Suspensory ligament of eyeball

At a glance

English

Suspensory ligament of eyeball

Latin (TA2)

Ligamentum suspensorium bulbi

System

Eye

Region

Head

Side

Paired, left and right

About the suspensory ligament of eyeball

The eyeball does not simply rest on the fat of the orbit. It is enclosed, from the optic nerve to near the corneal margin, by a thin fibrous envelope called the fascial sheath of the eyeball, or Tenon's capsule, which separates it from the orbital fat and forms a socket in which it can rotate. Below the globe this sheath is thickened into a hammock-like band known as the suspensory ligament of the eyeball, often called Lockwood's ligament after the surgeon who described it.

The band runs across the floor of the orbit beneath the eye. At each end it blends with a check ligament: medially with the expansion of the sheath over medial rectus, which attaches to the lacrimal bone behind the lacrimal crest, and laterally with the expansion over lateral rectus, which attaches to the orbital tubercle of the zygomatic bone. Between these anchors it widens beneath the globe and encloses, or fuses with, the sheaths of inferior rectus and inferior oblique at their crossing. In front it also sends fibres to the lower tarsal plate of the eyelid.

Its main job is support. Acting as a sling, it holds the eyeball up and forward in its normal position and resists downward displacement. It is strong enough that the globe keeps much of its height even when the bony floor of the orbit is broken or partly removed by surgery, as long as the ligament and its attachments remain intact. Because the inferior rectus and the lower lid retractors are bound to it, movements of the eye downward are coupled to a slight drop of the lower eyelid.

The ligament is relevant to operations on the two lower eye muscles, to repair of orbital floor fractures, and to operations on the lower eyelid, where its links with the lid retractors must be respected.

Function and supply

Begins at

Medially, by the medial check ligament from the lacrimal bone near the posterior lacrimal crest.

Ends at

Laterally, by the lateral check ligament to the orbital tubercle of the zygomatic bone.

Function

Supports the eyeball like a hammock, holding it up and forward in the orbit and preventing it from sinking downward.

Nerve supply

Sensory supply from orbital branches of the trigeminal nerve.

Blood supply

Small muscular branches of the ophthalmic artery to the two lower eye muscles, and the infraorbital artery.