Abstract: A bioabsorbable interference screw having a tapered profile which extends along substantially the entire length of the screw. The tapered profile makes the screw easy to insert while providing superior fixation resulting from a progressively increasing diameter. Upon insertion, the screw engages cortical bone at the back end of the bone tunnel and fills all but 5-10 mm. of the tunnel, thereby providing increased fixation strength while also promoting fast healing. The screw includes a head provided with a specially designed drive socket with radially extending slots at its outer end for receiving corresponding protrusions on the shaft of screwdriver. The drive socket optimizes the torque capacity of the screw. To maintain wall thickness, the socket has a taper corresponding to the tapered outer profile of the screw. The taper of the socket also permits easy insertion of the tip and shaft of the driver into the screw.

Abstract: A cardan shaft structure with tightness adjustable functions has a through-hole passing through spheres located at both ends of the cardan shaft body, and a taper socket respectively installed into the opening end of each sphere. A bolt is inserted into both spheres and the body, fixed and locked together in conjunction with a nut. The cardan shaft structure works together with two clamping components wrapping around the spheres. When the sphere is being pushed against (or freed from) the inner wall of the clamping component by tightening (or loosing) the bolt so as to make the sphere either expand (or recover), the angle displacement of the clamping component becomes adjustable accordingly.

Abstract: Self-compressing screws, especially self-threading screws, include a screw shaft having an axis of revolution, the screw shaft being provided with two threads that are centered on the axis of revolution, and a first envelope in the form of a rotary hollow cylinder defined by the thread, between the base and the tip of an individual thread section, fitting entirely inside the second envelope in the form of a rotary hollow cylinder defined by the thread, between the base and the tip of an individual thread section. A pitch P11 of the thread is smaller than a pitch P22 of the thread. A method of applying the screw for joining two bone segments is also provided in order to perform an osteosynthsis operation between the two bone segments.

Abstract: A radially expandable sheath is provided having a substantially closed distal end with at least two sidewalls extending proximally therefrom and defining a central lumen. Each sidewall can have a substantially concave outer surface adapted to seat a graft member, and each side wall is at least partially separated by a longitudinally oriented slot that extends from a proximal end along a substantial length of each sidewall. The slot preferably terminates at a position just proximal to the distal end. The device can also include a sheath expander that is adapted to be disposed in the central lumen of the radially expandable sheath and that is configured to flex the sidewalls to radially expand the sheath so as to fix a graft member within a bone tunnel.

Abstract: System, including methods and apparatus, for provisionally bracing an external fixator while the external fixator is reconfigured.

Abstract: A polyaxial pedicle screw assembly incorporates a concave portion on a receiver which mates with a convex surface on a head of the screw to form a ball joint. The radius of at least a portion of the concave surface is less than a radius of the mating convex portion whereby to create an interference fit.

Abstract: An artificial spinal implant is disclosed which when placed between two adjacent vertebrae directly participates and is incorporated in the ensuing fusion. Instrumentation and procedure is also disclosed.

Abstract: One or more anchors are engaged intravertebrally for attachment of one more constructs thereto to correct or treat spinal conditions or deformities. Methods for inserting the anchors are also provided along with constructs for attachment to the anchors.

Abstract: An implant for osteosynthesis used in the stabilization of fractured bone of the mandible. The plate consists of apertures through which the plate is secured to bone using surgical screws. The apertures are connected by (a) two lateral bar sections running approximately parallel to the long axis of the mandible and (b) two cross bar sections intersecting each other near the centroid of the plate and at acute angles to the lateral bar sections. The plate design can be modified to accommodate patient anatomy depending on the type of bone it is designed to stabilize. Design and size parameters of the fixation plate can be customized to each individual patient using a customization software application to determine the least invasive fixation plate that will provide adequate functioning in stabilizing the bone fracture to a degree that will allow safe bone healing. The invention includes a method of design of osteosynthesis plates using shape optimization for different types and locations of fractures.

Abstract: A connecting device is provided for use in orthopedic surgery, for example to connect a spinal rod and a vertebral screw or hook. The connector generally includes a receiver member for receiving an elongated member, and an grommet member for receiving a bone fixation member. The grommet member is inserted into the receiver member so that the receiver member and grommet member are rotatably connected. One or more disks may be placed between the receiver member and grommet member to assist in locking the device.

Abstract: A biodegradable interference screw for directly affixing a transplant to a bone, the interference screw being provided with at least one longitudinal groove designed to co-act with a tool for insertion of and if necessary, removal of the interference screw from an opening provided in the bone to receive both the transplant and the interference screw.

Abstract: The present invention provides for a screw and rod fixation assembly for fixing a screw and, optionally, a rod. The screw and rod fixation assembly includes a screw, fixing mechanism, a substantially annular ring, rod seating mechanism, and locking mechanism. The present invention also provides for a fixing mechanism for fixing a screw, wherein the fixing mechanism further includes an inner surface wall having a gripping portion and a non-gripping portion. Further, the present invention provides for a substantially annular ring for guiding and providing mechanical and frictional force to a screw head. Additionally, the present invention provides for a rod seating mechanism operatively engaged to the screw head and including at least one flexible portion capable of being compressed against a portion of a rod therein. Finally, the present invention provides for a locking mechanism for engaging the rod and the rod seating mechanism.

Abstract: There is disclosed a radially expandable knotless tissue anchor including an expandable outer member defining a bore and an inner member slidably positioned within the bore. Relative longitudinal movement of the inner member relative to the expandable member causes a portion of the expandable member to expand radially outwardly. The tissue anchor further includes a length of suture material having a first end affixed to a distal end of the inner member and a second end preferably affixed to a suturing needle. A transverse bore is provided adjacent the distal end of the inner member. There is also disclosed a method of knotlessly anchoring a section of tissue to a section of bone having a bore drilled therethrough. The method includes passing the suture through the tissue and positioning the expandable member and a section of tissue within the interior of the bore drilled in bone.

Abstract: A suture anchor is provided having a body with at least one suture-receiving channel that extends distally from a proximal end of the body. The suture-receiving channel can include a cavity formed in a distal-most end of the body, or it can terminate at a transversely-extending bore formed through the body. The suture anchor can also include a suture loop that is positioned within the suture-receiving channel and cavity or bore, and that includes a proximal portion that extends proximal of the proximal end of the body.

Abstract: A connector comprising at least one pair of apertures for receiving a fastener, such as a screw, a load bearing filament extending continuously along a predefined circuitous path which extends between and around each of the apertures of said pair of apertures. The load bearing filament extends around each aperture to define multiple aperture forming strands of said load bearing filaments. The multiple aperture forming strands of the load bearing filament are bound together around each aperture by binding filaments in order to constrain relative lateral movement between the aperture forming multiple strands and to define the shape of each aperture.

Abstract: A bioabsorbable, cannulated tissue tack having an oblong head is used in sutureless soft tissue fixation to bone, particularly in arthroscopic shoulder surgery. A plurality of ribs are formed along the shaft of the tack. Repair of the glenohumeral joint is performed by installing the tack through a hole formed through the soft tissue of the labrum and into the cancellous bone of the glenoid rim. Aligning the oblong head of the tack lengthwise along the glenoid rim provides a low profile that avoids articular impingement on the tack head.

Abstract: A method and apparatus for repairing the femur. A connector is provided having a claw-like member to engage with the greater trochanter. Along the body of the connector are a plurality of cable apertures and cable screws to receive and engage with cables that loop around the femur. Along the inferior end of the connector are bone screw slots and bone screws engaging the connector with the femur. The bone screws provide added support to the re-attached greater trochanter and provide support for periprosthetic fractures. The connector may be used to re-attach the greater trochanter by impacting a connector onto the greater trochanter, positioning the greater trochanter onto the femur, passing cables around the femur and through the connector, tensioning the cables to provide engagement between the greater trochanter and the femur, and attaching the connector to the femur using at least one bone screw.

Abstract: A supplemental spine fixation device and method is used in association with a primary spine fixation device. The supplemental spine fixation device includes a guide and spacer for distracting apart adjacent spinous processes and the device has hook members which hook about the first and second spinous processes. With the spinous processes distracted and the hook members about the spinous processes, the hook members can be rigidly secured to a hub in order to rigidly affix the spinous processes about the spacer. The rigidity between the spinous processes assures that the vertebral bodies will be held rigidly in place in order to promote bone growth and fusion. Further additional freedom of movement between the spacer and hub is accomplished with the spacer being pivotably mounted relative to the hub. The hooks have a tissue distracting lead-in guide for allowing the hooks to be easily urged between spinous processes.

Abstract: Disclosed are medical prosthetic devices or medical implants which exhibit improved biocompatitibly. The devices or implants include a metal material, e.g. titanium, in which the metal surface parts are coated with a corresponding hydride material that contains one or more biomolecule substance. This biomolecule substance may contain one or more biologically active molecules, e.g. bio-adhesives, biopolymers, blood proteins, enzymes, extra cellular matrix proteins, extra cellular matrix biomolecules, growth factors and hormones, peptide hormones, deoxyribonucleic acids, ribonucleic acids, receptors, enzyme inhibitors, drugs, biologically active anions and cations, vitamins, adenosine monophosphate (AMP), adenosine diphosphate (ADP), adenosine triphosphate (ATP), marker biomuolecules, amino acids, fatty acids, nucleotides (RNA and DNA bases), or sugars.

Abstract: The invention relates to a tissue anchor which is an open helix of biocompatible material having a slope of from 0.5 to 10 turns per centimeter, a length from 3 to 75 millimeters, a diameter of from 1.5 to 11 millimeters, and an aspect ratio of from about 3 to about 5 to 1. The anchor can have a head which is capable of securing or clamping tissue together, such as holding a suture to secure a ligament or tendon to bone. The anchor can also have a head which causes an inward, compressive loading for use in fastening bone to bone, orthopedic plates to bone, or cartilage to bone. The head may be an integral member and may include a self-reinforcing wedge which joins the helix to the head. Further, the elongate member, or filament that forms the helix may have a tapering diameter along its length.

Abstract: The present invention provides a cervical plate with backout protection. In particular, a bushing residing in each of a plurality of through holes has a bottom edge that aligns with a protrusion on a screw head. The bottom edge aligning with the protrusion inhibits reverse threading or backing out of the bone screw.

Abstract: A device for external fixation of a fracture of the proximal end of the ulna includes an frame having a distal elongated portion extending below the ulna, holding a number of pins extending upward into the shaft portion, and a proximal portion extending rearward, and upward around the proximal end of the ulna, holding a medullar pin extending into a medullar channel and a number of pins extending into fragments of the fractured ulna.

Abstract: A flanged interbody spinal fusion implant for insertion at least in part between adjacent vertebral bodies has opposed upper and lower surfaces adapted to contact each of the adjacent vertebral bodies from within the disc space, a leading end for insertion between the adjacent vertebral bodies, and a trailing end opposite the leading end. The trailing end has a height greater than the maximum height of the disc space forming a flanged portion adapted to overlie a part of the anterior aspects of the vertebral bodies adjacent and proximate the disc space to be fused. The flanged portion has at least two bone screw receiving holes, at least one each adapted to overlie each of the adjacent vertebral bodies at least in part. The implant has at least one locking element to lock one or more of the bone screws inserted in the bone screw receiving holes. Instrumentation for inserting the implant, forming screw holes in the vertebral body, and for locking the locking elements are disclosed.

Abstract: An apparatus for the correction of wall chest deformities, such as “Pectus Carinatum”, comprising: a bar (10) having a flattened cross-section, having a minimum bending strength according to the values defined by ASTM F382-95, plates (20) having a slot (21) in the medium portion so as to fit the corresponding end of the bar (10) and peripheral holes (23) for securing the bone parts. The bar ends comprise planar grooves (11–11?) determining the wall thickness substantially similar to the height of the slot (21) of the plate (20). The wall of the grooves (11–11?) has aligned holes (13) in order to form with the respective plate (20) and by using screws (30), a fixed removable attachment that allows the axial registration of the bar (10). Method for the correction of Pectus Carinatum using said apparatus in order to achieve a normal anatomic shape of the chest wall.

Abstract: The present invention is directed to a transconnector for coupling first and second spinal fixation rods or other elongate fixation elements. The transconnector includes a male member, a female member, and a locking member. The male member has a body with a linking element (such as a hook) associated with the lateral end for receiving one of the fixation elements, and a projection on the medial end. The projection includes a recess defined by lateral and medial walls. The female member has a body with a linking element associated with the lateral end for receiving the other fixation element, and a cavity with an opening on the medial end for receiving a portion of the male member projection. The locking member secures the position and orientation of the male member projection portion in the cavity in order to accommodate different separation distances and orientations between the first and second fixation elements.

Abstract: The present invention is a specialized orthopedic implant having an exterior surface for engaging bone. The surface comprises arrayed projections having at least one forward facing facet directed at least in part toward the leading end of the implant and at least one rearward portion directed at least in part toward the opposite trailing end of the implant. Each of the forward facet and rearward portion has a length and a slope. The length of the forward facet is longer than the length of the rearward facet. The slope of the rearward facet is steeper than the slope of the forward facet. The surface projections also have opposed side facets directed generally toward the sides of the implant. The side facets are located between the forward facet and rearward facet and converge toward each other in a direction away from the base of the surface projections. The surface may also include projections having left and right forward side facets and a rearward facet.

Abstract: A spinal fixation system includes a rod, an anchor, and a clamp assembly. The anchor is adapted to engage a bone. The clamp assembly secures the anchor to the rod. The clamp assembly includes a first portion with first and second flanges for receiving the anchor. A compressible ball is carried by the second portion of the clamp assembly. The ball has a through hole receiving the rod. The through hole is defined by a generally cylindrical inner surface having at least one relieved channel. The first and second flanges include first and second opposing surfaces, respectively. The first and second opposing surfaces are normally angled relative to one another. A nut which threadably engages an upper shaft of the fastener is tightened to draw together the first and second flanges to a position in which they are generally parallel to one another. At least a portion of the through hole tapers from one of the first and second ends towards a center of the ball.

Abstract: The present invention relates to apparatus and methods for stabilizing and or maintaining adjacent bone portions in predetermined desired relationships and for constraining one, two or three-dimensional motion and/or rotation of the adjacent bone portions. More particularly, the present invention relates to a magnetic apparatus with at least two magnetic arrays, each of which may include any number of magnets arranged in a predetermined manner and each magnetic array generating a magnetic field therearound. Once implanted and secured to the adjacent bone portions, the apparatus provides interacting magnetic fields in the area of the bone portions and transduces magnetic energy into mechanical energy and mechanical energy into potential magnetic energy, thereby reproducing functionally anatomic and/or anatomically advantageous arrangement of the bone portions.

Abstract: The present invention provides a unique and novel internal fixation for fixing an intracapsular and extracapsular including substochanteric fracture of a femoral neck while using minimal invasive procedure. The fixation comprises a hollowed or full tubular member having a sharp end and a blunt end that is adapted to be implanted while slightly crossing the fracture line. The tubular member is provided with three passages that extend from the sharp end to the blunt end. Three lag screws are adapted to pass through the passages and extend outwardly beyond said sharp end while thread that is provided in the lag screws so as to allow compression of fragments of the bone. The lag screws are provided with screw heads so as to prevent the screws from being fully inserted into the passages and through the trochanteric cortical bone.

Abstract: A screw formed of cortical bone for use in the human body with an implant having a screw hole for receiving at least a portion of a screw therethrough, includes a shaft with a thread along at least a portion of its length. The thread has an outer diameter dimensioned to pass through the screw hole in the implant. The trailing end of the screw is configured to cooperatively engage at least a portion of the screw hole of the implant so as to prevent the screw from linear motion along the mid-longitudinal axis of the shaft in a direction opposite to the direction of insertion when the screw is threaded through the screw hole to attach the implant to a bone portion of the human body. The screw is formed substantially of cortical bone of a single cortical thickness.

Abstract: A low profile orthopedic device is used to fix and stabilize bones to correct anomalies in skeletal structure occurring naturally or by trauma. Bone screws are screwed into bones by application of torque. Clamps are movably attached to the screws. Each clamp includes a compression ring. A connecting rod connects several screws through slots in the clamps. The clamps are tightened to hold the rod and the heads in a pre-selected position by linear movement of the compression rings.

Abstract: An implantable, time-released substance delivery device includes a casing having an exterior surface, and a number of pores disposed on the exterior surface of the casing. The time-released substance delivery device further has an interior chamber disposed within the casing, and a number of excretion tubes disposed within the casing. Each of the excretion tubes fluidly connects the interior chamber to one of the pores.

Abstract: An innovative bone anchor and methods for securing soft tissue, such as tendons, to bone, which permit a suture attachment that lies entirely beneath the cortical bone surface. Advantageously, the suturing material between the soft tissue and the bone anchor is secured without the need for tying a knot. The suture attachment to the bone anchor involves the looping of a length of suture around a pulley within the bone anchor, tightening the suture and attached soft tissue, and compressing the suture against the bone anchor. The bone anchor may be a tubular body having a lumen with a locking plug that compresses the suture therein. The pulley may be a pin located near a distal end of the tubular body around which the length of suture is looped. Alternatively, a pulley may be a bridge portion of the tubular body between two spaced apertures in the wall of the body. The locking plug may include a shaft and an enlarged head that interferes with the tubular body to provide a positive stop.

Abstract: An artificial facet joint includes a spinal implant rod and a connector. The connector includes a screw and a rod connecting member having structure for engagement of the rod. The rod connecting member is pivotally engaged to the screw. The rod may also be held slideably within the connector enabling the rod to be moved relative to the connector.

Abstract: This invention provides novel nanofibers and nanofiber structures which posses adherent properties, as well as the use of such nanofibers and nanofiber comprising structures in the coupling and/or joining together of articles or materials.

Abstract: A radially expandable knotless tissue anchor including an expandable outer member defining a bore and an inner member slidably positioned within the bore. Relative longitudinal movement of the inner member relative to the expandable member causes a portion of the expandable member to expand radially outwardly. The tissue anchor further includes a length of suture material having a first end affixed to a distal end of the inner member and a second end preferably affixed to a suturing needle. A transverse bore is provided adjacent the distal end of the inner member. A method of knotlessly anchoring a section of tissue to a section of bone having a bore drilled therethrough includes passing the suture through the tissue and positioning the expandable member and a section of tissue within the interior of the bore drilled in bone. Expansion of the expandable member secures the suture between the expandable member and the bone to thereby secure the attached tissue to bone.

Abstract: A distraction device enabling management of the evolving deformation of the trunk of a child during growth. The device is easy to implant on account of its compact shape and includes two rods which can be bent and deformed on the ends thereof and which are mounted on a central adjusting member which is provided with a small hole for engaging a small tool that is designed to adjust the distance separating the elements for attachment to the bone. The inventive device can be locked in a position which is determined by the tightening of two screws which are disposed on the adjusting device.

Abstract: To change a spatial relationship between two or more bones in a patient's body, a wedge member is moved into a joint between the bones. As the wedge member enters the joint, pivotal movement occurs between the bones to change the orientation of the bones relative to each other. The wedge member may have a circular cross sectional configuration and be moved into the joint by rotating the wedge member about an axis which extends between a thin leading edge portion and a thick trailing edge portion of the wedge member. Alternatively, the wedge member may have a cam-shaped configuration and be rotated through less than a revolution to apply force against the bones. The wedge member may have a porous construction which enables bone to grow through the wedge member and immobilize the joint. The wedge member may be coated with and/or contain bone growth promoting material. The wedge member may be connected to only one of the bones or may be connected to two adjacent bones.

Abstract: Disclosed are methods of spinal fixation involving application of a liquid medium which cures, hardens, polymerizes or otherwise serves to bind adjacent vertebrae together. The fixation which results from this binding may be temporary or essentially permanent in duration, and may be used to treat conditions or disease of the spine, such as inflammation, instability or fracture. In a preferred embodiment, the liquid medium comprises a low viscosity cyanoacrylate-based adhesive.

Abstract: A bone fixation assembly including a coupling element having an inner surface defining a first bore coaxial with a first longitudinal axis, and a second bore coaxial with a second longitudinal axis, whereby the second longitudinal axis intersects the first longitudinal axis. The coupling element has a seat adjacent the lower end of the coupling element, the seat being defined by the inner surface of the coupling element. The assembly includes an anchoring element assembled with the coupling element, the anchoring element having a first end for insertion into bone and a head spaced from the first end, the head being in contact with the seat of the coupling element. The assembly provides sufficient angulation between adjacent anchoring elements securing a common orthopedic rod, and is particularly useful for assemblies mounted in spines having abnormal curvatures and in the cervicothoracic region of the spine.

Abstract: A prosthesis assembly replaces all or a portion of a caudal portion of a left natural facet joint (i.e., a left superior articular process) and all or a portion of a caudal portion of a right natural facet joint (i.e., a right superior articular process) on a vertebral body. The prosthesis assembly has a left prosthesis body accommodating fixation to the vertebral body at or near a left pedicle and without support by a lamina. An artificial left facet joint structure is carried by the left prosthesis body and is adapted and configured to replace all or a portion of a caudal portion of the left natural facet joint. The prosthesis assembly also has a right prosthesis body accommodating fixation to the vertebral body at or near a right pedicle and without support by a lamina. An artificial right facet joint structure is carried by the right prosthesis body and is adapted and configured to replace all or a portion of a caudal portion of the left natural facet joint.

Abstract: A graft ligament anchor comprises a graft ligament engagement member disposed in an opening in a bone, the graft ligament engagement member being arranged to receive a graft ligament alongside the engagement member, and a locking member for disposition in the opening, and at least in part engageable with the graft ligament engagement member. Movement of the locking member in the opening causes the locking member to urge the engagement member, and the graft ligament therewith, toward a wall of the opening, to secure the graft ligament to the wall of the opening.

Abstract: A subcutaneously implantable distraction device comprises a first arm, having a first skeletal connector for attachment to a first skeletal component at a first location. A second arm has a second skeletal connector for attachment to a second skeletal component at a second location. The first and second arms are slidably moveable with respect to each other. A fluid actuator is associated with each of the first and second arms to apply a separating force between the arms to slidably move at least one of the arms relative to the other.

Abstract: Insertion instruments and a main body assembly and a universal wing to be inserted are provided, along with methods of using these instruments for the insertion of the spinal implants in patients to relieve the symptoms of, for example, spinal stenosis, injuries, and degenerative diseases of the spine. The instruments are simply designed and can be disassembled, making cleaning and sterilization easy and convenient. The instruments are designed to engage with and disengage from spinal implants easily, and use of the instrument in spinal implant surgery can be carried out with minimal surgical intervention and does not require general anesthesia. The main body assembly and the universal wing are designed to conveniently be secured to the insertion instruments.

Abstract: A bioabsorbable interference screw having a tapered profile which extends along substantially the entire length of the screw. The tapered profile makes the screw easy to insert while providing superior fixation resulting from a progressively increasing diameter. Upon insertion, the screw engages cortical bone at the back end of the bone tunnel and fills all but 5-10 mm. of the tunnel, thereby providing increased fixation strength while also promoting fast healing. The screw includes a head provided with a specially designed drive socket with radially extending slots at its outer end for receiving corresponding protrusions on the shaft of screwdriver. The drive socket optimizes the torque capacity of the screw. To maintain wall thickness, the socket has a taper corresponding to the tapered outer profile of the screw. The taper of the socket also permits easy insertion of the tip and shaft of the driver into the screw.

Abstract: A biodegradable fixation element is provided for anchoring a transplant on bone. A rigid body is made of a biodegradable material, said body having an outer side and a hollow interior surrounded by a wall of said body. Numerous perforations are provided in said wall of said body for allowing growth of bone material into said interior of said body via said numerous perforations. It is proposed that the perforations are formed between said anchoring members and said perforations are formed as holes passing through said wall of said body (FIG. 1).

Abstract: A surgical distraction device is provided for applying extending or tensioning force non-invasively to a patient's skeleton or to an implant which comprises anchoring means for attaching first and second components of the device to a bone or to adjoining bones, said components being connected by a linkage of an extendible length, a magnet connected to the linkage via a reduction gearbox and actuating means located externally of the patient for generating a moving or varying electro-magnetic field, thereby causing the magnet to rotate and the linkage to be extended.

Abstract: The invention relates to a vertebral fixing device suitable for being mounted on a vertebra presenting a posterior wall and two side walls from which there project ribs and/or transverse processes. The device comprises: an elongate transverse part (16) presenting two substantially symmetrical opposite ends (18, 20), said transverse part (16) being suitable for being placed against said posterior wall (51) of said vertebra, each of said ends (18, 20) being situated facing a rib and/or a transverse process (52, 54); at least two clamp-forming adjustable connection elements (26, 28, 42, 44) suitable for being connected to each of said two ends (18, 20) respectively, said ribs and/or transverse processes (52, 54) being suitable for being engaged in said adjustable connection elements (26, 28, 42, 44) in such a manner as to hold said elongate transverse part (16) in a fixed position against said posterior wall (51) of said vertebra.

Abstract: The present invention generally provides a polyaxial fixation device having a shank with a spherical head formed on a proximal end thereof, and a receiver member having an axial passage formed therein that is adapted to polyaxially seat the spherical head of the shank. The polyaxial bone screw further includes an engagement member that is adapted to provide sufficient friction between the spherical head and the receiver member to enable the shank to be maintained in a desired angular orientation before locking the spherical head within the receiver member.

Abstract: An orthopedic device having a support structure provided with at least an orifice for a fixing screw associated with a nut; the head of the screw to be pressed on one side of the support, and the nut adapted to be pressed on the other side of the support, in a housing enabling its being integrated at least partly, so as to enable the support structure to be clamped between the screw head and the nut when the screw body has been completely screwed in the receiving bone material. The implantable device includes elements for maintaining the nut in its housing opposite the orifice, and elements for locking the nut in rotation. The contours of the housing and of the nut are dimensioned to provide at least one degree of freedom to the nut in the housing enabling self-centering of the screw and nut.