Fig. 38

This figure shows the corrective principles for a classic single structural thoracic curve with no lumbar or mild lumbar functional curve and spinal imbalance to the convex thoracic side (defined later as A2 type in Rigo classification). “Regional derotation” affects the main thoracic region against the lumbo-pelvic region and the proximal thoracic region. The main thoracic pad (level A) is narrower than in the previous case (A1 type). Consequently, the lumbar support (level D) is wider that in the previous case. Pelvic section is asymmetric also but closed on both sides, with a short left pelvic pad (just infra-iliac) and a right counter-trochanter pad (just supra-trochanter, with a specific shape to fix down the right trochanter. This pelvic design provides a stable fixation and level of the pelvis in the frontal plane. Proximal region is exactly like in the previous case (see Fig. 6). A1 and A2 type are both considered functionally three-curve scoliosis (see Rigo classification), so these two designs are also called “three curves brace design“ (3C). When a main structural thoracic curve is associated to a structural curve (always minor and more functional) and spinal balance is still to the convex thoracic side we still classify as three curves functional type or A3 type in Rigo classification. The design for A3 is like A2, just with a stronger lumbar support. A2 type design uses a main “three-point system” and a secondary “three-point system,” formed by the most caudal counter-trochanter pad, the medium left pelvic + lumbar support and the cranial right thoracic pad