Tobert DG, Davis BJ, Annis P, et al. - This retrospective, single-center case-controlled study was sought to correlate proximal junctional failure and mechanical failure rates between patients with ideal and non-ideal lordosis distribution index (LDI) cohort. Between 2001 and 2016, researchers enrolled adult individuals who had undergone surgical treatment for spinal deformity as defined by the SRS-Schwab criteria. A total of 187 patients were included in this study. For adult deformity, lumbar lordosis is an important parameter. Nevertheless, in this cohort, the LDI is an imperfect variable and previously developed categories did not reveal variations in failure rates.