| abstract |
In order to improve the placement of pedicle screws in the vertebrae of a patient's spine, this surgical treatment system (1) comprises a drill bit (10) that extends along a proximo-distal drill bit axis (X10) and that is suitable for drilling a hole in the pedicle of a vertebra when the drill bit is rotated. The drill bit includes, successively along the drill bit axis, a distal end (11), a cylindrical drill (12), centred on the drill bit axis and designed to drill the hole by cutting into and removing bone material from the pedicle of the vertebra so as to give a distal end portion of the hole a cylindrical shape, and a milling cutter (13) designed to cut bone material from the pedicle of the vertebra so as to give a proximal end portion of the hole a funnel shape gradually widening from the distal end portion of the hole. The system also comprises a pedicle screw (20) that extends along a proximo-distal screw axis (X20) and that is designed so as to be screwed into the hole by being rotated, after the drill bit has drilled the hole and has been removed from this hole. The pedicle screw includes a threaded rod (21) with a cylindrical shape centred on the screw axis and the nominal diameter of which (D21) is greater than the diameter (D12) of the drill. |