Reassessing the Application of the Haller Index as a Surgical Indicator for Pectus Excavatum

Pectus excavatum, or "funnel chest," is the most common congenital chest wall deformity, characterized by posterior depression of the sternum and adjacent costal cartilages. Although frequently identified in childhood, the deformity often progresses during adolescence and may lead to exercise intolerance, respiratory symptoms, and psychosocial distress. Traditionally, surgical indications have been guided by the Haller index, a radiographic metric derived from chest computed tomography (CT) scans, although its reliability in predicting functional compromise remains debated. This retrospective study evaluated 41 Hispanic pediatric patients with pectus excavatum (mean age 14.1 years), of whom 36 of 41 (88%) were male, who were seen at Puerto Rico Children's Hospital between 2015 and 2021. Spirometry values, including forced vital capacity (FVC) and forced expiratory volume in one second (FEV₁), were compared across Haller index categories (<3.25 vs ≥ 3.25). No statistically significant correlation was found between the Haller index and individual spirometry parameters, consistent with weak Pearson correlation coefficients (r = -0.26 for FVC and r = -0.14 for FEV₁). Receiver operating characteristic (ROC) analysis demonstrated limited ability of the Haller index to identify reduced FVC (AUC = 0.63). These findings suggest that the Haller index alone is insufficient as a standalone surgical indicator for pectus excavatum. A comprehensive evaluation incorporating dynamic cardiopulmonary assessment, psychological considerations, and refined imaging tools such as the correction index may better inform surgical decision-making.