Vertebral osteosynthesis device

A vertebral osteosynthesis device for affixation to vertebrae, comprising:

• two rigid support rods adapted to be disposed substantially parallel, one on each side of spineous processes of the vertebrae;
• a plurality of bone anchoring elements, each bone anchoring element having one of a hook element adapted to fit around a vertebral process and a screw element adapted to be screwed into a vertebral pedicle and each bone anchoring element having two lateral walls extending in a direction opposite said hook and screw elements, said lateral walls being substantially parallel and flexible and having inside and outside faces, and upper and lower ends, said outside faces being inclined toward each other at the upper ends, said lateral walls delimiting between them a channel matching a transverse dimension of said support rods, the distance separating said lateral walls at the upper ends thereof being slightly less than the transverse dimension of said support rods whereby said bone anchoring elements may be provisionally attached to said support rods by clipping said bone anchoring elements to said support rods;
• a plurality of gripping elements, each gripping element being associated with a bone anchoring element and having two opposed side arms, the side arms having inside faces and outside faces, the inside faces being inclined at a slope matching the outside faces of said lateral walls and adapted to engage the outside faces of said lateral walls and to bring said lateral walls closer together during engagement of said lateral walls;
• and
• a plurality of gripping means for attaching said gripping elements to said bone anchoring elements, each of said gripping means passing through a side arm of a gripping element and threadably engaging a bone anchoring element and displacing said gripping element whereby the inside faces of said gripping elements engage and slide on said outside faces of said lateral walls of said bone anchoring elements to bring said lateral walls closer together.