The Contribution of the Double Rib Contour Sign and the Rib Index to the Study of Scoliogeny, Thoracic Deformity, Progression, Outcome of Treatments and Costoplasty for Idiopathic Scoliosis.

This opinion article refers to the "double rib contour sign" and to the rib index (DRCS and RI), to their reliability study results in the chest radiographs of a control group and to their validity study results. These two parameters were introduced by the first author in this report. The introduction of the Segmental Rib Index (SRI) and its relation to spinal deformity is also discussed. The RI has been confirmed to be a strong surrogate for scoliometric readings in idiopathic scoliosis (IS). The clinical applications of the RI are analyzed for the following: (a) the documentation of deformity; (b) the assessment of physiotherapy outcomes (PSSEs); (c) the documentation of the outcomes of brace treatment; (d) the documentation of the pre- and post-operative assessment of thoracic deformity correction in different types of instrumentation; (e) its usage in prognosticating accelerated deterioration in skeletally mature adolescent idiopathic scoliosis (AIS) curves of 40-50 degrees; and (f) its usage in the recognition of the proper rib level for thoracoplasty/costoplasty. The emerging etiological-scoliogenic implications from the use of the DRCS and RI are described. The rotation of the trunk and vertebral bodies as interrelated, but distinct parameters are finally analyzed.