Artificial spinal disc and artificial disc insertion method using the same

Abstract

An artificial spinal disc including an upper disc formed in a plate shape with top coupled to an upper vertebra, a protruding joint portion protruding from a lower surface of the upper disc, and a lower disc formed in a plate shape with bottom coupled to a lower vertebra wherein the protruding joint portion is seated on an upper surface of the lower disc. According to the foregoing description, the artificial disc is implanted through the lateral or anterolateral approach to the spine, rather than the anterior approach, and such lateral implantation is straightforward.

1 . An artificial spinal disc inserted between an upper vertebra and a lower vertebra, the artificial spinal disc comprising:
 an upper disc formed in a plate shape, with top coupled to the upper vertebra;   a protruding joint portion including a main joint portion protruding from a lower surface of the upper disc, and one or multiple auxiliary joint portions spaced apart from a side of the main joint portion and protruding from the lower surface of the upper disc; and   a lower disc formed in a plate shape, with bottom coupled to the lower vertebra, the lower disc having, on an upper surface, a main joint groove in which the main joint portion is seated and an auxiliary joint groove in which the auxiliary joint portion is seated to allow the protruding joint portion to make multidirectional movements.   
     
     
         2 . The artificial spinal disc according to  claim 1 , wherein the auxiliary joint portion includes:
 a first auxiliary joint portion disposed at a distance on one horizontal side of the main joint portion, and   a second auxiliary joint portion disposed at a distance on the other horizontal side of the main joint portion.   
     
     
         3 . The artificial spinal disc according to  claim 2 , wherein the first auxiliary joint portion and the second auxiliary joint portion are symmetrically disposed with respect to the main joint portion on a plane. 
     
     
         4 . The artificial spinal disc according to  claim 2 , wherein each of the first auxiliary joint portion and the second auxiliary joint portion is formed in a hemispherical shape. 
     
     
         5 . The artificial spinal disc according to  claim 2 , wherein each of the first auxiliary joint portion and the second auxiliary joint portion is formed in a semi-ellipsoidal shape. 
     
     
         6 . The artificial spinal disc according to  claim 5 , wherein each of the first auxiliary joint portion and the second auxiliary joint portion is formed such that a long axis connecting two points on a plane is disposed along a front-rear direction of a spine. 
     
     
         7 . The artificial spinal disc according to  claim 2 , wherein the main joint portion is formed in a hemispherical shape. 
     
     
         8 . The artificial spinal disc according to  claim 2 , wherein the main joint portion is formed in a semi-ellipsoidal shape. 
     
     
         9 . The artificial spinal disc according to  claim 8 , wherein the main joint portion is formed such that a long axis connecting two points on a plane is disposed along a left-right direction of a spine. 
     
     
         10 . The artificial spinal disc according to  claim 2 , wherein the main joint portion protrudes higher than a protrusion height of the auxiliary joint portion. 
     
     
         11 . The artificial spinal disc according to  claim 1 , wherein the protruding joint portion is integrally formed with the upper disc. 
     
     
         12 . The artificial spinal disc according to  claim 1 , wherein the upper disc and the lower disc are spaced apart from each other at a distance between the lower surface of the upper disc and the upper surface of the lower disc in a range of 3 mm to 6 mm when the protruding joint portion is seated. 
     
     
         13 . The artificial spinal disc according to  claim 2 , wherein the first auxiliary joint portion and the second auxiliary joint portion are formed with a smaller planar area than a planar area of the main joint portion. 
     
     
         14 . The artificial spinal disc according to  claim 13 , wherein the auxiliary joint portion is formed such that a center of each of the first auxiliary joint portion and the second auxiliary joint portion is disposed at an anterior portion of a spine with respect to a center of the main joint portion. 
     
     
         15 . The artificial spinal disc according to  claim 13 , wherein the first auxiliary joint portion and the second auxiliary joint portion are configured to have a same shape and planar area. 
     
     
         16 . The artificial spinal disc according to  claim 2 , wherein the upper disc and the lower disc include a first side formed along one anterior side of the main joint portion and one anterior side of the first auxiliary joint portion, a second side having one side connected to one side of the first side and formed along the other anterior side of the main joint portion and one anterior side of the second auxiliary joint portion to form a set angle with the first side, and a third side having one side connected to the other side of the first side and the other side connected to the other side of the second side and formed along one posterior side of the first auxiliary joint portion and one posterior side of the second auxiliary joint portion. 
     
     
         17 . The artificial spinal disc according to  claim 16 , wherein the upper disc and the lower disc have a plane shape of an approximate triangular shape formed by the first side, the second side and the third side. 
     
     
         18 . The artificial spinal disc according to  claim 17 , wherein each of the upper disc and the lower disc is arranged with the third side facing an anterior side of a spine. 
     
     
         19 . The artificial spinal disc according to  claim 17 , wherein each of the upper disc and the lower disc is configured to have one or multiple concave portions on the third side. 
     
     
         20 . The artificial spinal disc according to  claim 2 , wherein the upper disc and the lower disc include:
 a first curved side formed along an anterior side of each of the first auxiliary joint portion, the main joint portion and the second auxiliary joint portion, and curved on a plane, and   a second curved side connected to the first curved side, formed along a posterior side of each of the first auxiliary joint portion, the main joint portion and the second auxiliary joint portion and curved on the plane.   
     
     
         21 . An artificial disc insertion method, comprising:
 inserting an artificial disc into an implantation space between an upper vertebra and a lower vertebra of a human body, the artificial disc including an upper disc formed in a plate shape, with top coupled to the upper vertebra, a protruding joint portion including a main joint portion protruding from a lower surface of the upper disc, and one or multiple auxiliary joint portions spaced apart from a side of the main joint portion and protruding the lower surface of the upper disc, and a lower disc formed in a plate shape, with bottom coupled to the lower vertebra, the lower disc having, on an upper surface, a main joint groove in which the main joint portion is seated and an auxiliary joint groove in which the auxiliary joint portion is seated to allow the protruding joint portion to make multidirectional movements, wherein the artificial disc is inserted through a lateral or anterolateral approach to a spine and the auxiliary joint portion is first inserted into the implantation space;   pushing the artificial disc into the implantation space such that the main joint portion is disposed at a center of the upper vertebra and the lower vertebra on a plane; and   adjusting a location of the artificial disc.