The orbital part forms the outer elliptical band responsible for forced eye closure. Unlike the palpebral part (gentle closure), it produces the tight closure of grimacing and squinting.
| Origin | Nasal frontal bone, frontal process of maxilla, medial palpebral ligament |
|---|---|
| Insertion | Sweeps around the orbit and rejoins itself — forms a complete ellipse |
| Nerve Supply | Facial nerve — zygomatic and temporal branches (VII) |
| Blood Supply | Ophthalmic artery branches |
| Actions | Forceful eye closure — tight squinting; Contributes to periorbital wrinkling |
|---|
The orbital portion is targeted for botulinum injection to reduce crow's feet and treat essential blepharospasm. Facial nerve palsy affecting zygomatic and temporal branches produces lagophthalmos from orbital orbicularis loss — corneal exposure requiring lid loading or tarsorrhaphy.
Palpated around the orbital rim during forced eye closure.
Inability to close the eye from facial nerve palsy producing corneal exposure keratopathy, managed by lubricants, lid gold weight, and tarsorrhaphy.
