An articulation assembly for a surgical instrument, comprising: a lead screw sub-assembly including first, second, third, and fourth lead screws, the first and third lead screws diagonally-opposite one another and the second and fourth lead screws diagonally-opposite one another; a first gear sub-assembly including a first housing (232, 234) at least partially capturing first and second gears therein, the first and second gears coupled to the first and third lead screws; a second gear sub-assembly configured to engage the first gear sub-assembly, the second gear sub-assembly including a second housing (252, 254) at least partially capturing third and fourth gears, a first central compound gear, and a first coupling gear disposed about a first input, the third and fourth gears coupled to the second and fourth lead screws, respectively, the first central compound gear including a distal gear and a proximal gear, the distal gear coupling the first and second gears with one another, thereby coupling the first and third lead screws with one another, the first coupling gear coupled with the proximal gear, the first input extending proximally from the second housing; and a third gear sub-assembly configured to engage the second gear sub-assembly, the third gear sub-assembly including a third housing (272, 274) at least partially capturing a second central compound gear and a second coupling gear disposed about a second input, the second central compound gear including a distal gear and a proximal gear, the distal gear coupling the third and fourth gears with one another, thereby coupling the second and fourth lead screws with one another, the second coupling gear coupled with the proximal gear, the second input extending proximally from the third housing, wherein the first input extends proximally through and from the third housing; wherein a rotational input provided to the first input rotates the first and third lead screws, and wherein a rotational input provided to the second input rotates the second and fourth lead screws. a lead screw sub-assembly including first, second, third, and fourth lead screws, the first and third lead screws diagonally-opposite one another and the second and fourth lead screws diagonally-opposite one another; a first gear sub-assembly including a first housing (232, 234) at least partially capturing first and second gears therein, the first and second gears coupled to the first and third lead screws; a second gear sub-assembly configured to engage the first gear sub-assembly, the second gear sub-assembly including a second housing (252, 254) at least partially capturing third and fourth gears, a first central compound gear, and a first coupling gear disposed about a first input, the third and fourth gears coupled to the second and fourth lead screws, respectively, the first central compound gear including a distal gear and a proximal gear, the distal gear coupling the first and second gears with one another, thereby coupling the first and third lead screws with one another, the first coupling gear coupled with the proximal gear, the first input extending proximally from the second housing; and a third gear sub-assembly configured to engage the second gear sub-assembly, the third gear sub-assembly including a third housing (272, 274) at least partially capturing a second central compound gear and a second coupling gear disposed about a second input, the second central compound gear including a distal gear and a proximal gear, the distal gear coupling the third and fourth gears with one another, thereby coupling the second and fourth lead screws with one another, the second coupling gear coupled with the proximal gear, the second input extending proximally from the third housing, wherein the first input extends proximally through and from the third housing; wherein a rotational input provided to the first input rotates the first and third lead screws, and wherein a rotational input provided to the second input rotates the second and fourth lead screws.