Modular vertebral stabilizer

Abstract

A stabilizer device (1) for the spinal column, comprising first engagement means (4) and second engagement means (5), which are adapted to be connected to each other by a rod-like element (8), the first and second engagement means (4, 5) being adapted to be fitted on first and second pedicle screws (2, 3), which are adapted to be in turn inserted in two adjacent vertebrae, the first and second engagement means (4, 5) being fixable on the pedicle screws (2, 3); the first and second engagement means (4, 5) accommodate bearing means (20), which are adapted to rotate within the first and second engagement means (4, 5) and to be fitted on the pedicle screws (2, 3), in order to allow the fitting of the first and second engagement means (4, 5) on the pedicle screws (2, 3).

Description

TECHNICAL FIELD[0001]The present invention relates to a modular vertebral stabilizer. More particularly, it relates to a modular vertebral stabilizer that is adapted to connect at least two adjacent vertebrae to each other by using at least two connecting elements which allow some certain limited movement to the vertebrae.BACKGROUND ART[0002]As is known, many pathologies related to the functionality of the spinal column are treated by total or partial immobilization, particularly with a technique known as “intervertebral arthrodesis”, with the aid of connection means and / or with the addition of portions of bone tissue which join such adjacent vertebrae.[0003]Vertebral stabilization devices of the static and dynamic types are known in the art and have a screw that is adapted to be connected to a vertebra, and rigid elements or elements that have a limited mobility and have two ends which are jointly connected to the two screws connected to two adjacent vertebrae.[0004]In particular, ...

AI Technical Summary

Benefits of technology

[0012]The aim of the present invention is to provide a device for stabilizing the spinal column which allows transverse connection between adjacent vertebrae, allowing different angles between pedicle screws inserted in adjacent vertebrae.

[0013]Within this aim, an object of the present invention is to provide a stabilizer device that can be assembled separately from the spinal column and then fitted onto said spinal column with reduced invasiveness for the patient.

[0015]Another object of the present invention is to provide a stabilizer device that is highly reliable, relatively simple to provide and at competitive costs.

Problems solved by technology

However, this stabilizer has a drawback, due to the fact that it is directly assembled locally on the spinal column after inserting the screws in the vertebrae, with open surgery in a space that is close to the vertebra.

Therefore, the surgical procedure that makes it possible to use such stabilization structure is highly invasive, since it is necessary to create enough space close to the vertebra to perform the various steps of assembly, with considerable difficulty for the surgeon, who has to arrange and assemble each individual element directly on the vertebra.

Moreover, the stabilizer described above does not allow a transverse connection between screws mounted on different vertebrae to transmit forces in a diagonal direction with respect to the axis of the spinal column.

Further, the tensioning cord must be threaded in the spacing body, and this requires a higher skill effort for the surgeon.

Known types of stabilizers do not allow creation of a stabilizer of the hybrid type that is totally modular, i.e., capable of adapting to all the configurations that the pathology of the patient may require and are decided on by the surgeon, for example rigid-dynamic-rigid, or dynamic-rigid-dynamic.

However, the known type of stabilizer device is unable to adapt to angle variations with which the pedicle screws might be fitted within the vertebrae, and therefore, if the positioning of such pedicle screws is not performed, in two adjacent vertebrae, with the same angle, the surgeon encounters difficulties in mounting the stabilizer device fitted over the heads of the pedicle screws.

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