Ligament maintaining Atlantoaxial stability is:
Ans: A (Transverse ligament) Ref: Gray's Anatomy. 39th edition, 2005, Page 760 & 761Explanation:The most important factors maintaining stability are the ligaments, of which the transverse atlantal ligament is the strongest. The alar ligaments are weaker. Other ligaments connecting the axis and the occipital bone, the fibrous capsules, the ligamentum nuchae and the posterior neck muscels aiso contribute to stability; the suboccipital muscles play an important proprioceptive and postural role." Ref: Gray's AnatomyFactors maintaining stability of atlanto-axial joint:LigamentsPosterior neck muscles {suboccipital muscles}.Ligaments:Ligaments connecting atlas with axis :Transverse atlantal ligament (strongest).Transverse component of cruciform ligament.Ligaments connecting axis with occipital bone:Longitudinal component of cruciform ligamentApical ligamentAlar ligament (weakest)Mem bran a tectoriao Fibrous capsule of the jointo Ligamentum nuchae.Transverse atlantal ligament:It is the strongest ligament which maintain the stability of atlanto-axial joint.Isa broad, strong band which arches across the atlantal ring behind the dens.Attachment: tubercle on the medial side of each atlantal lateral mass.It is covered anteriorly by a thin layer of articular cartilage.It consists almost entirely of collagen fibres and in the central part of the ligament fibres cross one another at an angle to form an interlacing mesh.The transverse ligament divides the ring of the atlas (vertebral foramen} into 2 parts.The posterior 2/3 surrounds the spinal cord and meninges and anterior 1/3 contains the dens.It retains the dens in position even when all other ligaments are divided.Note:Anatomist's say even though the heart and lungs are the most important vital organs, we are kept alive by the integrity of 2 muscles and 1 ligament!!!2 Muscles:1. Genioglossus (safety musde of tongue - protrusion of tongue).2. Posterior cricoarytenoid (safety muscle of larynx - abductor of vocal oord).1 Ligament: Transverse atlantal ligament (safety ligament of lower medulla/spinal cord) intactness of this ligament prevent the dislocation of dens and thereby preventing the injury to lower part of medulla oblongata.Fig: Transverse atlantal ligament
Transverse ligament
Tectorial ligament
Alar ligament
Apical ligament
Osteology of Head and Neck