Integrated expandable interbody spacer (IEIS)

A method of assembling an expandable interbody spacer for use in lumbar interbody fusion, comprising:

• installing a motion assembly between opposing isosceles-trapezoidal-shaped sidewalls of a first endplate and opposing isosceles-trapezoidal-shaped sidewalls of a second endplate by sliding a protrusion located on each isosceles-trapezoidal-shaped sidewall into a slanted motion guiding groove cut into a rounded profile of a first motion guider and into a slanted motion guiding groove cut into a rounded profile of a second motion guider;
• inserting a central tab extension located on each of the opposing isosceles-trapezoidal-shaped sidewalls of the second endplate into a respective central slot located in an opposing isosceles-trapezoidal-shaped sidewall of the first endplate;
• inserting a threaded screw through a smooth central cylindrical aperture of the first motion guider into a threaded central cylindrical aperture of the second motion guider;
• adjusting a height between an outwardly facing surface of the first endplate and an outwardly facing surface of the second endplate by inserting a surgical screwdriver into a screwhead of the threaded screw and rotating the screwdriver;
• and
• expanding a height between the first endplate and the second endplate by inserting the surgical screwdriver between a pair of bullet shaped endcaps into the screwhead and rotating the screwhead in a clockwise direction to draw the first motion guider and the second motion guider together by sliding along the slanted motion guiding grooves.

An expandable interbody spacer system, comprising:

• a first endplate including an outwardly facing surface, an inner facing surface and two opposing isosceles-trapezoidal-shaped sidewalls each configured with a central slot;
• a second endplate including an outwardly facing surface and an inner facing surface and two opposing isosceles-trapezoidal-shaped sidewalls each configured with a central tab extension, wherein the second endplate is positioned directly opposite the first endplate, wherein each central tab of the second endplate is configured to slide into a respective central slot of the first endplate;
• a motion assembly located between the opposing sidewalls of the first endplate and the opposing sidewalls of the second endplate, the motion assembly including:
• a first motion guider having a smooth central cylindrical aperture;
• a second motion guider having a threaded central cylindrical aperture;
• a surgical screwdriver;
• and
• a screw having a screwhead and a partially threaded shank, wherein the partially threaded shank is positioned through the smooth central cylindrical aperture of the first motion guider and into the threaded central cylindrical aperture of the second motion guider,
• wherein clockwise rotation of the screwhead by the surgical screwdriver is configured to increase a height between the first endplate and the second endplate by drawing the first motion guider and the second motion guider together,
• wherein counterclockwise rotation of the screwhead by the surgical screwdriver is configured to decrease a height between the first endplate and the second endplate by moving the first and second motion guiders apart,
• wherein the first motion guider further comprises:
• a rectangular cuboid body having a top face configured to contact the inner facing surface of the first endplate;
• a bottom face configured to contact the inner facing surface of the second endplate;
• a first wall which includes the smooth central cylindrical aperture, wherein the first wall faces towards a first wall of the second motion guider;
• a second wall opposite the first wall;
• a pair of bullet shaped endcaps attached to the second wall, wherein the pair of bullet shaped endcaps extends outwardly from the motion assembly;
• a third wall having a rounded profile;
• a fourth wall having a rounded profile opposite the third wall, wherein the third wall and the fourth wall are located between the top face and the bottom face;
• a pair of slanted motion guiding grooves cut into each of the rounded profile of the third wall and the rounded profile of the fourth wall, wherein a first slanted motion guiding groove is configured to slant from a central width axis of the first wall towards the top face near the second wall, and a second motion guiding groove is configured to slant from a central width axis of the first wall towards the bottom face near the second wall,
• wherein a respective protrusion of a sidewall of the first endplate is configured to slide within the first slanted motion guiding groove and a respective protrusion of a sidewall of the second endplate is configured to slide within the second slanted motion guiding groove of the first motion guider;
• the second motion guider further comprises:
• a rectangular cuboid body having a top face configured to contact the inner facing surface of the first endplate;
• a bottom face configured to contact the inner facing surface of the second endplate;
• a first wall configured to face towards a first wall of the first motion guider;
• a second wall opposite the first wall, wherein the threaded central cylindrical aperture is located within the rectangular cuboid body between the first wall and the second wall;
• a rounded endcap attached to either side of the second wall, wherein the rounded endcap extends outwardly from the motion assembly;
• a third wall having a rounded profile;
• a fourth wall having a rounded profile opposite the third wall, wherein the third wall and the fourth wall are located between the top face and the bottom face;
• and
• a pair of slanted motion guiding grooves cut into each of the rounded profile of the third wall and the rounded profile of the fourth wall, wherein a first slanted motion guiding groove is configured to slant from a central width axis of the first wall towards the top face near the second wall, and a second motion guiding groove is configured to slant from a central width axis of the first wall towards the bottom face near the second wall,
• wherein a respective protrusion of a sidewall of the first endplate is configured to slide within the first slanted motion guiding groove and a respective protrusion of a sidewall of the second endplate is configured to slide within the second slanted motion guiding groove of the second motion guider.