Posterior spinal fixation screws

A bone screw assembly comprising:

• a first bone screw comprising:
• a first bone screw shank comprising a first shank head and a first dual-head receiver, the dual head receiver comprising:
• a first receiver comprising a first base having a first cavity therewithin, the first cavity configured to securely receive the first shank head, a first pair of arms extending upwardly from the first base, and a first rod channel defined between the first pair of arms;
• a second receiver comprising a second base having a second rod channel defined between a second pair of arms;
• and
• a first connection between the first receiver and the second receiver, wherein the first connection is integral to the first receiver and moveable relative to the second receiver,
• wherein the first connection is integral with one arm of the first pair of arms, wherein the second receiver is movably coupled with the first connection, wherein the second receiver comprises a slot in one arm of the second pair of arms, wherein the first connection extends through the slot and permits translation of the second receiver relative to the first connection, wherein relative to the first connection the second receiver is movable in multiple dimensions including roll, pitch and yaw, wherein the first connection comprises a taper in the direction of lateral extension from the one arm of the first pair of arms toward the second receiver, wherein a second arm of the second pair of arms is closed at an outer surface thereof such that the connection does not extend through the second arm;
• and
• a second bone screw comprising:
• a second bone screw shank comprising a second shank head and a second dual-head receiver, the second dual head receiver comprising:
• a third receiver comprising a third base having a second cavity therewithin, the second cavity configured to securely receive the second shank head, a third pair of arms extending upwardly from the third base, a third rod channel defined between the third pair of arms;
• a fourth receiver comprising a fourth base having a fourth rod channel defined between a fourth pair of arms;
• and
• a second connection between the third receiver and the fourth receiver;
• and
• a first rod securely received in the second rod channel and the fourth rod channel thereby securely connecting the first bone screw and the second bone screw, wherein the first rod channel extends in a first direction, and the second rod channel extends in a second direction substantially parallel to the first direction.

A bone screw comprising:

• a bone screw shank comprising a shank head;
• a dual-head receiver comprising:
• a first receiver comprising a first base having a cavity therewithin, the cavity configured to securely receive the shank head, a first pair of arms extending upwardly from the first base, and a first rod channel defined between the first pair of arms;
• a second receiver comprising a second base having a second rod channel defined between a second pair of arms;
• and
• a connection between the first receiver and the second receiver, wherein the connection is integral to the first receiver and moveable relative to the second receiver, wherein the connection is integral to one arm of the first pair of arms and is movable relative to the second pair of arms,
• wherein the connection between the first receiver and the second receiver extends laterally from an outer surface of the one arm of the first pair of arms,
• wherein the second receiver is movably coupled with the connection, wherein the second receiver comprises a slot in one arm of the second pair of arms, wherein the connection extends through the slot and permits translation of the second receiver relative to the connection, wherein relative to the connection the second receiver is movable in multiple dimensions including roll, pitch and yaw, wherein the connection comprises a taper in the direction of lateral extension from the one arm of the first pair of arms toward the second receiver,
• wherein the second receiver is rotatable about an axis of the connection to position the second receiver at an acute angle relative to the axis of connection,
• wherein a gap exists between the second receiver and the first receiver during movement of the second receiver in each of the multiple dimensions, and
• wherein a second arm of the second pair of arms is closed at an outer surface thereof such that the connection does not extend through the second arm.