| 摘要 |
<p>An intervertebral support device to impose an anatomic distance between two adjacent vertebral bodies (11a, 11b), comprising a couple of vertebral support elements for introduction between the edge portions of the rear half of the vertebrae, at respective substantially symmetrical positions of the instantaneous rotation axis of the natural relative flexion-extension movement of the two adjacent vertebrae. The device assists stabilizing and/or restoring the correct position of the rotation axis, which characterizes the first stage of the degenerative breakdown, without significantly limiting the relative movement of the two vertebrae. The support elements have preferably a constraint means that constrains them to the edge portions of the vertebral bodies, in particular to resist the reaction force on the intervertebral disc. For instance, this constraint means consists of protruding parts (37) that protrude with respect to the support surfaces (32), for engaging with the inner surfaces (51 a, 51b) and/or the external surfaces (52a, 52b) of the edge portions of the adjacent vertebral bodies (13a, 13b); a spike for temporary or definitively fastening to the external surfaces (52a, 52b), which engage the holes (50); percutaneously retractable fastening transversal elements, which engage in use with the fibres of the annulus fibrosus (17); an osteoinductive means arranged on the support surface (32). The relative position of the support surfaces (32) can change into a plurality of use conditions, by a relative mobility means comprising such a central preferably cylindrical or frusto- conical bearing member (39) and made of a soft resilient material such as silicone or a shape-memory material or in alternative, but not exclusively, a convex element and a concave element that allow the relative rotation of two longitudinal portions 31 of the device with respect to each other. In an exemplary embodiment, the device is configured to be implanted through a monolateral access.</p> |
