FR2738143A1 - Modular surgical implant for stabilising vertebrae - Google Patents

Abstract

The implant consists of wedges (A), whose lateral portions include apertures oriented perpendicularly to each other and configured to receive the head of a pedicular screw (12) and a linking shaft (14). Modular spacers (B) are articulated on the linking shaft between adjacent wedges. The spacers include a longitudinal passage which receives a connecting shaft or wire of steel. The connecting and linking shafts may be formed of material with different degrees of elasticity, allowing selection of the overall degree of elasticity of the assembly according to the requirements of individual cases.

Description

 SURGICAL IMPLANT FOR VERTEBRAL STABILIZATION.

The present invention relates to a spinal stabilization implant.

It also relates to an intervertebral surgical prosthesis consisting of a plurality of surgical implants.

The invention finds an advantageous application in orthopedic surgery, in particular during spinal affections, which can be found for example in patients whose discs are deteriorated.

Various surgical devices intended to treat deformities of the spine are known from the state of the art; so we can cite two large families in known devices
wire rigid or semi-rigid systems intended for arthrodesis.
consist of metal plates and bars attached to
vertebrae using screws.

} flexible stabilization systems, which split into a system
with pedicle implant (patents 8901445, 9101288) and system
with interspinous wedges (EP.AO patents 322,334 and 392,124, or
FR.A.2 693 364.)
In addition to these two major families, there are two devices (patents 94 00457 and 94 15290.) which respectively offer
r a flexible system whose pedicle screws could be used to
anchoring both rigid and flexible elements, and therefore
ability to easily switch from flexible ring stabilization
ligaments on screws, arthrodesis on these same screws. The
elements are rings made of synthetic fibers or axes
rigid in the form of plates or bars.

t an evolving system composed of thorny rings forming
fitting one on top of the other a coherent assembly.
homogeneous made of flexible rings depending on the material used,
will be made more or less rigid by adding blades or bars
introduced on either side of the thorny, in the cavities
provided for this purpose in the rings. This system allows
intervertebral stabilization in flexion, extension and
On the other hand these rings present in certain cases of
"ears" which cover the pedicles or to be fixed there
by screw or on a rod secured to the pedicles by screw or
hooks and used as "handrail".

We exclude from our comments the system developed in patent DE.A.28 21678; indeed, these are traction or distraction elements of the "shock absorber" type with a very high level of micro-mechanical performance and a great risk of wear. These elements are fixed to the transverse processes by the intermediate jaw grips them.In order to avoid disengagement of the sleeves (jaws) they can be connected by a flexible rod in pairs on the same vertebra.

The technical problem to be solved by the present invention is to
propose a simple and modular intervertebral space stabilization implant, in order to limit the deflection of the vertebrae
during flexion-extension movements, and to check their sagittal and frontal rotational stability.

The solution to the technical problem posed consists, according to this
invention, in that said implant is composed of interspinous wedges held in place between the spinous processes; these wedges are coupled with, at the pedicle levels, props which by successive cooperations will allow adaptation to the desired stability.

Thus the intervertebral surgical implant consists of
d the hold having a depression where the thorny finds accommodation,
continues laterally and attaches to the pedicles by
through screws or hooks.

This wedge can be armed, for example with a blade, a rod
or an artificial ligament.

+ the props which are inserted between the pedicles of each of the
vertebrae, and are fixed there on screws or by means of
hooks, are made of more or less rigid or flexible materials depending on the choice of the surgeon. They have if necessary a
through cavity for the passage of an axis (rod, wire, lig ...)
which plugs in the successive props and the heads of the screws
pedicular will give homogeneity to the assemblies, which we
can vary the travel allowed by simple choice
of the material or by more or less strong compression of
the stacking of the props and screws. Thus the rod or the placard wire,
in shape memory alloy, artificial fibers or
composite can be stretched more or less inside one or
several conduits and fixed at each end of the device,
we will thus obtain a compression setting of the assembly and a
homogenization, which will be a function of the rigidity sought by
the surgeon in the face of such or such cases of degenerative spine or
traumatic.

A characteristic of the invention is to propose a wedge which in the central part supports the thorny of a vertebra, and in lateral parts are fixed to the pedicles; it may contain a conduit connecting the lateral parts to each other passing over the thorny plant.

The description which follows with reference to the appended drawings, given by way of nonlimiting examples, will make it clear what the device according to the invention consists of and how it can be produced.

Figure 1 is a front view of the implant, according to a first embodiment.

Figure 2 shows a front view of two shims with its passages for screws and rods.

Figure 1 shows a system (10) composed of wedges (121, 122, 123), stays <221 to 224), pedicle implants C12), 1 1 and retaining rods (14). pierced with conduits (16, 16 ') for the passage of a rod (14) or any other means allowing the rings to be kept in a coherent system, or even reinforcing rods; cavities (201) allow the fixing of the wedges to the vertebrae by pedicle screws (12). The stays are pierced with conduits (19) for the passage of reinforcing elements or supports, such as a pin.

Figure 2 illustrates the fact that a block (121) can present several solutions for the passage of the head of a pedicle screw, it can be internal (A) or external (B) to the block with a frame (450) .

Claims (5)

REVEIDICAI IONS. 1 Surgical implant for vertebral stabilization, characterized in that said implant consists of wedges, the lateral parts of which have mixed conduits for receiving the head of the pedicle screw and a holding rod approximately perpendicular to the axis of the screw. 2: surgical implant according to claim 1, characterized in that modular stays are articulated between the fastenings of the wedges on the pedicles. 3 surgical implant according to claims 1 and 2, characterized in that the stays have a longitudinal cavity to receive a rod, a steel wire ... 4 surgical implant according to claims 1 to 3, characterized in that the rod, bar, wire ... are made of more or less flexible or rigid material, which can vary the elasticity by bandaging at will. 5 surgical implant according to claims 1 to 4, characterized in that the wedge is pierced so as to allow the passage of a frame, which can serve as an anchoring means to the pedicles.