Abstract: The present invention relates generally to a surgical device for the correction of deformities of the spinal column and finds particular, although not exclusive, utility in devices which are surgically implantable. Presently known implantable surgical devices are unable to provide for the progressive correction of spinal deformities assisted by active movements of the human body without fusion of the involved part of the spinal column. The present surgical device comprises a spinal column straightening means for permitting the relative rotation of two substantially adjacent vertebrae about a common axis substantially only in opposite rotational directions.

Abstract: A manipulation device includes a body portion, a plurality of articulatable legs, and at least one lock member. The legs extend from the body portion. Each of the legs is configured to engage a surgical instrument at a distal end thereof. Each of the legs is transitionable between an unlocked condition, wherein the leg is free to articulate, and a locked condition, wherein the leg is fixed in position. The at least one lock member is operably disposed within the body portion and is coupled to at least one of the articulatable legs. The lock member is rotatable relative to the body portion between an unlocked position and a locked position for transitioning the at least one articulatable leg coupled thereto between the unlocked condition and the locked condition.

Abstract: Disclosed is a spinal rod that includes an elongated flexible component and a reinforcing component. The reinforcing component is resistant to damage from compressive forces. The reinforcing component may be disposed circumferentially around at least a portion of the flexible component so as to define at least one compression slot. The reinforcing element may include an upper bracket, an opposing lower bracket, and a connecting pin extending therebetween.

Abstract: A connector assembly comprising a connector, spinal rod receiver, a washer and a compression member is provided. The connector extends between a first end and a second end configured for coupling to a bone fastener. The first end of the connector contains an upper surface and a lower splined surface configured for mating with a lower splined surface of a washer disposed between the first end of the connector and the rod receiver. The rod receiver containing a receiver body coupled to a threaded shaft. The rod receiver is configured for receiving a spinal rod and is attachable to the first end of the connector for selectively adjusting the direction of at least a portion of a spinal rod. The compression member connects the receiver with the first end of the connector for securing the spinal rod into the receiver body. Methods of use are also disclosed.

Abstract: The present application is directed to devices and methods for correcting a spinal deformity. A spacer is positioned between processes that extend outward from a pair of vertebral members. A force applicator is operatively connected to apply a force to the vertebral members. The spacer then acts as a fulcrum with the force causing the vertebral members to pivot about the spacer and become aligned in a more desired orientation to eliminate or reduce the deformity.

Abstract: The present application discloses methods for treating a spinal deformity. In one embodiment, an elongated member is attached to vertebral members with fasteners. A separate fastener may attach the elongated member to each of the vertebral members. The elongated member may apply a force to limit growth on one side of the vertebral members, such as a convex side of a scoliotic spine. Each fastener may be constructed to limit a direction of growth of the vertebral member thereby applying a specific, corrective force to the vertebral member. The fasteners may allow relative motion between adjacent vertebral members without losing the attachment between the vertebral members and the fasteners. The net result may be controlled modulation of growth to reduce and/or eliminate the spinal deformity through redirection of growth potential.

Abstract: A pedicle screw and rod fixation assembly including a pair of opposing tabs having a proximal end and a distal end, the pair of opposing tabs being coupled to one another about the distal end thereof by a screw head member, a decoupling mechanism for decoupling the pair of opposing tabs from the screw head member, a rod receiving slot between the pair of opposing tabs, and a sliding member configured for coupling to the pair of opposing tabs. The sliding member and the pair of opposing tabs are configured for allowing movement of the sliding member distally along the pair of opposing tabs and preventing movement of the sliding member proximally along the pair of opposing tabs.

Abstract: The present teachings provide one or more surgical implements for repairing damaged tissue, such as in the case of a spinal fixation procedure. A bone anchor is provided. The anchor can include a bone fastener. The bone fastener can include a head and a second end adapted to engage an anatomy. The bone fastener can extend along a longitudinal axis. The anchor can also include a coupling arrangement coupled to the head of the bone fastener so that the bone fastener is rotatable about the longitudinal axis to define a first plane of motion. The anchor can further include a saddle, which can be coupled to the coupling arrangement. The saddle can be movable relative to at least one of the bone fastener and the coupling arrangement to define a second plane of motion.

Abstract: A receiver body for an elongated spinal fixation element includes a housing portion with one or more flanges extending outwardly. In one embodiment, the receiver body includes first and second flanges extending outwardly from the housing portion. The housing portion includes first and second slots that form a passage through the housing portion. Each flange has a circular perimeter edge and a chamfered section, the chamfered section having a notched undercut for engagement with an instrument. In another embodiment, the receiver body includes a housing portion having a circular flange with a first chamfered section and a second chamfered section diametrically opposite the first chamfered section. The first chamfered section has a first aperture that opens out beneath the flange, and the second chamfered section has a second aperture that opens out beneath the flange. The first and second apertures form diametrically opposed pivot-attachment points for an instrument.

Abstract: A fixation system configured to releasably secure an orthopedic implant to a bone. The orthopedic implant has at least one lumen extending from a proximal portion to a distal portion configured to extend through cortical portions and into cancellous portions of the bone. The fixation system includes a flowable biomaterial that flows through the lumen into the cancellous portion of the bone in an expanded configuration with at least one dimension greater than a corresponding dimension on the orthopedic implant located generally along a pull-out direction of the orthopedic implant. An insert is positioned in the lumen and in engagement with the flowable biomaterial located in the cancellous portion of the bone, such that the orthopedic implant is detachable from the biomaterial in the cancellous portion of the bone to facilitate subsequent removal of the orthopedic implant from the bone.

Abstract: Anatomic points within the body are projected outside the body through the use of extenders (180, 182, 188). The projected points may then be used for measurement, or to facilitate the selection or configuration of an implant that is positioned proximate the anatomic points using a slotted cannula (143). Such an implant may be a rod (270) for a posterior spinal fusion system. Pedicle screws (140, 142, 148) may be implanted into pedicles of the spine, and may then serve as anchors for the extenders. The extenders (180, 182, 188) may have rod interfaces (214, 216, 218) that receive the rod (270) in a manner that mimics the geometry of the pedicle screws (140, 142, 148) so that the selected or configured contoured rod (270) will properly fit into engagement with the pedicle screws (140, 142, 148).

Abstract: A bone fastener includes a fixation portion configured to interface with boney tissue, a connection portion having a longitudinal axis and being configured to interface with an elongated support structure, and a flexible portion disposed between the fixation portion and the connection portion. The flexible portion is configured to permit flexure of the connection portion relative to the fixation portion. The flexible portion has a first set of opposed facing surfaces that mechanically limit the range of flexure in a first direction. It has a second set of opposed facing surfaces that mechanically limit the range of flexure in a second direction. The opposed facing surfaces are substantially transverse to the longitudinal axis.

Abstract: Provided is an iliosacral polyaxial screw system. A multiple part insert member is provided to secure the screw to the housing of the assembly to accommodate screws in which the shank diameter of the screw is greater than the bottom opening of the screw housing or greater than the opening of a ring member designed to capture the head of the screw in the housing.

Abstract: A distal loading receiver for a polyaxial bone screw includes a body member having a circumferential wall defining a bore disposed longitudinally through the body member. A skirt depends from a distal end of the body member. The skirt defines one or more distally opening slots and an abluminal surface of the skirt includes one or more transverse ribs proximate to a distal end of the skirt. A retaining ring includes a luminal surface having one or more transverse recesses proximate to a distal end of the luminal surface and one or more walls extending inwardly from the luminal surface. The slots accommodate the walls and the recesses accommodate the ribs to attach the body member to the retaining ring when the distal end of the skirt is inserted into a proximal end of the retaining ring.

Abstract: A surgical instrument includes a first member defining a longitudinal axis. A second member is disposed with the first member and is axially translatable relative to the first member. A first body is connected to the first member and is translatable along an arcuate path relative to the first member. The first body is connected to a first implant support. A second body is connected to the second member and is translatable along an arcuate path relative to the second member. The second body is connected to a second implant support. Systems and methods of use are disclosed.

Abstract: Compression-distraction spinal fixation systems, and methods of performing compression-distraction spinal fixation, are provided that include screw-rod constructs having a ratcheting mechanism. Bone screws of the screw-rod constructs can have a pawl that engages ratchet teeth on the rod of the screw-rod construct. The bone screw can be unidirectionally ratcheted along the length of the rod to apply compressive or distractive forces. Tools for manipulation of the screw-rod constructs are also provided, which tools include distal tips configured to engage the bone screws.

Abstract: An implant support comprises a first portion defining a longitudinal axis and a second portion including at least one arm extending from the first portion. The at least one arm includes a part. An extension is engageable with the at least one arm to move the at least one arm between a first position and a second position such that the part is disposed to releasably engage an implant. A lock is disposed with the first portion and connected with the extension. The lock is biased from a first configuration to a second configuration to engage the first portion and resist disengagement of the at least one arm from the second position. Systems and methods of use are disclosed.

Abstract: A spinal stabilization system may be formed in a patient. In some embodiments, a minimally invasive procedure may be used to form a spinal stabilization system in a patient Bone fastener assemblies may be coupled to vertebrae Each bone fastener assembly may include a bone fastener and a collar. The collar may be rotated and/or angulated relative to the bone fastener. Detachable members may be coupled to the collar to allow for formation of the spinal stabilization system through a small skin incision. The detachable members may allow for alignment of the collars to facilitate insertion of an elongated member in the collars. An elongated member may be positioned in the collars and a closure member may be used to secure the elongated member to the collars.

Abstract: A surgical instrument comprises a first member including a first body connected to at least one second body. The first body is configured for disposal of an implant support having an outer surface. The at least one second body includes a capture element configured to dispose an implant support having an outer surface with the at least one second body such that the outer surfaces are spaced apart and each of the implant supports are engageable with a first implant. A second member is connected with the first member and is engageable with a second implant. The members are relatively movable to dispose the second implant with the implant supports and to align the second implant with at least one of the first implants. Systems and methods are disclosed.

Abstract: A fixation system configured to releasably secure an orthopedic implant to a bone. The fixation system including at least one expandable member that is inserted through the lumen and positioned in cancellous bone near the distal portion of the orthopedic implant. A delivery tube delivers a flowable biomaterial to the expandable member. The expand fixation structure includes at least one dimension greater than a corresponding dimension on the orthopedic implant to secure the orthopedic implant in the bone. An insert is secured in the lumen to releasably attach the fixation system to the orthopedic implant. The expandable member is detachable from the orthopedic implant to facilitate subsequent removal of the orthopedic implant from the bone.

Abstract: A medical instrument for holding and handling a surgical securing element has a proximal and a distal end. The surgical securing element includes a securing part and a holding part, and is assembled such that in an assembled disposition, the holding part for a connection element is movable in relation to the securing part. The instrument defines a longitudinal axis and includes a pulling part and, movable in relation to the latter in the direction of the longitudinal axis, a pushing part. The proximal end is temporarily couplable to the securing element in the assembled disposition. The instrument further includes an uncoupling device for actively transferring the instrument from a coupled position, in which the pulling part and the holding part are coupled, to an uncoupled position, in which the pulling part and the holding part are separable from one another.

Abstract: A dynamic fixation medical implant having at least two bone anchors includes a longitudinal connecting member assembly having rigid sleeves for attachment to the bone anchors, at least one spacer engaging the bone anchors and the sleeves, and in some embodiments, an end elastic bumper. A flexible cord is initially slidingly received within the rigid sleeves, the spacer and the bumper. The spacer may include an optional inelastic inner liner, with at least one of the sleeves having an extension slidingly receivable within the liner. Some sleeves include apertures for receiving a closure top portion for locking the cord against the sleeve, or alternatively receiving a closure top that does not extend into the aperture, the slip or grip option provided by the aperture in each sleeve resulting in an overall connector with variable segmental stiffness.

Abstract: A polyaxial bone screw assembly includes a shank body having an upper head portion with a mating segment and a first partial spherical surface, a retainer structure being mateable with the mating segment of the upper head portion, the retainer structure having a second partial spherical surface such that when mated, the first and second partial spherical surfaces form a spherical ball member, a receiver defining an open channel and having a base with a seating surface partially defining a cavity, the open channel communicating with the cavity, the cavity communicating with an exterior of the base through an opening sized and shaped to receive the shank upper head portion therethrough, and a bushing sized and shaped to fit within open channel and cavity, the bushing having a lower rounded surface engageable with a top surface of the spherical ball member formed by the shank and retainer structure.

Abstract: Open implant closure structures include a helically wound guide and advancement flange form having splay control surfaces. Multi-start closures and closures with inner set screws have splay control contours for interlocking with cooperating flange forms of bone anchor receivers. Flange form heights, thicknesses and other geometry, such as splay control ramp angle may be varied.

Abstract: There is provided a modular polyaxial pedicle screw assembly that includes various components which may be configured in various manners so as to provide different functionalities to the pedicle screw assembly. This advantageously decreases surgery time, reduces repetitive and tedious surgical steps, and allows for streamlining inventory of expensive medical equipment. In one embodiment, a pedicle screw assembly includes a pedicle screw, a rod holding element, a polyaxial insert, a rod, and a set screw. The pedicle screw includes a threaded shaft and a cap. The rod holding element includes a screw hole, an insert bearing area, a chamber, chamber walls, a saddle area, and a threading area. The insert is disposed within the chamber, and the insert defines a bearing surface, an upper surface, side walls and a receiving area.

Abstract: A polyaxial bone screw assembly includes a shank body having an upper head portion with a mating segment and a first partial spherical surface, a retainer structure being mateable with the mating segment of the upper head portion, the retainer structure having a second partial spherical surface such that when mated, the first and second partial spherical surfaces form a spherical ball member, a receiver defining an open channel and having a base with a seating surface partially defining a cavity with a shaped wall, the open channel communicating with the cavity, the cavity communicating with an exterior of the base through an opening sized and shaped to receive the shank upper head portion therethrough, and a bushing sized and shaped to fit within open channel and cavity and lock in recesses on interior of receiver.

Abstract: Various methods, devices, and systems are disclosed that facilitate easier and more compact implantation of osteosynthesis devices. In some embodiments, implants are screwed into two vertebrae and a plate is used to hold and displace the spine. In some plate embodiments, at least one longitudinally elongated opening is disposed at one end of the plate and partially opening onto an edge of the plate. In some plate embodiments, at least one longitudinally elongated opening is disposed at one end of the plate having a portion sufficiently large to be inserted without disassembly in the fixation means of an implant already screwed into the spine when the fixation means are already assembled.

Abstract: Apparatus for use in stabilizing and/or aligning the spinal column utilizes hooks and rods to effectively transfer load from the vertebrae to the apparatus regardless of the angle and the height of the pedicular screws. A screw cap formed of a base having a bore therethrough for receiving the head of the screw, an upright riser formed thereon that is laterally offset from the bore, and a surface for engaging the rod or plate of the stabilizer enables the apparatus to be used for stabilizing and/or aligning vertebral bodies that are out of alignment, of different shape or size, and/or pathology. The apparatus is implanted in a series of steps that are quickly and conveniently performed in the surgical stage and with minimal application of force to align the vertebral bodies, decreasing the likelihood of damaging the nerves populating the surgical stage.

Abstract: A stabilizer device for the spinal column, comprising first engagement means and second engagement means, which are adapted to be connected to each other by a rod-like element, the first and second engagement means being adapted to be fitted on first and second pedicle screws, which are adapted to be in turn inserted in two adjacent vertebrae, the first and second engagement means being fixable on the pedicle screws; the first and second engagement means accommodate bearing means, which are adapted to rotate within the first and second engagement means and to be fitted on the pedicle screws, in order to allow the fitting of the first and second engagement means on the pedicle screws.

Abstract: A spinal fixation device may include a bone anchoring member, a rod receiver, and an connection member. The rod receiver may include a channel for receiving a rod projection from a first adjacent fixation assembly. The rod receiver may have a central axis such that the channel is generally perpendicular to the central axis. The connection member may have a rod projection configured to extend to a second adjacent fixation assembly. The rod receiver may be coupled to the connection member and rotatable about the central axis of the rod receiver. The interior fixation assembly may be axially fixed such that the bone anchoring member, the rod receiver and the connection member are not translatably movable relative to each other.

Abstract: A polyaxial pedicle screw includes a threaded shaft portion for anchoring the pedicle screw in a vertebra, the pedicle screw having one axial end provided with a shaft head which is coupled to a mounting sleeve for a longitudinal beam in a rotatable and/or pivotable manner, including a fixing device for the selective positional fixation of the mounting sleeve with respect to the shaft portion. The fixing device includes a locking element as well as a counterforce part which is formed so as to be separate from the pedicle screw and counteracts the holding force of the locking element, preferably a grub screw or threaded nut, and is designed and/or retained in such a manner that the holding force of the locking element can be selectively released by means of the counterforce part, viz. is without any effect.

Abstract: A device and method for inserting a vertebral stabilization member is disclosed. The stabilization member is releasably clampable to an insertion device between first and second clamping members at a clamping location spaced from a midline of the stabilization member. The insertion device and stabilization member are deliverable through an access sleeve and the stabilization member is rotatably actuatable to position the stabilization member in relation to a bone anchor.

Abstract: Methods of correcting a spinal deformity, including securing a first rod on a first side of a spine, securing an anchor on a second side of a spine, securing a lateral coupling between the rod and the anchor, translating and/or derotating the spine and securing a second rod on a second side of the spine to provide secondary stabilization to the spine.

Abstract: Anatomic points within the body are projected outside the body through the use of extenders (180, 182, 188). The projected points may then be used for measurement, or to facilitate the selection or configuration of an implant that is positioned proximate the anatomic points using a slotted cannula (143). Such an implant may be a rod (270) for a posterior spinal fusion system. Pedicle screws (140, 142, 148) may be implanted into pedicles of the spine, and may then serve as anchors for the extenders. The extenders (180, 182, 188) may have rod interfaces (214, 216, 218) that receive the rod (270) in a manner that mimics the geometry of the pedicle screws (140, 142, 148) so that the selected or configured contoured rod (270) will properly fit into engagement with the pedicle screws (140, 142, 148).

Abstract: A bone anchor assembly for coupling an offset bone anchor with a previously inserted spinal fixation element and method of use is provided. Exemplary embodiments of a bone anchor assembly are particularly suited for use in a rod-first spinal surgical technique in which a bone anchor inserted into a patient vertebra may be separated from a previously inserted spinal fixation element by a separation distance.

Abstract: The present invention provides an implant that can be inserted on top of a previously placed spinal fixation element. The implant includes a bone anchor and a connector body. The bone anchor includes a proximal head and a distal shaft extending along a longitudinal axis configured to engage bone. The connector body is configured to engage the proximal head of bone anchor and engage a spinal fixation element offset from longitudinal axis of the bone anchor shaft. Because, the implant is inserted over the spinal fixation element, direct visualization of the surgical site is available during insertion. In addition, the implant may provide tactile or audible feedback indicating that the spinal fixation element has been engaged by the implant.

Abstract: A polyaxial pedicle screw includes a housing, a bone screw member, and an anvil. The bone screw member includes a head and a threaded shaft extending from the head. The head is selectively securable within the housing. The anvil is positionable within the housing adjacent to the head of the bone screw member when the anvil and the head of the bone screw member are positioned within the housing. The anvil may define one or more grooves in an outer surface of the anvil. The groove defines a flap that is flexibly attached to the anvil to enable the anvil to flex an amount sufficient to maintain the head of the bone screw in constant contact with the anvil when the bone screw member is moved relative to the anvil.

Abstract: The present invention provides a minimally invasive surgery pedicle screw system, including: a plurality of slotted guides that are selectively inserted through one or more surgical incisions; a plurality of pedicle screws selectively coupled to the plurality of slotted guides that are selectively secured to one or more bony anatomical structures; a pendulum mechanism selectively translatably and pivotably coupled to one of the plurality of slotted guides; and a connecting rod selectively translatably and pivotably coupled to one of the plurality of slotted guides; wherein the pendulum mechanism is selectively coupled to the connecting rod. The connecting rod is selectively secured to one or more of the plurality of pedicle screws.

Abstract: A spinal implant for connecting to an elongated rod is disclosed. The spinal implant includes a yoke having a first end and a second end, the first end having a first and second rod engaging portion and a channel between the first and second rod engaging portions for encompassing a first bone anchor, and the second end being spaced apart from the first end. An extension rod is also provided which extends from the second end of the yoke parallel to the elongated rod. The first and second rod engaging portions are configured and dimensioned to receive first and second securing member for securing the elongated rod.

Abstract: A Spinal column implant for elastic stabilization of vertebrae includes an elastic rod that is anchored in a non-positive fit fashion in the receptacle of a pedicle screws by means of a mobile filling piece and a clamping element. The non-positive fit is supported additionally by a dynamic form-fit contribution upon exposure to load.

Abstract: Compression-distraction spinal fixation systems, and methods of performing compression-distraction spinal fixation, are provided that include screw-rod constructs having a ratcheting mechanism. Bone screws of the screw-rod constructs can have a pawl that engages ratchet teeth on the rod of the screw-rod construct. The bone screw can be ratcheted along the length of the rod to apply distractive or compressive forces.

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: A spinal implant system for use in immobilizing adjacent vertebral bodies in a minimally invasive manner, including a pair of implants having lengths sufficient so that one of the ends extend outside of a patient's body when the implants are installed. Each implant has a pair of opposed elongated posts which in conjunction with an orthogonally arranged support surface define a transverse opening for receiving a stabilizing rod. A cap having upper and lower surfaces is associated with each implant, each cap and its associated post has means for advancing the cap along the posts toward the support surface to lock a stabilizing rod therebetween. The rod is pivotally coupled to one of the caps so that the rod, when pivoted, will extend between the transverse openings in adjacently installed implants.

Abstract: A bone screw assembly includes a screw body, including anchor portion and rod-receiving portion, and a rod seat movably mounted in the screw body to allow for controlled angulation between a spinal connection element disposed in the rod seat and the screw body. The rod seat is pivotable in one or more selected directions about one or more axes relative to the screw body. The rod seat may include a first lower rod seat element disposed in a recess of the screw body having a cylindrical bottom surface to facilitate pivoting in a first direction. A second lower rod seat element is stacked on the first lower rod seat element and has a conical bottom surface abutting a top surface of the first lower rod seat element to facilitate pivoting in a second direction.

Abstract: This invention relates to a orthopedic implant that comprises a shape memory polymeric material. The orthopedic implant can be fabricated or molded in a desired configuration selected to provide support or tension to bony structures. Examples of implantable devices include spinal rods, bone plates, and bone fixation cords. The orthopedic implant can be deformed to a second configuration different from the first configuration either prior to implantation or after implantation. When desired, the shape memory polymeric material can be induced to revert to it original molded configuration. This can compress the attached bony structure and/or promote arthrodesis.

Abstract: An osseous anchoring implant, various embodiments of which comprise an osseous anchor and a head bearing fixation structure capable of receiving and fixing at least one bar, the head of the implant being traversed by at least one duct, which receives the bar through a lateral aperture, and by a threaded channel, whose axis is not parallel to the axis of the duct, which receives a fixation screw of the bar, the implant being characterized in that it comprises fixation structure of the head on the part of the implant which extends from the osseous anchor, these fixation structures allowing, prior to blocking and fixing, at least a determined mobility of the head around at least one axis not parallel to the axis of symmetry of the osseous anchor. The fixation screw of the bar may comprise a ball and socket at its base.

Abstract: An apparatus, system, and kit of components useful as a stabilization or correction system for a spinal column, especially in the field of pediatrics. A smooth unthreaded rod or a threaded rod is used that can be straight, rigid, bent or flexible depending on the body condition to be addressed. The rod may be bent or flexible to achieve varying degrees of lordosis (backward curvature) or kyphosis (forward curvature) before being affixed to the anchoring means and apparatus. The straightness, curvature, bent, or flexibility of rod depends upon the location along the spinal column. Once installed to the vertebrae, the rod provides the proper, desired curvature and stabilization for the spinal column. Sharp edges and corners of the apparatus are eliminated by rounding the edges and corners.

Abstract: A sleeve system for lining a hole of a surgical screw in a bone or tissue of a subject includes a woven sleeve having a first end, a second end, and an elongated body. The elongated body has an interior portion. The first end includes an aperture that accesses the interior portion. The sleeve system also includes a protective tip that may be inserted through the aperture of the first end of the sleeve. The protective tip at least partially protects tissue of the subject from a screw positioned within the sleeve.

Abstract: A method for mounting a polyaxial screw into a bone includes rotating a drive cap so that a screw mounted to the drive cap is screwed into a bone, the drive cap having a socket in which a portion of the screw is pivotably disposed, at least a portion of a collet being disposed within the socket between the screw and the drive cap. A stabilizing structure and a fastener are positioned onto a shaft projecting from the drive cap. The fastener is advanced along the shaft so as to push a portion of a compression cap against the collet which in turn wedges the collet within the socket of the drive cap and causes the collet to bias against a portion of the screw, thereby locking the position of the screw, the collet, and the drive cap relative to each other.

Abstract: A bone fixation assembly comprises a tulip-shaped assembly and a bone fixation device such as a surgical or pedicle screw, comprising a head and a bone fixation portion. The tulip assembly comprises an upper portion to receive a rod and a lower portion that has a cavity in which the head of the bone fixation device rests. The cavity has an aperture below. The aperture has a length through which the tulip assembly may slide with respect to the bone fixation device, for movement of the tulip assembly when the bone fixation device is in place, while also maintaining the angular movement of the tulip assembly. The bone fixation device may comprise an aperture engaging part, which locks the bone fixation device position on the aperture length. A tulip assembly translation mechanism comprises a head, a cavity, an aperture to the cavity.