WO2010130060A1 - Intervertebral disk pillow - Google Patents

Abstract

The intervertebral disk pillow (25) according to the invention is placed inside the annulus fibrosus (20) in the place of the nucleus pulposus by introducing said pillow in the folded state of the casing (25) thereof through an opening in the annulus fibrosus (20) into the interior thereof and there filling the pillow until the vertebrae have reached their natural spacing again, and in particular until the facet joints have been relieved.

Description

 Disc pads

The present invention relates to a disc pad according to claim 1 and a method according to claim 9.

This disc cushion or the method according to the invention find their use for the therapy of the spine, in particular of the human spine.

The intervertebral disc is located between adjacent vertebrae of the spine, which is stabilized by ligaments and musculature, and allows their movement carried over the facet joints, since the vertebrae themselves are stiff. In addition, the transmission of forces from one vertebra to the other vertebra essentially takes place through the intervertebral disk, with the result that this not only has to be deformable, but at the same time must also be able to withstand high levels of stress. In addition, the intervertebral disc also has a damping effect against impact occurring stress.

Excessive deformation, stress or even aging lead to the known frequently occurring functional damage to the intervertebral disc, which in addition to pain, a disability to immobility result. By way of example, it should be mentioned that with a reduced thickness of the intervertebral disc, whether by herniated disc, by aging or by another reason, an altered relative position of the separated vortices results, with the result that then the facet joints are loaded incorrectly, which in turn leads to joint damage and pain.

The intervertebral disc itself consists of two components: the nucleus pulposus, whose gelatinous mass ensures the mechanical function of the intervertebral disc, and then the annulus fibrosus, which laterally encloses the nucleus pulposus held above and below via the end plates of the vertebral bodies caught his position and exposed to the action of the spine essentially hydrostatic pressure Is.

Intervertebral disc damage occurs, among other things, if by cracking in the annulus fibrosus mass of the nucleus pulposus emerges (band disc prolapse) or if the loss of water with degradation of the proteoglycans, the diet of the nucleus pulposus is given only deficient and this shrinks, so that the height of the intervertebral disc is reduced.

As mentioned above, then have the vertebral bodies only insufficient distance from each other, whereby the fixation of the vertebral bodies on the surrounding muscles and ligaments becomes loose, so that they can move on the one hand laterally against each other and on the other hand, the facet joints are wrongly loaded. As a result, the functionality of the spine is painfully reduced.

Numerous other pathological manifestations of the intervertebral disc are known.

For therapy, it has been attempted to replace the natural disc by an artificial disc in which it is inserted through the abdominal cavity and inserted between the affected vertebrae. Such a procedure through the abdominal cavity is risky; In addition, various problems arise in the field of artificial disc. in the

Result must be determined that this technique is still at the beginning and is problematic.

Accordingly, it is the object of the present invention to provide an apparatus and method for improved therapy of disc damage.

Because according to the invention a disc cushion is provided which can be placed through an opening in the annulus fibrosus, the annulus fibrosus can be left in its natural position and mass of the nucleus pulposus can be artificially replaced, resulting in a minimal Lasting therapy for defective discs leads.

The invention will be described below with reference to the figures.

It shows:

1 shows two adjacent vertebrae of a spinal column,

2a shows a cross section through an intervertebral disc with a view of the vortex located above this,

2b shows the view of Fig. 2a, wherein according to the invention a disc pad is inserted into the annulus fibrosis, and

Fig. 3 is a view of an inventive disc cartridge.

Fig. 1 shows two adjacent, supported by an intervertebral disk 1 to each other vertebrae 2 and 3, wherein further intervertebral discs 4 and 5, but to relieve the figure in turn to this subsequent further Wir- are no longer shown in. The shape of the vertebrae varies over the various sections of the spine (i.e., from the lumbar to cervical spine); however, the inventive disc pad is basically not bound to any particular form of the vertebra, except for the cervical vertebrae C1 and C2. The vertebrae shown in FIG. 1 (and also in the further figures) therefore do not limit the use of the disc cushion to a specific section of the spinal column.

The vertebral bodies 6 and 7 with the associated spinous processes 8 and 9, the transverse processes 10 and 11 and the upper joint extensions 12 and 13 and the lower articular processes 14 and 15 can be seen.

The end of the lower articular process 14 of the (upper) vertebra 2, together with the end of the upper articular process 13 of the (lower) vortex 3, forms the facet joint 16, in which the ends of the gels are protected. ze 13,14 can slide on each other and sσ-the funkfeionsgefee - allow guided deflection of the spine. As a result, a vertebra is operatively guided and supported by the sliding surfaces of the facet joints 16, the intervertebral disc, the surrounding ligaments and musculature. If the intervertebral disc loses its natural thickness, this composite is disturbed and the facet joints 16 are loaded incorrectly, which often leads to overuse with, for example, painful inflammation, etc.

FIG. 2 a shows a section through the intervertebral disk 1 along the line AA of FIG. 1 with a view of the vertebral body 6 of the vertebra 2.

The intervertebral disc 1 consists of the annulus fibrosus 20, which encloses the gelatinous nucleus Pulposus 21 and in the healthy state prevents under pressure load of the vertebrae 2, 3 (Figure 1) the gelatinous mass of the annulus fibrosus 20 between the vertebrae 2,3 laterally out is squeezed. The nucleus pulposus has a water content of about 70 to 80 percent and loses by the daily load continuously a little fluid, so that the disc slump something. During bedtime at night, the lost fluid is resumed by osmotic pressure, so that the disc recovers its thickness (and in the morning the spine is a few inches longer than the evening before).

This alternating fluid flow allows the transport of nutrients into the nucleus pulposus, but may degenerate in old age, causing the nucleus pulposus to subsequently shrink, which in addition to the otherwise causal mechanical overuse of an intervertebral disc with age-related reduced thickness and the concomitant above mentioned dysfunctions and discomfort leads.

Furthermore, the vertebral arch 23 and the projections 8 and 10 described in FIG. 1 as well as the lower articular appendage 14 with its joint socket 24 are visible in FIG. 2a. The upper articular processes 12 (Figure 1) are hidden in the present view. FIG. 2b shows the section of FIG. 2a, with the nucleus pulposus being replaced by a disc cushion 25 according to the invention, which fills the space in the annulus fibrosus 20 and replaces the nucleus pulposus.

The biovertäglich shell 26 of the disc cushion 25 is substantially inextensible, but flexible and filled with a fluid, preferably a liquid filled with high viscosity, so that the mechanical properties of the disc cushion 25 as far as possible (or as indicated in the specific case ) approximate those of the nucleus pulposus. A filling with an isotonic saline solution, with or without gases (eg oxygen), or a water / oil emulsion, or a water / gel solution (colloid), or water / collagen solution can, as mentioned, tuned by the skilled person the specific case.

A valve 28 protrudes through an opening 27 in the annulus fibrosus 20 and allows the filling of the intervertebral disc cushion placed inside it with the abovementioned fluids, wherein the valve 28 is designed so that it can be permanently closed after filling, so that Under operating pressure no leakage of the fluid takes place. Alternatively, the valve 28 may be configured for refilling, e.g. to compensate for minor leaks over time or to allow replacement of the fluid when other properties such as e.g. a different viscosity promise improved therapeutic success.

As a result, a return of the distance of the vertebrae 2,3 to the normal intervertebral disc height is achieved by the intervertebral disc cushion 25 according to the invention without the need to change the remaining anatomy. This applies, apart from the opening 27 to be created, in particular also for the annulus fibrosus 20. This increase in height relieves the facet joints 16 (FIG. 1) and reduces the pain generators in these joints. The original mobility can be achieved again, which is compatible with the previous techniques such as a rigid bensatzplastik or stiffening of the vertebrae 2,3 is not the case.

FIG. 3a shows a schematic view of a disc cushion 30 of a preferred embodiment. The intervertebral pad 30 is filled with a non-compressible fluid, e.g. an isotonic saline solution and presented with an outline, which it occupies when it is inserted in a ring Fibrosus 20 (Figure 2b). The sheath 32 is substantially non-stretchable.

FIG. 3b shows a likewise schematized view of a disc cushion 35 with a reinforced, circumferentially extending edge region 36, which is intended to rest against the inner wall of the annulus fibrosus. By means of such an edge region 36, the annulus fibrosus 20 is relieved of tensile stress due to the internal pressure of the implanted disc cushions 30, which may be expedient in particular with regard to a rupture or a cut for the insertion of the disc cushion. Next, the envelope 32 is flexible and designed for a bursting pressure of at least 30 bar, which corresponds to the physiological maximum occurring in the nucleus pulposus operating pressure.

Alternatively, the sheath of another, not shown embodiment can be easily stretched, so that they can create properly on bumps in the inner wall of the annulus fibrosis or the cover plates of the vertebrae.

In another embodiment, the sheath is reinforced by a mesh structure that can absorb the operating internal pressure of the disc cushion. Such a network structure is formed as a non-resorbable plastic fiber network, which in turn envelops the shell. The mesh structure may be connected to or integrated into the shell, but may also simply be pulled over the shell so that it covers it.

In a further embodiment, the envelope is designed with elements detectable for non-contact diagnostic devices, in particular with X-ray strips are provided, which allow during the implantation (and later) to track the position of the disc cushion and to verify its intended position.

In another embodiment, the sheath of the disc cushion is made of a fabric of polyester fiber, and may be an inner and / or outer gum, e.g. made of neoprene or PVC.

Furthermore, it is particularly preferable for the sheath of the disc cushion to have a multilayer structure, one of the layers being formed in a fluid-tight manner, preferably for water and / or gas. Then, one of the other layers can be formed tensile strength, such that this layer can absorb the stress generated by the operating internal pressure of the disc cushion in the shell. Another outermost layer may be configured to resist mechanical damage and thus mechanically injure the sheath during implantation or when applied to a non-smoothed site, e.g. to prevent the cover plates.

FIG. 4 shows the disc cushion 30 of FIG. 3 in a folded state, with longitudinal folds 35, such that it is inserted through an opening 27

(Figure 1) in the annulus Fibrosus 20 can be passed and placed in its interior. The opening 27 can be easily created in the annulus Fibrosus 20 by a suitable incision, which can be sized by the skilled person according to size and location according to the specific circumstances. Once the disc cushion 30 completely in the room in

Annulus Fibrosus 20 is introduced, it can be filled via the valve 28 as intended.

In other words, in addition to the disc pillow according to the invention, a method according to the invention is also available, according to which a disc pad is inserted through an opening of the annulus fibrosus in its natural position and then filled in the latter until the vertebrae adjoining the annulus fibrosus necessarily have a minimal pathological distance. Preferably, the method is used such that the naturally located annulus fibrosus first opens and at least a portion of the mass of the nucleus pulposus is removed through this opening, then inserted a disc pad through this opening in the space bounded by the annulus fibrosis and finally the Disc cushion is filled until it occupies a predetermined volume, which essentially corresponds to the healthy, replaced by the disc cushion nucleus pulposus.

Claims

claims 1 disc cushion, which may be placed within the annulus fibrosus in place of mass of the nucleus pulposus, with a flexible, fillable via a valve sheath, which consists of biocompatible material and in the unfilled state is deformable so that they pass through an opening in the annulus Fibrosus can be guided into this, and with a valve disposed on the side of the valve, which allows the filling of the placed within the annulus fibrosis disc cushion and which permanently withstands the operating pressure. 2. disc pad according to claim 1, wherein the shell withstands a bursting pressure of at least 30 bar. 3. disc pad according to claim 1 or 2, wherein the shell has a network structure, which is preferably designed as a plastic net covering this. 4. Disc cushion according to one of claims 1 to 3, wherein this or the network structure is provided with detectable for non-contact diagnostic equipment elements, preferably X-ray strips. 5. Disc cushion according to one of claims 1 to 4, wherein the shell is constructed of a plurality of layers and one of the layers fluid-tight, preferably for water and / or gas is formed. A disc pad according to claim 5, wherein one of the layers is adapted to receive the stress generated in operation by the internal pressure of the pad in the sleeve. A disc cartridge according to any one of claims 5 to 6, wherein one of the layers resists mechanical damage. 8. A method for the therapy of disc damage, characterized in that a disc cushion is inserted through an opening of the naturally located annulus fibrosus into its interior space and filled therein, until the vertebral bodies adjacent to the annulus fibrosus necessarily have a minimal pathological distance. 9. A method according to claim 8, characterized in that the naturally located annulus fibrosus is opened and at least part of the mass of the nucleus pulposus is removed through this opening, then a disc cushion is introduced through this opening into the space bounded by the annulus fibrosus and Finally, the disc pad is filled until it occupies a predetermined volume, which essentially corresponds to the healthy, replaced by the disc cushion nucleus pulposus. 10. The method of claim 9, wherein the disc pad has the features of any one of claims 1 to 8.