Séptima y octava vértebra plana dorsal ¿una forma nueva de espondiloartropatía? Diagnóstico certero

Resumen

Introduction: The spine is an articulated mechanical structure that arranges its vertebral bodies with a progressive increase in size from the cervical to the lumbar region. Force overloads in various planes can cause growth asymmetries, but uniform flattening can rarely be considered a developmental defect, so that its presence is fully considered a pathological condition. The concept of flat vertebra was introduced by Calvé in 1925, but it was not until 1990 that it was extended by Rimoin to include dysplastic diseases, defined by flattening or wedging, and irregular surfaces or Schmorl's nodules, a concept that is not very rigorous and needs to be updated. We describe a pathology that is related to non-inflammatory spondyloarthropathies dependent on spondyloarthropathies, in which flattening of the seventh and eighth dorsal vertebrae is observed, associated with radiological manifestations suggestive of mutations in the type II procollagen gene (COL2A1). Our working hypothesis is based on the fact that chondrodysplastic rheumatism consisting of a flattening of the seventh and eighth dorsal vertebrae could be considered as a new form of spondyloarthropathy. The aims of the study, therefore, are to find populations affected by this pathology, to determine the associated clinical and radiological manifestations, and to describe anthropometric indices that eliminate the ambiguity of the observer, as well as their strength, sensitivity and specificity. Material and method: The study design is case-control. The Control Group (90 volunteers) is obtained from the outpatient clinics of the Allergy and Endocrinology Service, and the Pathological Group (84 patients), diagnosed with seventh and eighth dorsal flat vertebrae, following the Rimoin criteria, and with at least one of the clinical-radiological manifestations suggestive of type II collagen alterations, or their relatives with dorsal flat vertebrae without other findings. Three anthropometric indices (IV1, IV2 and IV3) were created, two measurements were taken on the eighth dorsal vertebra (height and length), and gender, age, stratified age, weight, height, BMI, obesity, and marked obesity were recorded as other independent variables. Results: In the descriptive study of the clinical-radiological manifestations, it is observed that the most frequent, in isolation, are atypical osteoarthritis, low dorsal kyphotic apex, and scoliosis; and in combination, the multiple association of two or three, as opposed to one or the sum of four alterations. The IV2 index is the most robust with a sensitivity and specificity of over 90% for IV2 equal to 11.1 m-1 in the Pathological Group. Conclusions: The flattening of the seventh and eighth dorsal thoracic vertebrae could be considered an axial radiological manifestation, within a possible noninflammatory spondyloarthropathy dependent on spondyloarthropathies, considering that the Rimoin criteria for the diagnosis of vertebral dysplasia are ambiguous. With the IV2 anthropometric index ≥11.1 m-1, a sensitivity and specificity of more than 90% is obtained in the diagnosis of vertebral flattening of the eighth dorsal vertebra, in which the flat vertebra dominates over the disharmony of the individual and its vertebra.