US 12,336,743 B2
Polyaxial surgical screw and device for implanting said surgical screw
Francesco Siccardi, Castel San Pietro (CH); Meinrad Fiechter, Castel San Pietro (CH); Marco Riva, Castel San Pietro (CH); and Marco Rampon, Castel San Pietro (CH)
Assigned to Medacta International SA, Castel San Pietro (CH)
Appl. No. 17/602,224
Filed by MEDACTA INTERNATIONAL SA, Castel San Pietro (CH)
PCT Filed Apr. 6, 2020, PCT No. PCT/IB2020/053261
§ 371(c)(1), (2) Date Oct. 7, 2021,
PCT Pub. No. WO2020/208496, PCT Pub. Date Oct. 15, 2020.
Claims priority of application No. 102019000005358 (IT), filed on Apr. 8, 2019.
Prior Publication US 2022/0175426 A1, Jun. 9, 2022
Int. Cl. A61B 17/70 (2006.01); A61B 90/00 (2016.01)
CPC A61B 17/7085 (2013.01) [A61B 90/03 (2016.02); A61B 2090/037 (2016.02)] 10 Claims
OG exemplary drawing
 
1. A system comprising:
a polyaxial surgical screw, said polyaxial surgical screw having an internally hollow tulip having a first open end for accessing inside the tulip, a second end opposite to the first end, a side wall extending between the first and the second end, and at least two elongated rods projecting from the side wall and extending from the first end in a direction opposite to the second end, said polyaxial surgical screw having a threaded shank having a first end defining a tip of the polyaxial surgical screw and a second end opposite to the first end having a ball joint joined to the second end of the tulip to orient said shank with respect to the tulip itself, wherein said rods have respective concave inner faces facing each other, and a thread is formed on the concave inner faces of the rods near the tulip and on a cylindrical inner surface of the side wall; and
an implantation device comprising:
a shaped tip for engaging the second end of the threaded shank to rotate the shank itself about its own longitudinal extension axis;
a tubular body having a first end supporting the shaped tip and a second end opposite to the first end and configured to remain outside a patient's body, said tubular body also defining at least one housing cavity configured to engage an elongated rod of said at least two elongated rods of the polyaxial surgical screw; and
a rotation component of the shaped tip, extending along the tubular body and configured to be actuated by an operator;
wherein said tubular body comprises two housing cavities configured to engage said elongated rods of the polyaxial surgical screw, said cavities being spaced apart by two corresponding arched walls, each-arched wall having two longitudinal edges which can abut with longitudinal edges of the elongated rods, said arched walls defining, in cooperation with outer surfaces of the elongated rods, a continuous cylindrical surface with a circular cross-section,
wherein each arched wall comprises an end portion that defines the first end of the tubular body, said first end of the tubular body comprising a collar, wherein at least a portion of the collar is disposed radially inward from the arched walls, the collar defining a sliding hole configured to receive said shaped tip,
wherein said rotation component comprises an actuation cylinder extending through the tubular body and rotating inside the body itself, said cylinder being engaged at the tip to rotate the tip itself in an engagement configuration of the threaded shank,
wherein said rotation component further comprises a bush having an outer surface that is at least partially threaded, said bush being housed inside the tubular body and defining a longitudinal through cavity for housing said actuation cylinder, said threaded surface of the bush being configured to be screwed onto the thread formed on concave inner faces of the elongated rods and on the inner cylindrical surface of the polyaxial surgical screw, and
wherein said bush is attached to the actuation cylinder along a common longitudinal axis and is rotatable relative to the cylinder about said common longitudinal axis.