| CPC A61F 2/44 (2013.01) [A61B 17/7002 (2013.01); A61B 17/7035 (2013.01); A61B 17/7076 (2013.01); A61B 2017/8655 (2013.01)] | 17 Claims |
|
1. A spinal implant having a detachable head module, the spinal implant comprising:
an anchor including a body having a screw thread formed on an outer peripheral surface thereof, a hollow hole penetrated through the body in an axial direction, and a spherical body positioned at an upper end of the body and having a fixing groove, the anchor being configured to be percutaneously inserted into a vertebral body through skin;
a housing including an accommodation portion opened in a transverse direction and having a screw thread formed on an inner peripheral surface thereof, a plurality of U-shaped grooves formed in a bottom surface of the accommodation portion, and a seating hole penetrated through a lower center of the housing;
an inner lock including a cylindrical body tapered to fit into the seating hole of the housing, a concave surface formed in a central region of an outer peripheral surface of the cylindrical body and having a reduced thickness than a thickness of the cylindrical body to provide an elastic force, a cut-out groove formed at a predetermined angle in the cylindrical body, a bridge plate located at a lower end of the cut-out groove, the bridge plate having a thickness reduced relative to that of the cylindrical body, and being configured to withstand a predetermined torque during assembly of a head module, and to fracture when torque equal to or greater than the predetermined torque is applied to a set screw during secondary assembly to the spherical body of the anchor; and a rim formed on a lower end surface of the cylindrical body such that the rim is concave inward;
a rod including a pair of straight parts seated in the U-shaped grooves of the housing, and a coil part wound at a particular angle relative to a centerline that is eccentrically spaced apart from a centerline of the straight part by a predetermined distance, being seated in the U-shaped groove of the housing in an orientation in which a direction and gradient thereof are adjustable; and
a set screw configured to secure the rod by being fastened into the accommodation portion of the housing,
wherein the head module is configured by assembling the set screw in a state in which the inner lock is seated in the seating hole of the housing and the rod is seated to the U-shaped grooves of the housing.
|