摘要:
The device comprises a slide (3) so profiled as to be insertable in a support (2) in a slidable and coaxial manner with respect to an elongate element (1) and in intimate contact with the latter. This slide has two lateral lips (5) adapted to cooperate with ramps for clamping the slide and formed in the support (2), the lips and the ramps being inclined to the axis of the elongate element (1). The lips (5) are advantageously rounded and define an intermediate constricted part thereby achieving a self-clamping of each lip (5) of the slide (3) in the associated ramp of the support (2). The device supports an extremely high assembly prestressing without deforming or breaking, even when the prestressing is increased in an exaggerated manner, this being achieved with an overall size which is smaller than a screwed assembly of elements of a cross-shaped structure. Various applications in particular in the connection of a spinal osteosynthesis rod with a pedicular anchorage element.
摘要:
This rod comprises a first cylindrical part, being a lumbosacral part (6), which is rigid in all directions, a second part, being a dorsal part (7), which is rigid in a frontal plane, in order to prevent scoliosis, and flexible in a sagittal plane, and a dorsolumbar transition zone (8) connecting the lumbar and dorsal parts and profiled in a progressive manner so that its thickness in the sagittal plane diminishes progressively and its width in the frontal plane increases progressively: this profile is such that the second moment of area of the transition zone remains substantially constant over its entire length. The profile, thus defined, of the transition zone has the aim of avoiding, to a great extent, the risks of breaking due to the fatigue in this zone, resulting from the various movements of the patient in a chair, in particular the flexion/extension movements in a sagittal plane, promoted by the rectangular profile of the dorsal part of the rod.
摘要:
The device comprises a slide (3) so profiled as to be insertable in a support (2) in a slidable and coaxial manner with respect to an elongate element (1) and in intimate contact with the latter. This slide has two lateral lips (5) adapted to cooperate with ramps for clamping the slide and formed in the support (2), the lips and the ramps being inclined to the axis of the elongate element (1). The lips (5) are advantageously rounded and define an intermediate constricted part thereby achieving a self-clamping of each lip (5) of the slide (3) in the associated ramp of the support (2). The device supports an extremely high assembly prestressing without deforming or breaking, even when the prestressing is increased in an exaggerated manner, this being achieved with an overall size which is smaller than a screwed assembly of elements of a cross-shaped structure. Various applications in particular in the connection of a spinal osteosynthesis rod with a pedicular anchorage element.
摘要:
The instrumentation comprises a pair of vertebral implants (1) provided with screws (4) for anchorage to two corresponding vertebrae located on each side of a damaged vertebra, and a plate (3) having two end portions (3a) for connection to the two implants, and equipped with means (6, 15) for fixing it to the implants. The end portions (3a) of the plate have a rounded periphery and the instrumentation comprises fixing screws (50) having heads (51) which are rounded so that their surface is flush with the surface of the plate when they are anchored in the apertures of the implant and the apertures of the end portion (3a) of the plate. This arrangement ensures that the ends of the plate (3) do not come into contact with the vertebral discs when the angular position of the plate (3) relative to the implants varies, and reduces the overall size of the instrumentation.
摘要:
The instrumentation comprises a pair of vertebral implants (1) provided with screws (4) for anchorage to two corresponding vertebrae located on each side of a damaged vertebra, and a plate (3) having two end portions (3a) for connection to the two implants, and equipped with means (6, 15) for fixing it to the implants. The end portions (3a) of the plate have a rounded periphery and the instrumentation comprises fixing screws (50) having heads (51) which are rounded so that their surface is flush with the surface of the plate when they are anchored in the apertures of the implant and the apertures of the end portion (3a) of the plate. This arrangement ensures that the ends of the plate (3) do not come into contact with the vertebral discs when the angular position of the plate (3) relative to the implants varies, and reduces the overall size of the instrumentation.
摘要:
This device comprises a connection element (4) between a rod (1), or other longitudinal implant, and a bone anchorage screw (3) in the degenerative vertebra. This connection element (4) includes a ring (8) so dimensioned that the rod (1) is capable of extending therethrough. The ring is provided with screws (14) for clamping to the rod (1) and is radially extended by a cylindrical arm (9) adapted to be secured to the bone anchorage screw (3) and to be clamped on the screw. The arm (9) and the ring (8) constitute a unit in one piece. The invention enables the surgeon to avoid having to produce additional deformations of the rod (1) when it is in presence of non-aligned pedicles by leaving to the surgeon complete liberty as to the position of the two axes of the bone anchorage screw (3) and of the rod (1). The invention further contemplates using the lateral connection element to facilitate contouring the longitudinal implant within the patient, or in situ to segmentally and globally correct spinal deformities in all degrees of freedom.
摘要:
The hook (32) comprises a body (33) and a laminar portion (37) which is suitably profiled and adapted to penetrate a foramen opening at the base of the occiput against which it bears. The body is arranged to receive an osteosynthesis rod or plate and has a plane of symmetry (P). The laminar portion (37) has a curvature adapted to the thickness of the occipito-cervical shell and is inclined relative to one side or the other of the plane of symmetry (P) so as to be adaptable to the anatomy of the edge of the occiput in the region of the foramen. This inclination may be for example substantially 45°. This asymmetry of the laminar portion (37) relative to the body (33) of the hook (32) enables the surgeon to avoid having to previously remove a piece of the edge of the occiput of the patient and consequently damage the occiput.
摘要:
The instrumentation comprises two separate similar parts, namely a right part (1) and a left part (2), each formed by a cervical rod (3) having asperities and an elongate occipital plate (5) formine one piece with the rod and extending it toward the occiput (6) in the position of use, and adjustable means for anchoring the rod to the vertebrae and the plate to the occiput. Each part is so preangulated and shaped as to be adapted to the anatomy of the occipito-cervical connection. Each rod (3) has two rectilinear sections making therebetween an angle of between about 70 and 90°, one of the sections being connected to the occipital plate (5), which is bent so as to correspond to the curvature of the occipital shell. The invention permits conveniently adapting the distance between the rods (3) to the anatomy of the patient and reduces the overall size of the instrumentation, which enables projections under the skin of the occiput to be considerably reduced.
摘要:
The instrumentation comprises for each lumbar vertebra (L5), two pedicular screws (1) having two screw threads (9, 11), one (9) of the screw threads corresponding to the region of penetration of the screw in the pedicle, two rods (2) having asperities respectively associated with a pedicular screw and secured to the latter by connection elements (3) provided with elements for clamping the rods. Each connection element (3) is in one piece and the screw thread (9) corresponding to the region of penetration of the screw in the pedicle terminates in an annular shoulder (16) against which the connection element bears which is separated by a smooth part (15) from the screw thread (11) outside the region of penetration in the pedicle. This instrumentation permits both returning the slipped vertebrae rearwardly and pivoting it in the desired direction of rotation, it being possible to carry out the derotation action slowly and by controlling the movement so that the surgeon achieves on the whole in the two movements an excellent precision in the repositioning of the vertebrae relative to the neighbouring vertebrae.