Abstract: A bone repair eyelet (1) comprises a single piece that has a hollow shaft (10), a supporting edge (15) and two rods (11) extending from the inner wall of the hollow shaft (10) to a ring (13) having an opening (12) located in the center of the shaft (10). The opening (12) extends in the longitudinal direction (A) of the shaft (10). Thus, the hollow shaft is divided into three passages which are separated from one another.

Abstract: A variable height, multi-axial bone screw assembly including a bone screw, a collet, a tulip shaped connector, a crown member, a rod and a set-screw. The bone screw has threads at its lower end and a generally cylindrical shaft at its upper end. The collet has a cylindrically shaped lower end to hold and grasp the bone screw shaft as well as a generally bulb shaped upper end to be received by the tulip shaped connector. By changing the position of the bone screw shaft grasped by the collet, the height of the bone screw vis-à-vis the tulip shaped connector can be varied. All the elements of the bone screw assembly are combined together by placing the collet head, crown member and rod within a central bore of the connector and firmly tightening them in place using the set screw.

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 anchor assembly for use with a fixation system for stabilizing one or more spinal bone segments by means of an elongated stabilizer includes an anchor base that receives a fastener and includes s a first coupling feature including guide slots and a recessed channel for receiving the elongated stabilizer. The anchor assembly further includes a cap that has a second coupling feature that is complementary to the first coupling feature and includes structures that are laterally received in the base guide slots for mating the cap to the base, as well as a stop element that in combination with the first coupling feature limits the lateral movement of the cap in the guide slots. The cap includes a retaining element that is driven into engagement with the elongated stabilizer so as to lock and retain the elongated stabilizer in place within the anchor assembly.

Abstract: Pedicle screws that can include a pedicle screw body, housing, plurality of clamps, rod, and set screw are disclosed herein. The clamps may be positioned side by side inside the lower portion of the housing. When the rod and set screw are provided in the housing, the set screw applies a force on the rod and the rod engages the plurality of clamps, causing the clamps to frictionally engage a head of the pedicle screw between the clamps.

Abstract: A pedicle screw for use in the treatment of a spinal deformity includes a head assembly and a fastener portion extending from the head assembly. The pedicle screw includes a head assembly and a fastener portion that extends from the head assembly. The fastener portion extends from the head assembly and is adapted to be secured to a vertebra of a spinal column. The head assembly includes a stationary member and a movable member. The movable member is supported on the stationary member for movement (such as pivoting movement) relative thereto between an opened position and a closed position. When the movable member is in the opened position, the head assembly is adapted to receive a longitudinal member therein for treatment of a spinal deformity. Thereafter, the movable member can be moved to the closed position to properly align the pedicle screw with the longitudinal member. A locking member and a retention member can then be used to maintain the movable member in the closed position.

Abstract: To provide a screw fastening device that, when performing a screw tightening operation, can substantially reduce the running torque directly applied by external force to a screw driving device.

Abstract: A polyaxial fastener assembly including a mechanical fastener having a proximal end and a distal end, the proximal end including a contact stress element, an articulating element disposed on the mechanical fastener adjacent and distal to the contact stress element, the articulating element having a convex surface and the contact stress element having a convex surface, and a receiver member adapted to receive therein the mechanical fastener, the receiving member having a first aperture having a concave bearing surface that articulates with the convex surface of the articulating element, a second aperture adapted for receiving therein an auxiliary mechanical fastener, and a third aperture for receiving therein a connector element, the third aperture being arranged with respect to the first and second apertures such that a connector element disposed in the third aperture is disposed between the contact stress element and the auxiliary mechanical fastener.

Abstract: A receiving part for receiving a rod for coupling the rod to a bone anchoring element, the receiving part including: a receiving part body having a channel for receiving a rod and defining an accommodation space for accommodating a head of a bone anchoring element, the accommodation space having an opening for inserting the head; and a pressure element at least partially in the accommodation space, the pressure element including a first portion having a recess to receive the rod, and a second portion having a flexible portion to clamp the head, wherein the pressure element is moveable along a longitudinal axis of the receiving part body from an inserting position to insert the head, to a pre-locking position to clamp the head in the receiving part by a pre-stress exerted by the pressure element, to a locking position to lock the head in the receiving part.

Abstract: A bone anchoring element (1) for anchoring an external device in a bone is described. A head (2) capable of connection to the external device is provided with a shaft (3) that can be anchored in a bone. A predetermined section of the shaft (3) has a bone thread (5). Moreover, the shaft (3) also has at least one bone thread-free surface (6,7; 11,12; 16,17; 21,22,23) that extends from a first end to a second end of the predetermined section essentially along the direction of the shaft axis. The bone anchoring element (1), thus provided, is pressed or soft-hammered into a hole (8, 28) previously generated in the bone and fixed in the bone by rotation by a predetermined angle. If the bone anchoring element has to be removed this can be achieved by unscrewing it in the standard fashion. The disclosure also describes methods for using the bone anchoring element.

Abstract: A method for attaching soft tissue to bone. The method includes forming a bore in a bone, placing the soft tissue adjacent to the bone and above the bore, at least partially inserting a fixation device into the bore, and delivering biologic material through the soft tissue at an interface area between the soft tissue and the bone.

Abstract: A sacral reconstruction fixation device aids in stabilizing the pelvis and the lumbar spine after a sacrectomy in cooperation with a spinal rod and transiliac rod. A pair of the fixation devices may be secured to respective ilia and respective spinal rods. The transiliac rod may be secured to both of the fixation devices. The fixation devices include first and second parts that are initially relatively rotatable about a common axis to aid in connecting the fixation devices to the spinal rod and transiliac rod. The body part is intended to be mated to the spinal rod, while the second part is intended to be mated to the transiliac rod. The fixation device's parts are subsequently locked against rotation and against longitudinal translation, advantageously both relative to each other and the rods.

Abstract: A bone anchoring nail is provided having a threadless shaft with a free end, a head opposite to the free end, the head having a substantially U-shaped recess for accommodation of a rod or a rod-shaped element, a longitudinal bore extending through the shaft and opening towards any one of the head and the free end and a plurality of openings extending through the wall of the shaft and being in communication with the bore. The bone anchoring nail allows quick insertion and reliable fixation enhanced by the in-growth of blood vessels.

Abstract: An apparatus includes a bone screw and a retention member. The bone screw has a proximal end portion and a distal end portion. The distal end portion of the bone screw includes a threaded portion. The retention member is coupled to the proximal end portion of the bone screw such that movement of the retention member relative to the bone screw is limited. The retention member is configured to deform when moved from a first configuration to a second configuration.

Abstract: An implantable screw for maintaining space during bone grafting procedures is provided, where the screw has a highly-polished contoured head having a region adapted to support soft tissue, a threaded shaft and a tip adapted to penetrate bone tissue. Also provided, a device combining multiple implantable screws in series in order to increase the available space to grow new bone and a method for implanting the implantable screw. The implantable screws provided may be used in conjunction with bone graft materials and are removable once a desired amount of new bone is generated.

Abstract: A coupling assembly that is configured to couple a surgical screw to another coupling assembly and another surgical screw is disclosed. The coupling assembly comprises a body that includes a receptacle configured to receive a head portion of the surgical screw and hold the head portion through an interference fit. The body further includes either a female member, a male member, or both, the female member and the male member configured to mate with a female member and a male member of the another coupling assembly and thereby join the coupling assembly to the another coupling assembly. Embodiments of the coupling assembly provide for adjustment of the distance between the coupling assemblies, as well as misalignment of various axes of the coupling assembly relative to the surgical screw and the male member. Exemplary embodiments provide fewer parts, greater flexibility during the surgical implantation, and a smaller profile than previous coupling mechanisms.

Abstract: A threaded bone anchor includes a plurality of recesses formed lengthwise along an exterior cylindrical surface for engagement with a driver instrument through which a user applies clockwise or counterclockwise torque for the insertion or removal of the bone anchor into and from bone. The bone anchor includes a cross-sectional geometry that minimizes the anchor's outer diameter, survives high insertion/removal torque without compromising the anchor's bending/shear strength, and allows a mating clamp to be attached to the entire non-threaded surface, including the recessed portion.

Abstract: Among other things, there is disclosed an orthopedic plate system for use in supporting or stabilizing long bones in pediatric patients. The plate includes a substantially planar portion for placement along a diaphysis of a long bone and a portion curved out of the plane of the planar portion for placement along at least part of a metaphysis of the long bone. Holes through the plate are provided for screws in both the curved and planar portions, which hold the plate to the long bone. The holes are substantially parallel to each other and substantially perpendicular to the plane of the planar portion. Screws through the holes and into the bone are substantially parallel to an epiphyseal plate of the long bone, so that attachment of the plate to the bone does not adversely affect growth of the long bone.

Abstract: Expandable support devices for tissue repair are disclosed. The devices can be used to repair hard or soft tissue, such as bone or vertebral discs. A method of repairing tissue is also disclosed. Surgical devices and methods for adjusting (e.g., removing, repositioning, resizing) deployed orthopedic expandable support devices are also disclosed. The expandable support devices can be engaged and surgically implanted by an engagement device and affixed to bone to provide stability and support for the devices. The expandable support devices are attachable to spinal fixation devices such as screws or plates, and may be used to support such devices when placed in weakened or damaged areas of bone.

Abstract: A surgical implant engageable by a surgical tool having spaced apart jaws with inward facing tubular protrusions, is provided. The implant includes a body for interfacing with a bone structure. The implant also includes a head connected with the body having spaced apart posts juxtaposed by a stabilization member receiving area. Each post has an outward side face that includes an upper generally vertical surface intersecting with a generally inward directed under surface that in turn intersects with a lower generally vertical surface. The side face has a generally tubular cylindrical indention intersecting the upper vertical surface and the inward directed under surface.

Abstract: A medical implant assembly includes a polyaxial bone anchor having a shank, a receiver and a retainer structure for capturing and supporting an upper end portion of the shank in the receiver. The shank includes radially extending projections on its upper end and the retainer structure includes shelves with seating surfaces for receiving and supporting the shank projections. Some embodiments include a lower compression insert.

Abstract: A compression screw assembly includes a first primary member having a threaded leading portion of a first pitch, a smooth middle portion and a threaded trailing portion of a second pitch with the trailing portion residing directly opposite leading portion. The compression screw assembly includes a second threaded screw head member positioned at a distal end having external threads, which are of the same pitch as the plurality of threads of the leading portion, and internal threads of a fourth pitch and dissimilar screw leads from the external threads. The difference in screw leads causes the compression screw member to apply a compressive force on bone fragments when compression screw assembly is inserted into bone fragments.

Abstract: The invention relates to a device for stabilizing the spine, comprising a bone screw (1) having a screw shaft (2) and having a first threaded portion (5) for insertion into the bone, comprising a rod (3) and a connector (4) that may be fixed to the bone screw (1) for the releasable connection of the rod (3) to the bone screw (1). The connector (3) comprises a connector body (9) having a throughgoing hole (10) and a rod seat (11) that is open on one side, into which the rod (3) may be snap fitted.

Abstract: In an exemplary embodiment, the present invention provides an anchor assembly that can be used for the fixation or fastening of orthopedic devices or instruments to bone tissue. In particular, the present invention preferably provides a variable angle or fixed angle anchor assembly that is able to securely connect the orthopedic device to bone tissue even when there is a variance in the angle and position of the assembly with respect to the device. Furthermore, in an exemplary embodiment, the present invention provides an anchor assembly having a locking mechanism that will quickly and easily lock the anchor assembly with respect to the orthopedic device.

Abstract: A coupling assembly is provided with a yoke device that allows an anchor member secured thereto to rotate in a turret-like manner with respect to an elongate member secured by the yoke in addition to allowing the anchor member to pivot away from the central axis of the yoke. A first yoke member holds the elongate member and is rotatably coupled to a second yoke member that holds a bone anchor. A combination of rotation of the second yoke member and pivoting of the anchor member allows the anchor to be positioned in a wide variety of orientations with respect to the yoke device and elongate member.

Abstract: A spinal fixation assembly and capless multi-axial screw system and method are shown. The assembly comprises a receiver having a rotary lock which in one embodiment includes a plurality of channels which urge and lock the elongated member to the screw using a bayonet type connection.

Abstract: Disclosed is a medical fastener that can be mounted to a bone of a patient. The medical fastener can include a head portion comprising a recess having a first portion, a second tapered portion extending from the first portion, and a third cylindrical portion extending from the second tapered portion. A threaded body portion can extend from the head portion. The first portion and the second portion can have a Torx geometry or star-shaped configuration. Also disclosed is a driver usable to mount the medical fastener to the bone. The driver can include a tip that is complementary to the recess and an end that enables the driver to mount to a drill or other device that can rotate the driver.

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: The present invention is directed a polyaxial bone fixation element for use in spinal fixation to interconnect a longitudinal spinal rod with a patient's vertebra. The polyaxial bone fixation element preferably includes a bone anchor, a collet, a body, and a locking cap. The polyaxial bone fixation element preferably enables in-situ assembly. That is, the polyaxial bone fixation element is preferably configured so that in use, the bone anchor may be secured to the patient's vertebra prior to being received within the body. Accordingly, the polyaxial bone fixation element enables a surgeon to implant the bone anchor without the body to maximize visibility and access around the anchoring site. Once the bone anchor has been secured to the patient's vertebra, the body can be snapped-onto the bone anchor. The bone anchor preferably also includes a second tool interface so that a surgical instrument can be directly coupled to the bone anchor.

Abstract: A bone fixation assembly. The bone fixation assembly includes a fixation member defining at least one aperture, wherein the aperture is adapted for engaging non-threadably and selectively a locking or a non-locking fastener.

Abstract: Exemplary spinal fixation devices, systems, and method are provided for stabilizing vertebrae in a patient's spine. In one exemplary embodiment, methods and devices are provided for coupling one or more bone anchors, such as hooks, screws, etc., and/or one or more spinal fixation elements, such as spinal rods, cables, plates, etc. In certain exemplary embodiments, a cross connector is provided for connecting and stabilizing two bone anchors, a bone anchor and a spinal fixation element, or a bone anchor and bone.

Abstract: A medical implant assembly includes a polyaxial bone anchor having a shank with an upper portion, a receiver, a retainer for holding the shank upper portion in the receiver, a lower compression insert with surfaces for closely receiving an elongate connecting member and a closure structure that may independently engage the lower compression insert to lock the shank with respect to the receiver while selectively not locking the elongate member. Projections or splines of the shank upper portion mate with holding pockets on the retainer. The bone anchor includes a shank upper surface exclusively engaging the lower compression insert that is spaced from the retainer, the retainer and shank being configured for polyaxial motion with respect to the receiver prior to locking.

Abstract: An apparatus includes a screw, an actuator and a spacer. The screw has a distal end portion and a proximal end portion. The distal end portion of the screw is configured to be threaded into a bone tissue. The proximal end portion of the screw has a surface. The actuator is threadedly coupled to the screw, and has an actuation surface defining a line substantially non-parallel to and substantially non-normal to a longitudinal axis of the screw. The spacer has a first surface substantially parallel to and in contact with the surface of the proximal end portion of the screw. The spacer has a second surface substantially parallel to and in contact with the actuation surface of the actuator. The actuator is configured to move the spacer relative to the screw between a first position and a second position.

Abstract: An absorbable screw fastener and a method of firing with an applicator capable of applying a surgical fastener to tissue in order to form tissue connection to secure objects to tissue, the fastener including a body portion having a helical thread, a head portion disposed at the proximal end of the body portion. The head portion includes a driver receiving configuration on its outer surface. The screw fastener further includes a cannulated center lumen with an opening extending from the head portion through the longitudinal length of the body portion.

Abstract: A pedicle screw assembly and method of assembly comprises a longitudinal member; a screw head comprising a bulbous end, wherein the screw head has a slot adapted to receive the longitudinal member; a bone fixator component comprising a concave socket having a biased angled top and a rounded bottom adapted to receive the screw head; a locking pin adapted to engage the screw head, the bone fixator component, and the longitudinal member; and a blocker adapted to engage the screw head and to secure the longitudinal member. Additionally, the bone fixator component may be configured as any of a bone screw and a hook.

Abstract: Bone screws have heads which are provided with a hex socket as well as a threaded portion. A screw driver system includes a hex driver and a threaded driver. The screw driver system permits driving the screw through a plate system into a bone until desired compression is obtained. Then the screw is locked to the plate while maintaining the imparted compression.

Abstract: A polyaxial screw assembly includes an internal load dampening mechanism for sharing and dampening loads between at least one screw member and at least one rod member interconnected by the assembly. A method of interconnecting the orthopedic screw with the rod includes dampening with a body member interconnecting the screw to the rod.

Abstract: The pedicle screw (1) for intervertebral support elements (3) consists of a shaft (10) and a head (2) comprising at least two parts (20, 22). The head is formed as a securing means for at least one support element (3). Each support element consists of a piece of a cable-like band (31) and a cylindrical support body (30) with an axial lumen (31? containing the band. The band is securable outside end surfaces (32) of the support body in the head. The head is formed with a contact surface (23) via which a pressure stress can be exerted on the support body in the band direction, and indeed using the band and in cooperation with a further pedicle screw.

Abstract: One aspect relates to augmenting positioning of an originally unsecured attachment element with respect to an originally unsecured bridging element. Another aspect relates to a surgical theater mechanism that can be at least partially fabricated at least partially based on position augmenting a first surgical theater element relative to a second surgical theater element. Yet another aspect relates to controlling positioning of a bony element at least partially by augmenting positioning of an originally unsecured attachment element relative to an originally unsecured bridging element. Still another aspect can relate to a shunt tube configured to be augmented secured with respect to a shunt device, at least partially to configure the shunt device into an operable position.

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 dynamic screw assembly includes a screw head having a pair of diametrically opposed arms, a slot between the arms, an inwardly curved bottom portion, an outwardly protruding and expandable bulbous end extending from the inwardly curved bottom portion and an opening positioned through the bulbous end, a bumper mechanism adjacent to the screw head that adjusts an angle of the screw head to a desired location in the dynamic screw assembly, a fixation component coupled to the bumper mechanism, a saddle connection positioned in the opening and engaging the screw head and the fixation component, a longitudinal member positioned in the slot and a blocker coupled to the screw head and the longitudinal member.

Abstract: This implantable orthopedic device comprises a support structure (2) provided with an orifice (3) delimiting a receiving housing (5) for a nut (6) intended to cooperate with a fixing screw (4). The housing (5) comprises an upper part (5a) and a lower part (5b), both parts being generally truncated sphere shaped and concentric to each other. On the other hand, the nut (6) comprises a peripheral contour (11) and the screw head (15) comprises a lower part (15b), also having a spherical contour, as well as an upper part (15a) provided with a thread (17).

Abstract: A clamping body for a pedicle screw assembly has an axial passage extending axially between first and second end portions thereof. The spine rod-receiving channel extends through the first end portion in a traverse direction with respect to the axial passage thereby forming upstanding leg portions of the clamping body and closed end portion of the spine rod-receiving channel. A material thickness reducing relief is provided in an outer surface of each one of the upstanding leg portions at a location between the closed end portion of the spine rod receiving channel and the first end portion of the clamping body whereby the a partial segment of the upstanding leg portions are frangibly detachable. A bridge member is frangibly connected between the upstanding leg portions at the first end portion of the clamping body. The bridge member spans across the spine rod-receiving channel.

Abstract: A bone anchoring device includes a receiving part for receiving a rod, the receiving part has a first bore coaxial with a longitudinal axis and a second bore, and an anchoring element having a first end for insertion into the bone and a second end positionable within a second bore, the anchoring element being movable relative to the receiving part in limited angular range about the longitudinal axis, the angles lying in a single plane. The bone anchoring device further includes a fixation element cooperating with the receiving part to lock the anchoring element relative to the receiving part. The anchoring element is pivotable relative to the receiving part around one rotational axis transverse to the longitudinal axis.

Abstract: A receiving part for coupling a rod to a bone anchoring element includes a receiving part body including a rod receiving portion having a channel for receiving a rod, and a head receiving portion for accommodating a head of a bone anchoring element, the head receiving portion having an open end and being flexible for inserting and clamping of the head; and a locking ring around the head receiving portion, wherein in a pre-locking position, a spring portion on one of the locking ring or the receiving part body engages a corresponding portion on the other one of the locking ring or the receiving part body, and the locking ring exerts a first force onto the head receiving portion, and wherein in a locking position, the locking ring exerts a second force greater than the first force onto the head receiving portion to lock the head therein.

Abstract: A dynamic bone anchor for anchoring a spine stabilization assembly which supports the spine while providing for the preservation of spinal motion. The dynamic bone anchor provides load sharing while preserving range of motion and reducing stress exerted upon the bone anchors and spinal anatomy. The dynamic bone anchor includes a deflectable post connected by a ball joint to a threaded anchor. Deflection of the deflectable post is controlled by a compliant sleeve. The force/deflection properties of the dynamic bone anchor may be adapted to the anatomy and functional requirements of the patient. When implanted the pivot point for the deflectable post is placed close to the instantaneous center of rotation of the spine. The dynamic bone anchor may be used as a component of a dynamic stabilization system which supports the spine while providing for the preservation of spinal motion.

Abstract: A pedicle screw for insertion into the pedicle portion of a vertebra and having at its exposed end a threaded rod connected in a generally parallel orientation to the longitudinal axis of the pedicle screw but laterally offset from the longitudinal axis of the pedicle screw. The threaded rod may be secured directly to the screw but is preferable provided with a collar that is captured by an enlarged screw head to seat, orient and retain the threaded rod in position. A locking arm and retaining nut are provided over the threaded rod for affixing a spinal rod to the pedicle screw substantially over and aligned with the longitudinal axis of the screw. A yoke may be provided in the collar also to receive and secure the rod. An alternate cap and clamping elements enable the incorporation of cross links between multiple screws and/or rods.

Abstract: An external fixator implant screw with an intercalated head, of which one embodiment for lag screw mode has a spherical head, and a partial thread. The spherical head in countersunk bone exerts concentric wide contact on insertion at various angles to surface. Optional canalization of central rod allows guide wire technique and optional mobility of head allows variable shaft length between head and thread. Another embodiment for use in basic implant mode, in a single bone fragment, at right angles to bone surface, has a conical head with limited basal contact on bone, the head being integrated to a solid rod and is fully threaded from head to leading tip. In both embodiments, the load transmission is renewable from outside in case of loosening, without reopening any wound. The implant is made of biocompatible material.

Abstract: The hinge mounting system according to the present invention is constituted of a link connector (10) comprising, on either side of a U-shaped opening (8), a first and a second vertical branch (11, 12) respectively cooperating through axes of rotation (13, 14) with a clamping element (15) enabling the linking rod (4) to be immobilized in translation and in rotation after it has been pivoted and locked above the opening (8) by a lock (16) elastically loaded by a leaf spring (29).

Abstract: A bone anchor comprises a screw having a threaded shank portion and a head portion, and a housing assembly. At least the threaded shank portion is formed from a titanium or titanium alloy and at least a portion of the housing is formed from a stronger material such as cobalt chrome. The housing assembly has a passageway extending therethrough and a proximal end and a distal end. A saddle is defined within the proximal end of the housing assembly and is configured to retain a portion of a rod therein. The distal end of the housing assembly is configured for securely engaging the head portion of the screw such that the screw is at least one of rotatable and pivotable with respect to the housing.