Coexisting median canaliform nail dystrophy and habit-tic deformity

Introduction: Median canaliform nail dystrophy (MCD) and habit-tic deformity (HTD) are nail abnormalities that share overlapping clinical and pathogenetic features, and may represent a spectrum of trauma-induced nail disorders. However, their coexistence in the same patient is rarely reported. Case Report: We describe a 42-year-old man presenting with concurrent MCD and HTD affecting the thumbnails. Conclusion: This case highlights the diagnostic challenges in differentiating between these conditions and supports the hypothesis that they may share a common underlying pathogenesis.