Abstract: A rod group includes a plurality of first rods that has an arcuate first curve, the first rods having mutually different lengths; and a plurality of second rods that has an S-shaped second curve, the second rods having mutually different lengths. The first rods and the second rods have shapes for treatment of scoliosis by (i) guiding the postoperative apex of the thoracic kyphosis to be located at the thoracic vertebrae T6 to T8, and (ii) guiding a postoperative apex of the thoracic kyphosis to be located at a position different from a preoperative apex of the thoracic kyphosis and the second rod each have a shape extending along an anatomically normal spinal column arrangement.

Abstract: A rod group includes a plurality of first rods that has an arcuate first curve, the first rods having mutually different lengths; and a plurality of second rods that has an S-shaped second curve, the second rods having mutually different lengths. The first rods and the second rods have shapes for treatment of scoliosis by (i) guiding the postoperative apex of the thoracic kyphosis to be located at the thoracic vertebrae T6 to T8, and (ii) guiding a postoperative apex of the thoracic kyphosis to be located at a position different from a preoperative apex of the thoracic kyphosis and the second rod each have a shape extending along an anatomically normal spinal column arrangement.

Abstract: A rod group includes a plurality of first rods that has an arcuate first curve, the first rods having mutually different lengths; and a plurality of second rods that has an S-shaped second curve, the second rods having mutually different lengths. The first rods and the second rods have shapes for treatment of scoliosis by (i) guiding the postoperative apex of the thoracic kyphosis to be located at the thoracic vertebrae T6 to T8, and (ii) guiding a postoperative apex of the thoracic kyphosis to be located at a position different from a preoperative apex of the thoracic kyphosis and the second rod each have a shape extending along an anatomically normal spinal column arrangement.

Abstract: A spine fixation device including an elongated bone screw partially embedded in a vertebra of a spine and a retaining head that can receive a rod and a head of the bone screw. The retaining head has an inner member that includes a screw head receiving section for receiving the screw head. The retaining head further has an outer member that includes an inner face that can contact an outer face of the screw head receiving section. When the inner face is in contact with the outer face, the screw head receiving section applies pressure to the screw head to fixate the relative angle between the bone screw and the retaining head.

Abstract: A spine fixation device including an elongated bone screw partially embedded in a vertebra of a spine and a retaining head that can receive a rod and a head of the bone screw. The retaining head has an inner member that includes a screw head receiving section for receiving the screw head. The retaining head further has an outer member that includes an inner face that can contact an outer face of the screw head receiving section. When the inner face is in contact with the outer face, the screw head receiving section applies pressure to the screw head to fixate the relative angle between the bone screw and the retaining head.