1. A surgical instrument for fixing the vertebrae through the posterior or posterolateral access, consisting of: - a tubular member formed by two uprights (7, 8) separated by a longitudinal hollow area, the racks (7, 8) are connected at their distal end, - in each of said uprights (7, 8) on the inner surface has a guide groove with a section of a dovetail, - an insert (9) with two diametrically positioned longitudinal sliding surfaces having a cross section in the form of a dovetail corresponding to the cross section are indicated x guiding grooves, wherein the proximal end of each of the uprights (7, 8) has a projection (15) as a fixing device, which may include a receiving unit (20, 21) by transverse displacement of said stoek.2. A surgical instrument for fixing vertebrae with posterior or posterolateral access by n. 1, characterized in that at the proximal end of each of the uprights (7, 8) has a transverse projection (15, 15 ), which can enter the recess (20, 21) on the screw head under the action of elastic deformation of the lateral uprights (7, 8) .3. A surgical instrument according to any one of claims. 1 or 2, characterized in that said protrusion (15) has a substantially conical proximal surface (17) forming the insertion channel opens in the distal direction, wherein the channel in the closed position is complementary to the shape of the outer surface of the head vinta.4. A surgical instrument according to any one of claims. 1 or 2, characterized in that at rest said racks (7, 8) diverge in a proximal chasti.5. A surgical instrument according to any one of claims. 1 or 2, characterized in that the racks (7, 8) can be moved between a position in which the proximal ends extend from each drugog1. Хирургический инструмент для фиксации позвонков через задний или заднебоковой доступ, состоящий из:- трубчатого элемента, образованного двумя стойками (7, 8), разделенными продольной пустотелой зоной, при этом стойки (7, 8) соединены на их дистальном конце,- в каждо
