A New Radiological Sign for Severe Angular Kyphosis: “The Baltalimani Sign”

STUDY DESIGN: Retrospective diagnostic study. PURPOSE: To define a new radiological sign, “Baltalimani sign,” in severe angular kyphosis (SAK) and to report its relationship with the risk of neurological deficits and deformity severity. OVERVIEW OF LITERATURE: Baltalimani sign was previously undefined in the literature. METHODS: We propose Baltalimani sign as the axial orientation of the vertebrae that are located above or below the apex of angular kyphosis on anteroposterior radiographs. Patients with SAK of various etiologies with kyphotic angles ≥90° were selected and evaluated for the presence of Baltalimani sign. Demographic data of the patients including age, gender, etiology, neurological status, local kyphosis angles, and the location of the kyphosis apex were recorded. Sensitivity, specificity, positive predictive value (PPV), and negative predictive values (NPV) of Baltalimani sign for the risk of the neurological deficits were evaluated by the IBM SPSS ver. 20.0. A p-values of <0.05 were considered statistically significant. Cohen's kappa was used for analysis of interrater agreement. RESULTS: The mean local kyphosis angle in all patients was 124.2° (range, 90°–169°), and 15 of 40 (37.5%) patients had neurological deficits. Baltalimani sign was seen in 13 of 15 patients with neurological deficits (p=0.001). Baltalimani sign showed a sensitivity and specificity PPV and NPV of 61.9%, 86.7%, 89.5%, and 68.8% for the risk of the neurological deficits in SAK patients, respectively. Cohen's kappa value was moderate (κ=0.506). CONCLUSIONS: The detection of Baltalimani sign in SAK may indicate severity of deformity and the risk of neurological deficits.