Transverse Ligament of the Atlas
Original Editor-Rachael Lowe
Top Contributors-Khloud Shreif,Rachael Lowe,Kim Jackson,Evan Thomas,Claire Knott,Tarina van der StocktandWikiSysop
Description[edit|edit source]
The transverse ligament of the atlas (TLA) is a thick, strong band of approximately 20mm in length[1]which arches across the ring of the atlas and maintains the odontoid process in contact with the anterior arch. It is concave in front, convex behind and broader at the middle than at the ends. The anterior surface of the ligament is covered with articular cartilage to allow articulation with the Odontoid process.
Attachments[edit|edit source]
It is attached on either side to a small tubercle on the medial surface of the lateral mass of theAtlas.
As it crosses the odontoid process, a small fasciculus (crus superius) is prolonged upward and another (crus inferius) downward, from the superficial or posterior fibers of the ligament. The former is attached to the basilar section of the occipital bone, in close relation with theTectorial membrane. The latter is fixed to the posterior surface of the body of theAxis;因此,整个韧带命名cruciform ligamentof the atlas.
Function[edit|edit source]
It is a very strong, primary stabiliser for the upper cervical spine - the odontoid process will generally fracture before theligamentwill tear.
It divides the ring of theAtlasinto two unequal parts: of these, the posterior and larger serves for the transmission of the spinal cord, its membranes, and the accessory nerves; the anterior and smaller contains theOdontoid process.
It functions to prevent anterior displacement of the C1 (atlas) over C2 (axis), the main stabilizer for the odontoid process preventing it from posterior migration.
Pathology[edit|edit source]
- Ossification of TLA isn't uncommon, however, it is presented in the elderly population[2], causes spinal cordmyelopathythat may need surgical intervention.
- It may also be included in medical conditions such asrheumatoid arthritis.
- Laxity of the ligament present in 14%- 22% ofDown syndrome.
- Rupture of TLA may occur inJefferson fracture(C1 fracture) and it is used to detect if the fracture is stable or non[1]. Types of ligament rupture according to Dickman's classification;
Type 1, there is a pure ligament tear and will need surgical fixation.
Type 2, called avulsion rupture, the rupture is from the lateral side of the atlas and needs a halo vest for a period of immobilization to heal.
Examination[edit|edit source]
References[edit|edit source]
- ↑1.01.1Vetter M, Oskouian RJ, Tubbs RS.“False” ligaments: a review of anatomy, potential function, and pathology. Cureus. 2017 Nov;9(11).
- ↑Sasaji T, Kawahara C, Matsumoto F.Ossification of transverse ligament of atlas causing cervical myelopathy: a case report and review of the literature. Case reports in medicine. 2011;2011.
- ↑nabil ebraheim. Cervical Spine injury, Transverse Ligament Injury - Everything You Need To Know - Dr. Nabil Ebraheim. Available from:http://www.youtube.com/watch?v=_nrQLEGZeBo[last accessed 8/12/2020]
