped-on to the shank upper portion prior to or after implantation of the shank into a vertebra.

Abstract: A medical implant assembly includes a polyaxial bone anchor having a shank, a receiver, a lower compression insert with surfaces for closely receiving an elongate connecting member and a dual closure structure that may include a single flange or helical flange. The dual closure structure independently engages the connecting member and the lower compression insert. A threaded capture connection of the bone anchor includes a shank upper surface exclusively engaging the lower compression insert and a retainer threadably attached to the shank and spaced from the upper surface, the retainer configured for polyaxial motion with respect to the receiver prior to locking.

Abstract: A device (1) for fixating a rod (10) on a bone with a tulip, with a pedicle screw (2) and with a tightening screw (5). The rod clamp (6) is pivotable to the tightening screw and can follow transverse motions of the rod (10). This increases the stability of the entire structure, particularly in the application in spine surgery.

Abstract: A spinal stabilization assembly includes a first hook assembly, a second hook assembly, and a connector member. The first hook assembly has a receiver and a hook member that extends from the receiver. The receiver defines a rod-receiving slot configured to receive a spinal rod. The hook member defines an aperture and includes a hook. The aperture is supported between the rod-receiving slot and the hook. The connector member is secured to the second hook assembly and receivable in the aperture of the first hook assembly to couple the first and second hook assemblies together.

Abstract: A medical implant assembly includes a polyaxial bone anchor having a shank, a receiver, a lower compression insert with surfaces for closely receiving an elongate connecting member and a dual closure structure that may include a single flange or helical flange. The dual closure structure independently engages the connecting member and the lower compression insert. A threaded capture connection of the bone anchor includes a shank upper surface exclusively engaging the lower compression insert and a retainer threadably attached to the shank and spaced from the upper surface, the retainer configured for polyaxial motion with respect to the receiver prior to locking.

Abstract: A coupling assembly for coupling a rod to a bone anchoring element is provided, wherein the coupling assembly includes a receiving part having a first end, a second end, a central axis extending through the first end and second end, an accommodation space for accommodating a head of an anchoring element, a bore extending from the accommodation space to the first end, and a recess for receiving a rod. The accommodation space has an opening at the second end sized to permit insertion of a head of the bone anchoring element. The coupling assembly further includes a retainer element configured to be positioned at least partially in the accommodation space and being radially expandable and/or compressible to allow retaining a head inserted through the opening. The retainer element is held in position adjacent the opening by an engagement structure provided at or in the accommodation space.

Abstract: A medical implant assembly includes a polyaxial bone anchor having a shank, a receiver, a lower compression insert with surfaces for closely receiving an elongate connecting member and a dual closure structure that may include a single flange or helical flange. The dual closure structure independently engages the connecting member and the lower compression insert. A threaded capture connection of the bone anchor includes a shank upper surface exclusively engaging the lower compression insert and a retainer threadably attached to the shank and spaced from the upper surface, the retainer configured for polyaxial motion with respect to the receiver prior to locking.

Abstract: The invention relates to a closing member for a sternal closure which is adapted to be mounted on a human or animal body in the region of the sternum for closing a cleft therein, wherein the closing member includes a first rear engaging area and a second rear engaging area, wherein, on the one hand, the first rear engaging area is prepared for positive securing on a first mounting area of the sternal closure on the one side of the cleft and, on the other hand, the second rear engaging area is prepared for positive securing on a second mounting area of the sternal closure on the other side of the cleft; to a sternal closure system comprising two first and second securing portions spaced apart from each other and adapted to be mounted on the human or animal body on both sides of a cleft in the region of a sternum as well as such closing member; and to a sternal closure.

Abstract: A spinal construct comprises a connector defining a longitudinal axis and extending between a first end and a second end. The connector defines a cavity and includes a member that is selectively disposable in the cavity at one of a plurality of positions between the ends. A first longitudinal element is dynamically movable within the cavity and engageable with the member to limit movement in a first axial direction. The first longitudinal element is connectable with vertebral tissue. A second longitudinal element is disposable within the cavity and connectable with vertebral tissue. Systems and methods are disclosed.

Abstract: A coupling assembly for coupling a rod to a bone anchoring element is provided, wherein the coupling assembly includes a receiving part having a first end, a second end, a central axis extending through the first end and second end, an accommodation space for accommodating a head of an anchoring element, a bore extending from the accommodation space to the first end, and a recess for receiving a rod. The accommodation space has an opening at the second end sized to permit insertion of a head of the bone anchoring element. The coupling assembly further includes a retainer element configured to be positioned at least partially in the accommodation space and being radially expandable and/or compressible to allow retaining a head inserted through the opening. The retainer element is held in position adjacent the opening by an engagement structure provided at or in the accommodation space.

Abstract: A pedicle screw distraction device that includes first and second pedicle screws each including a screw body portion and a ball head. The device also includes first and second screw head portions each including an internal threaded bore where the first screw is inserted in the first screw head portion and the second screw is inserted in the second screw head portion. The device also includes a connector link coupled to the first and second screw head portions where the connector link includes an outer perimeter portion having a slot therein. A spring member is positioned within the connector link between and in contact with the first and second screw head portions. A locking member including a plate and a separating portion is positioned between the screw head portions and an inside wall of the connector link where the separating portion is positioned between the screw head portions.

Abstract: A tool set for implanting a rod in a human spine in conjunction with bone screws. The tool set includes a pair of end guide tools that receive opposite ends of the rod in channels and under manipulation by a surgeon facilitate transport of the rod toward the bone screws attached to the guide tools. Intermediate guide tools having guiding pass through slots are utilized to guide intermediate locations along the rod toward associated bone screws. An attachment structure operably connects the guide tools to the bone screws. The guide tools each include a lower guide and advancement structure to allow a closure top with mating structure to be rotated and driven downward against the rod and to cooperate with similar structure in the bone screw to seat and lock the rod therein. A method utilizing the tool set allows a surgeon to percutaneously implant the rod in the patient.

Abstract: In one embodiment, the present invention includes a spinal osteosynthesis system comprising a connector, a connector member, a ring, and a bone anchor. The connector has an upper part disposed opposite of a lower part along a central axis. The upper part has a locking element and the lower part has a curved interior surface. The connector member can extend through the upper part along an opening axis transverse to the central axis. The ring may define a solid of revolution about the central axis. At least a portion of the ring may be receivable in the lower part of the connector. The bone anchor may have a head curved for polyaxial orientation with respect to the central axis. The locking element may be advanced towards the lower part to place the head of the bone anchor in contact with the connecting member, the ring, and the connector.

Abstract: The invention is a spinal fusion system with fusion rod anchors which do not use staples or screws to achieve securement to a patient's spine. The system relies on a head segment pivotally attached to a base having a channel imparted therein, the channel having an entry and exit opening. The rod anchor is secured with a threadable segment which is threaded through the channel and around an associated vertebra. Multiple rod anchors can be attached to a patient's vertebrae in this manner and a fusion rod is inserted into the multiple anchors and locked down inside the rod anchors with a lock nut.

Abstract: The invention discloses an implantable facet arthroplasty device suitable for treating adjacent level disease. The device is designed for implantation between a first vertebra and a second vertebra. Components of the device include: a crossbar; a first component having a first attachment mechanism adapted to attach to a first location of a spinal fusion device attached to a first vertebra and a second attachment mechanism adapted to attach to the crossbar; and a second component having a second attachment mechanism adapted to attach to a second location of a spinal fusion device attached to the first vertebra and a second attachment mechanism adapted to attach to the crossbar. The first component articulates relative to the second component and the first vertebra articulates relative to the device itself.

Abstract: Correction of a scoliotic curve in a spine comprises the steps of implanting an expanding rod isolated completely under the skin and attached to selected portions of the scoliotic curve of the spine at opposing ends of the rod; and producing a controlled force by means of expansion of the rod over at an extended time period under external control until a desire spinal curve is obtained. An incremental force is generated to stretch the scoliotic curve of the spine between the selected portions where attachment of the rod is defined. The controlled force is provided steadily for at least one month or alternatively 1-3 months. Multiple rods may be employed each associated with a different scoliotic curve of the spine or a different portion of the scoliotic curve.

Abstract: A rod system includes two rods each with a head and a shaft, two elastic members each fitted around one shaft against one head, and a case defining a first inner portion, a second inner portion, and a third inner portion in communication with the first and the second inner portions. A first rod with a first elastic member is seated in the first inner portion so the first elastic member abuts the bottom of first inner portion and the first head protrudes into the third inner portion. A second rod and a second elastic member is seated in the second portion so the second elastic member abuts the bottom of the second inner portion and the second head protrudes into the third inner portion and abuts the first head.

Abstract: A coupling assembly for use in surgical constructs comprises a first body and a second body. One of the first body and the second body includes a male member and an other of the first body and the second body includes a female member. The male member is sized and shaped to be received within the female member and the female member has an internal bore sized and shaped to receive the male member therein. A raised portion is formed on or attached to the male member. An area of decreased diameter is associated with the internal bore of the female member. The first and second bodies are coupleable to one another by an interference fit when the raised portion of the male member is positioned within the area of decreased diameter associated with the internal bore of the female member.

Abstract: A spinal fixation device is provided having first and second elongate members that are angularly adjustable relative to one another. Each elongate member can include a connecting feature formed on a terminal end thereof, and each connecting feature can be coupled to one another to allow angular movement of the first and second elongate members. The device can also include a locking mechanism that is adapted to couple to the connecting feature on each of the first and second elongate members to lock the elongate members in a fixed position relative to one another.

Abstract: An articulating assembly includes a first elongated element for attachment to a first anatomical region, and a second elongated element for attachment to a second anatomical region. In at least one embodiment, a coupling connects the first and second elongated elements. The coupling includes a moveable joint configured to allow polyaxial movement of the first elongated element with respect to the second elongated element. The assembly further includes a locking mechanism. The locking mechanism is operable in an unlocked condition to permit polyaxial movement of the first elongated element with respect to the second elongated element, and a locked condition to immobilize the movable joint and fix the position of the first elongated element with respect to the second elongated element.

Abstract: A spinal rod assembly may be formed by attaching an extension portion onto a spinal rod that extends along a longitudinal axis. The extension portion may include a rod coupler that attaches to the spinal rod with a first coupling that includes a first degree of rotational freedom and a first degree of translational freedom in positioning the rod coupler relative to the spinal rod along the longitudinal axis. The extension portion may further include an extender rod including an elongated rod body that may be secured to the rod coupler using a second coupling that includes at least a second degree of rotational freedom in positioning the extender rod relative to the rod coupler about an axis substantially perpendicular to the longitudinal axis. The extension portion may be assembled in situ to a spinal rod that has been previously secured to vertebral bodies in a patient.

Abstract: A device (1) according to the invention for externally fixing broken bones (62, 62?) of a patient, particularly the extremities, comprises a support (11) composed of a plurality of joint elements (2, 2) that are stringed together, wherein said support can be disposed outside the body of the patient. The proximal ends (41) of at least two percutaneously disposed pins (4) are anchored in the bone tissue (61) of the patient, and the distal ends (42) are fixed to the support (11). The joint elements (2) are stringed on a central tensile force element (3), and in each case two adjoining joint socket (22). The individual ball joints, and thus the support (11), can be fixed in a reversible frictionally engaged manner by applying a tensile force of the central tensile force element (3). The joint elements (2, 2?) in turn are designed such that a pin (4) can be fastened to the support (11) in a clamping and/or frictionally engaged manner by applying the tensile force of the central tensile force element (3).

Abstract: An adjustable articulating spinal rod system including a first elongated element secured to a first bone, a second elongated element secured to the spine, and an articulating joint connecting the first and second elongated elements. The articulating joint including a first movable joint, a second movable joint, and at least one locking mechanism. The first movable joint is coupled to the first elongated element and the second movable joint which is also coupled the second elongate element. The first and second movable joints are configured to allow polyaxial movement and rotation of the first elongated element with respect to the second elongated element. The at least one locking mechanism immobilizes the first and second movable joints in the locked position to secure the first elongate element in a position relative to the second elongate element and allow movement and rotation in an unlocked position.

Abstract: A spinal construct comprises a first member defining a longitudinal axis and extending between a first end and a second end being offset relative to the longitudinal axis. A second member defines a longitudinal axis and extends between a first end and a second end being offset relative to the longitudinal axis of the second member. The second ends are connected to define an axis of rotation such that the members are relatively rotatable about the second ends and the axis of rotation is offset relative to the longitudinal axes. Systems and methods are disclosed.

Abstract: Spinal rods are provided that transition from one diameter to another without an extended transition region to which coupling devices may not be attached, allowing coupling devices for mounting the spinal rod to the spine to be secured almost anywhere along the rod's length without having a weakened transition point.

Abstract: An intervertebral stabilization device and method is disclosed. The device preferably includes a planar spring enclosed within a housing. The housing is joined to an articulation component at either end, and the articulation components have couplings connectable to anchoring components which are securable to adjacent vertebrae. The planar spring can flex and retract providing relative motion between the adjacent vertebrae. The articulation components are ball and socket joints which allow the entire assembly to flexibly follow the curvature of the spine. A fusion rod with articulation components and couplings at either end may be substituted for the spring device. The couplings enable interchangeability between a fusion rod assembly and spring assembly, so that dynamic stabilization can occur at one vertebral level and fusion at the adjacent vertebral level. An overhung spring assembly with a sideways displaced housing which allows for a shorter pedicle to pedicle displacement is also disclosed.

Abstract: The invention consists of disc replacement implant for the lumbar spine designed for insertion into the disc space via a posterior approach. The implant can be stabilized in the disc space by connection to the vertebra or can be connected to dynamic spinal stabilization device consisting of interconnected bullets nested in a spring nested in a woven sleeve. By controlling the limits of elongation and compression the device prevents movement beyond normal physiological limits. In the midrange of movement flexibility is allowed. A method for using the dynamic spinal stabilization device is also provided.

Abstract: Vertebral fixation apparatus (1) arranged to correct spinal deformities. The apparatus includes a spinal support assembly having at least first and second support segments (3), the first support segment (3) includes at least one articulated joint (15) that is arranged to enable first and second support segments (3) to move relative to one another and locking means (21;45) for selectively locking the articulated joint (15). The apparatus further includes connector means (9) for connecting the first and second support segments (3) together, and anchor means (5) for attaching the first support segment (3) to a first vertebra (7) and for attaching the second support segment (3) to a second vertebra (7).

Abstract: A needle-coupled parallel mechanism is provided. The needle-coupled parallel mechanism is structurally improved so as to have a broad working area and a high precision. The needle-coupled parallel mechanism comprises a fixedly positioned frame, a main shaft, three first links, three second links, and a needle. The main shaft is arranged so as to be movable relative to the frame. One end of each of the first links is connected to the frame between both ends of the main shaft and the other end thereof is connected to one end of the main shaft. One end of each of the second links is connected to the frame between both ends of the main shaft and the other end thereof is connected to the other end of the main shaft. The needle is linearly movably coupled to the main shaft to perform a predetermined operation on a target object. Each of the first links and the second links has at least three joints selected from a prismatic joint, a 1-axis revolute joint, a 2-axis revolute joint and a spherical joint.

Abstract: An adaptive spinal rod is provided for connecting levels of an adaptive stabilization system to support the spine while providing for the preservation of spinal motion. Embodiments of the adaptive stabilization rod include a ball having an anchor system, a deflection system, a vertical rod system and a connection system. The deflection system provides adaptive stabilization and load-sharing. The adaptive spinal rod connects different levels of the construct in a multilevel construct. The adaptive spinal rod cooperates with the deflection system to further reduce stress exerted upon the bone anchors and spinal anatomy.

Abstract: Systems, devices, and associated methods for correcting spinal column deformities that help minimize a number of attachment anchors utilized for correction, facilitate use of straight or contoured rods, and/or help promote a more natural, physiologic motion of the spinal column.

Abstract: The present invention is directed to a dynamic fixation system for engaging, via bone fixation elements, one or more parts of a patient's body. Preferably, the dynamic fixation system is used to engage one or more vertebrae for stabilizing the attached vertebrae with respect to one another while still permitting the vertebrae to move with respect to one another. The dynamic fixation system may include a first rod having first and second ends, a second rod having first and second ends, and a damping component and/or a damping mechanism for interconnecting the first and second rods. In one embodiment, the damping component is injection molded in-between the one of the ends of the first rod and one of the ends of the second rod so that the first and second rods are prevented from separating with respect to one another but are still permitted to move with respect to one another.

Abstract: A coupling assembly for use in surgical constructs comprises a first body and a second body. One of the first body and the second body includes a male member and an other of the first body and the second body includes a female member. The male member is sized and shaped to be received within the female member and the female member has an internal bore sized and shaped to receive the male member therein. A raised portion is formed on or attached to the male member. An area of decreased diameter is associated with the internal bore of the female member. The first and second bodies are coupleable to one another by an interference fit when the raised portion of the male member is positioned within the area of decreased diameter associated with the internal bore of the female member.

Abstract: The present application is directed to methods and devices that provide for asymmetrical movement of vertebral members. In one embodiment, first and second anchors connect the rod to the vertebral members. The rod may be fixedly connected to the first anchor, and movably connected to the second anchor. A limiting device may be positioned on one or both sides of the second anchor. The limiting device or devices control an extent of movement between the rod and the second anchor during vertebral motion. In one embodiment, the device controls an amount of flexion and extension of the vertebral members.

Abstract: A posterior spinal fusion system may include pedicle screws and one or more segments designed to be attached to the implanted pedicle screws via nuts to fuse spinal motion segments in a modular fashion. The pedicle screws may have semispherical receiving surfaces, and each segment may have mounting portions at both ends, with corresponding semispherical engagement surfaces. The nuts may also have semispherical surfaces. The semispherical surfaces permit polyaxial adjustment of the relative orientations of the segments and pedicle screws. Each mounting portion may have a passageway therethrough to receive the proximal end of the corresponding pedicle screw; each passageway may intersect the edge of the corresponding engagement surface to facilitate percutaneous placement. Such placement may be carried out through cannulae to provide a minimally invasive (MIS) implantation procedure.

Abstract: Correction of a scoliotic curve in a spine comprises the steps of implanting an expanding rod isolated completely under the skin and attached to selected portions of the scoliotic curve of the spine at opposing ends of the rod; and producing a controlled force by means of expansion of the rod over at an extended time period under external control until a desire spinal curve is obtained. An incremental force is generated to stretch the scoliotic curve of the spine between the selected portions where attachment of the rod is defined. The controlled force is provided steadily for at least one month or alternatively 1-3 months. Multiple rods may be employed each associated with a different scoliotic curve of the spine or a different portion of the scoliotic curve.