This chapter comprehensively reviews the anatomy, embryology, biomechanics, classification, diagnosis and treatment of odontoid fractures, highlighting their complex structures and management. It explores the anatomy of the odontoid, detailing the specific roles and interactions of each component and emphasizing the ligaments and their role in protecting the spinal cord. Information concerning embryonic origins, anatomy, and morphometry is presented, detailing the essential contributions of the axis and the influence of biomechanics on odontoid fractures. The chapter addresses the clinical relevance of understanding these structures for imaging, diagnosis, and surgical interventions, stressing the importance of anatomy and embryology in healthcare fields. It therefore constitutes a valuable resource for medical staff, providing a comprehensive understanding of the odontoid and its biomechanics that is crucial for effective patient care and research progress.