Vertebral osteosynthesis equipment

1. Vertebral osteosynthesis equipment, comprising:

at least one connecting bar having an assembly portion designed to extend along the vertebrae be treated, this assembly portion having a circular cross-section;

at least two anchoring members designed to be anchored in the vertebrae be treated, each anchoring member comprising an outwardly threaded proximal pin;

at least one connecting part of the so-called “side loading” type, i.e., comprising an engagement duct for the engagement of said assembly portion that is laterally offset relative to an assembly duct for the engagement of the connecting part on the proximal pin comprised by the associated anchoring member; said engagement duct has a circular cross-section with openings on two opposing sides, and said assembly portion is designed to be engaged through said engagement duct, the connecting part being capable to pivot around said assembly portion when the assembly portion is engaged in the engagement duct; and

tightening nuts designed to be screwed on said threaded proximal pins of the anchoring members, so as to mount said connecting part on said associated anchoring member;

said assembly portion comprises at least one protruding lug situated on the side of one of its ends, and

said connecting part has a longitudinal slot emerging in said engagement duct, sized to receive said lug in an adjusted manner, but with the lug being able to slide therein, said connecting part being able to be engaged on said assembly portion beyond that lug.

2. Equipment according to claim 1 , characterized in that:

said engagement duct is arranged on one side of the connecting part, so that, when the connecting part is engaged on said assembly portion, the connecting part adopts by gravity a first angular position on the assembly portion;

the lug and said slot are so positioned relative to, respectively, the connecting bar and the connecting part that the angular engagement position permitting to engage the connecting part on the lug is a second angular position distinct from said first angular position and angularly separated therefrom.

3. Equipment according to claim 2 , characterized in that said first and second position are angularly separated by at least 90 degrees, and more preferably by 180 degrees.

4. Equipment according to claim 1 , characterized in that:

said connecting part is U-shaped, i.e., comprises a base part and two parallel branches connected to that base part, which are separated from one another by an interstice, said engagement duct of the assembly portion being defined by that base part and by the base of those parallel branches; and

said longitudinal slot is formed by the portion of said interstice extending along the base of the parallel branches.

5. Equipment according to claim 1 , characterized in that the connecting bar has an eyelet at one end and an intermediate portion connecting that eyelet to said assembly portion, said intermediate portion being dimensioned to laterally offset the axis of the eyelet relative to the longitudinal direction of said assembly portion, by a distance substantially equal to the distance by which, on said connection portion, said engagement duct of the assembly portion is offset relative to said assembly duct.

6. Equipment according to claim 5 , characterized in that said intermediate portion is at an angle.

7. Equipment according to claim 5 , characterized in that said connecting bar comprises, at the connecting zone of said intermediate portion to said assembly portion, or near that zone, a bearing surface for an instrument making it possible to move said connecting part, engaged on said assembly portion.

8. Equipment according to claim 7 , characterized in that said bearing surface is in the form of a collar secured to the connecting bar.

9. Equipment according to claim 1 , characterized in that said assembly portion is dimensioned lengthwise so as to receive two anchoring members/connecting part assemblies; the equipment then comprises not only a first assembly formed by said connecting part and said anchoring member associated with the connecting part, but also a second assembly formed by a second connecting part and a second anchoring member associated with that second connecting part.

10. Equipment according to claim 9 , characterized in that:

said second connecting part is of the “open” type, i.e., forms a curved portion that defines said engagement duct of said assembly portion, said curved portion being able to surround the assembly portion only partially, and

said second assembly comprises a closing means making it possible to close this engagement duct when said second connecting part is gripped on said associated second anchoring member.

11. Equipment according to claim 10 , characterized in that said closing means may also be in the form of a locking part forming a passage through it, that passage allowing the engagement of that locking part on a threaded proximal pin comprised by said associated second anchoring member; said locking part then comprises:

a body forming said curved portion, and

said locking part, which comprises:

a locking portion designed to bear against said associated second anchoring member and forming a lateral closing extension of said engagement duct, and

an assembly portion dimensioned to be engaged in an assembly duct comprised by said body and to slide in said duct, that sliding occurring between a separated position of said body and said locking part, in which said lateral extension does not hinder the transverse engagement of said assembly portion in said engagement duct, and a close position of said body and said locking part, in which said lateral extension is at a distance from said curved portion such that it closes said engagement duct and it keeps said assembly portion in that duct.