Quick Facts
The common tendinous ring is a fibrous ring attached to the edge of the optic canal and the medial part of the superior orbital fissure that is the site of attachment of all four rectus muscles of the eye (Dorland, 2011).
Structure and/or Key Feature(s)
The common tendinous ring is a ring of fibrous tissue that surrounds the optic canal, partially extending over the superior orbital fissure.
Anatomical Relations
Many structures that enter the orbit via the optic canal or superior orbital fissure come to lie within the common tendinous ring. Those that enter the optic canal include the optic nerve and ophthalmic artery. Those passing through the superior orbital fissure include the oculomotor and abducens nerves, and the nasociliary branch of the ophthalmic nerve.
Function
The common tendinous ring provides the origin site form the four recti muscles (i.e., the superior, inferior, medial, and lateral recti muscles).
References
Dorland, W. (2011) Dorland's Illustrated Medical Dictionary. 32nd edn. Philadelphia, USA: Elsevier Saunders.
