Patent ID: 7731734

Claim:
Vertebral osteosynthesis equipment, comprising: a polyaxial anchoring member ( 1 ) comprising i) a proximal threaded stud ( 5 ) and ii) a threaded base portion ( 6 ) enabling bony anchoring, the proximal stud articulated with respect to the base portion ( 6 ), the threaded base portion ( 6 ) comprising i) a threaded portion for bony anchoring, ii) a proximal curved wall ( 17 ) with a hemispherical proximal form defining a cavity ( 16 ), and iii) a collar ( 18 ) located between the curved wall ( 17 ) and the threaded portion at a location suitable for abutting against a pedicula, the proximal stud ( 5 ) comprising i) a threaded portion ( 10 ), and ii) a distal head ( 11 ), the distal head ( 11 ) retained in the cavity ( 16 ) by the curved wall ( 17 ); a connecting part ( 3 ) engaged on the threaded stud ( 5 ), the connecting part ( 3 ) comprising i) a rounded section ( 20 ) connected to ii) two parallel lateral wings ( 21 ) with holes for engaging on the proximal stud ( 5 ), iii) a circular wall ( 27 ) delineating an internal concave spherical face ( 28 ) mating with the curved wall ( 17 ) of the base portion ( 6 ), the circular wall ( 27 ) protruding perpendicularly from a lower surface of a lower one of the lateral wings ( 21 ), the rounded section for connecting a linking rod ( 2 ) to the anchoring member ( 1 ); and a clamping part ( 4 ) screwed on the threaded portion ( 10 ) of the proximal stud ( 5 ) and clamping against an upper one of the wings ( 21 ) of the connecting part ( 3 ), wherein, the circular wall ( 27 ) delineating the internal concave spherical face ( 28 ) bears against the curved wall ( 17 ) of the base portion ( 6 ), an amount of multidirectional backlash of the proximal stud ( 5 ) being limited by a lowermost surface of the circular wall ( 27 ) abutting against an upper surface of the collar ( 18 ), wherein, the proximal stud ( 5 ) further comprises a collar ( 12 ) forming an axial stop surface, and the connecting part ( 3 ) further comprises a circular cavity ( 26 ) shaped to engage with the collar ( 12 ) of the proximal stud ( 5 ), the circular cavity ( 26 ) is engaged with the collar ( 12 ) of the proximal stud ( 5 ), with a longitudinal axis of the stud ( 2 ) in alignment with a longitudinal axis of the base portion ( 6 ), the stud ( 2 ) is in a neutral first position with the lowermost surface of the circular wall ( 27 ) held spaced apart from the upper surface of the collar ( 18 ) of the base portion ( 6 ) at a distance defined by said circular cavity ( 26 ) engaged with said axial stop surface of the collar ( 12 ) of the stud ( 5 ), and with the clamping part ( 4 ) screwed on the threaded portion ( 10 ) of the proximal stud ( 5 ) clamping the upper one of the wings ( 21 ) against the lower one of the wings ( 21 ), the stud ( 2 ) is moveable from the first position to a second position with the lowermost surface of the circular wall ( 27 ) abutting against the upper surface of the collar ( 18 ) of the base portion ( 6 )