Rod group, arcuate rod, s-shaped rod, spine stabilization system, and rod manufacturing method

An S-shaped rod for treatment of scoliosis and having that has an S-shaped curve comprising:

• a first curved section;
• and
• a second curved section that curves in an opposite direction to the first curved section,
• wherein
• the first curved section has a shape extending along thoracic kyphosis of an anatomically normal spinal column arrangement, and
• the second curved section has a shape extending along lumbar lordosis of an anatomically normal spinal column arrangement
• the S-shaped rod has (i) in a shape extending along thoracic kyphosis of an anatomically normal spinal column arrangement, a first curved section to be attached to thoracic vertebrae, and (ii) in a shape extending along lumbar lordosis of an anatomically normal spinal column arrangement, a second curved section to be attached to lumbar vertebrae, and
• the S-shaped rod has a shape for (i) guiding the postoperative apex of the thoracic kyphosis to be located at the thoracic vertebrae T6 to T8, and (ii) guiding the postoperative apex of the thoracic kyphosis to be located at a position different from a preoperative apex of the thoracic kyphosis.

A rod manufacturing method comprising:

• a rod data acquisition step of acquiring data indicating a plurality of rod shapes that was bent into shapes extending along anatomically normal spinal column arrangements;
• a length classification step of classifying data indicating the rod shapes acquired at the rod data acquisition step into groups of rod lengths with a difference of reference length;
• a rod shape acquisition step of acquiring data indicating best-fit curves from the rod shapes included in groups classified at the length classification step;
• and
• a rod making step of making rods used in spinal deformity correction and fusion, according to the best-fit curves acquired at the rod shape acquisition step.

A method for treatment of scoliosis comprising:

• a prediction step of predicting an anatomically normal spinal column arrangement without thoracic idiopathic scoliosis for a patient with thoracic idiopathic scoliosis;
• a rod attachment step of attaching to the spinal column of the patient a pair of rods having shapes extending along the spinal column arrangement predicted in the prediction step;
• a rod rotation step of rotating the attached pair of rods;
• wherein the method guides the postoperative apex of the thoracic kyphosis to the thoracic vertebrae T6 to T8 and guides the postoperative apex to a position different from a preoperative apex of the thoracic kyphosis.