Displacement device, use and system therefore
Embodiments of the present disclosure are directed to a systems, devices and methods for displacing bones of a living mammal. In some embodiments, a device is provided which includes at least two engagement elements positioned at a distance from each other for engagement with two separate bones Each of the engagement elements may be carried by a support part which in turn is supported in a support portion of a distance unit ( 5 ). The said support part and support portion form a support unit, where each engagement element extends at an angle (α) with respect to a straight line (L) between two support units. At least one of the support units includes an arrangement for altering the angle which includes an actuating unit maneuverable for adjustment of the angle (α). Some embodiments of the disclosure are directed to a system for engagement with vertebrae including such devices (noted above), as well as uses of the device and associated methods of treatment.
1. A bone displacement device for displacing bones relative to one another in a living mammal, the device comprising:
first and second support units each comprising a support portion and a support part, the support part having external threads and being supported by the support portion, wherein the first support part of the first support unit includes a pin in pivotal cooperation with a bearing provided in the second support part,
a distance unit having controlled displacement means for controlling displacement between the support units with respect to one another to alter the degree of separation of the bones;
at least two elongated engagement elements spaced apart from one another for engagement with at least two separate bones, the engagement elements comprising at least a first engagement element and a second engagement element each having a substantially longitudinal axis, wherein
each engagement element is housed by a respective support part, and
each engagement element extends at a respective angle with respect to a straight line between the support units,
and
angle-altering means provided with at least one of the support units configured to accurately alter the angle between the engagement elements and thus, the associated bones, the angle-altering means comprising an actuating unit maneuverable to adjust the angle via the respective support part, wherein the actuating unit includes
a setting element comprising a cam arranged on the first support part and configured to act against a surface portion on the second support part, and
a sleeve having an end surface and internal threads for engagement with the external threads of the support part, wherein
the sleeve is configured to axially displace upon rotation along the support part and thereby correspondingly along the engagement element,
the end surface of the sleeve is directed axially and cooperates with the cam, and
the angle-altering means operates in at least two modes: an adjustment mode where the angle between engagement elements can be altered, and a locked mode where the angle between engagement elements is locked in position, the locked mode occurring upon interaction of the end surface of the sleeve with the cam of the at least one support unit.
2. The device according to claim 1 , wherein the engagement elements have screw treads for engagement with bones.
3. The device according to claim 1 , wherein the distance unit is telescopic and capable of being extended such that the support portions and thereby the support parts and thus the engagement elements are displaced in respect of each other.
4. The device according to claim 1 , wherein the support portions of one distance unit are rotational relative to each other around a symmetry axis for a piston-cylinder aggregate being included in the distance unit.
5. The device according to claim 1 , wherein the distance unit further comprises a piston-cylinder aggregate having a symmetry axis, and wherein the support portions of the distance units are rotational relative to each other around the symmetry axis.
6. The device according to claim 1 , wherein the device is configured to displace vertebrae in a spinal column.
7. A system for engagement with vertebrae in a spinal column comprising at least one device according to claim 1 , and a holder for a prosthesis, the holder selected from the group consisting of: a disc implant, a vertebral implant, wherein the holder is configured to be adjustably fixable to the at least one device.
8. The system according to claim 7 , wherein the holder includes a fork-shaped head for external or internal co-operation with the implant.
9. The system according to claim 1 , further comprising at least one deflector which is fixed on the at least one device, the deflector configured for holding an operation point for engagement with vertebrae free from body organs.
10. The system according to claim 1 , wherein the system further comprises positioning means for an implant having at least one positioning arm with a first portion for engagement with the displacement device and a second portion for engagement with a holder for an implant, and wherein the holder is fastenable in a desired position.
11. The system according to claim 1 , wherein the system further comprises a tool for manipulating the actuating unit.
12. The system according to claim 1 , wherein the system further comprises manipulation means for manipulating the engagement elements.