[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Anatomy](https://durgical.com/en/anatomy/) › [Head and neck](https://durgical.com/en/anatomy/region/head-and-neck/) › Zygomatic bones [Skeletal system](https://durgical.com/en/anatomy/system/skeletal-system/) · [Head and neck](https://durgical.com/en/anatomy/region/head-and-neck/) # Zygomatic bones The zygomatic bones are the cheekbones; they form the outer rim of the eye sockets, shape the cheeks and anchor the masseter chewing muscle. Official name: Zygomatic bone [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=head_neck&select=zygomatic_bone&side=r) Opens in the Durgical app, no sign-up needed. ## What it is The cheekbones, forming the outer rim of the eye sockets. ## What it does Shape the cheek and anchor the masseter muscle. ## Key points - A zygomaticomaxillary complex (tripod) fracture breaks its links with the frontal, temporal (arch), maxillary and sphenoid bones and flattens the cheek - Signs: flat cheek, a step in the infraorbital rim, numb cheek and upper lip (infraorbital nerve, V2), lateral subconjunctival haemorrhage, trismus - An isolated zygomatic arch fracture often caves in a V shape onto temporalis and the coronoid process, limiting mouth opening - The lateral orbital (Whitnall) tubercle on the inside of the lateral orbital rim anchors the lateral canthal tendon ## Key facts **Joints with** Frontal, sphenoid, temporal (zygomatic arch), maxilla **Landmarks** Frontal, temporal and maxillary processes; lateral orbital rim; zygomatico-orbital, zygomaticofacial and zygomaticotemporal foramina (zygomatic nerve, V2) ## Relations **Medial** [Maxilla](https://durgical.com/en/anatomy/maxilla/) at the zygomaticomaxillary suture; the infraorbital foramen lies just below the orbital rim near this suture **Above** Zygomatic process of the [frontal bone](https://durgical.com/en/anatomy/frontal-bone/) at the frontozygomatic suture **Behind** Zygomatic process of the [temporal bone](https://durgical.com/en/anatomy/temporal-bone/), forming the zygomatic arch; the greater wing of the [sphenoid bone](https://durgical.com/en/anatomy/sphenoid-bone/) inside the orbit **Deep** [Temporalis](https://durgical.com/en/anatomy/temporalis-muscle/) and the coronoid process of the [mandible](https://durgical.com/en/anatomy/mandible/) under the arch; the temporal and infratemporal fossae **Superficial** [Zygomaticus major](https://durgical.com/en/anatomy/zygomaticus-major-muscle/) and minor arise from it; the [masseter](https://durgical.com/en/anatomy/superficial-part-of-masseter/) arises from the lower border of the arch ## How to find it The cheek prominence, the lateral orbital rim and the arch are all felt. Viewing both cheeks from above the head shows a flattened side, and a finger run along the infraorbital rim can find a step. ## Examination - Mouth opening: limited opening after a cheek injury suggests an arch fragment pressing on the coronoid process or temporalis - Eye movements and double vision: restricted upward gaze suggests the orbital floor is also broken, with tissue trapped - Sensation of the cheek, side of the nose and upper lip: reduced in infraorbital nerve injury ## On imaging Facial CT with coronal and 3D reconstructions is the standard; a submentovertex («jug-handle») radiograph shows the arch, and occipitomental views show the orbital rims and the maxillary sinuses. ## Clinical notes - Displaced complex fractures are reduced and fixed, often at the frontozygomatic suture, the infraorbital rim and the zygomaticomaxillary buttress - An isolated depressed arch can be lifted through a small incision in the temporal hairline (Gillies approach) - A subconjunctival haemorrhage whose back edge cannot be seen points to an orbital wall fracture ## Development Forms in membrane in the maxillary prominence of the first pharyngeal arch, usually from a single centre (some texts: up to three). In Treacher Collins syndrome it is small or missing, giving flat cheeks and down-slanting [eyelids](https://durgical.com/en/anatomy/superior-tarsus/). ## Related conditions - [Midface fractures (Le Fort, zygomatic, nasal)](https://durgical.com/en/conditions/midface-fractures/) - [Orbital floor (blowout) fracture](https://durgical.com/en/conditions/orbital-floor-fracture/) ## Test yourself Think of the answer, then tap the question to see it. ## What are the signs of a zygomaticomaxillary complex (tripod) fracture of the zygomatic bone? Flat cheek, a step in the infraorbital rim, numb cheek and upper lip (infraorbital nerve), lateral subconjunctival haemorrhage and trismus. ## Why can an isolated zygomatic arch fracture limit mouth opening? The arch often caves in a V shape onto temporalis and the coronoid process of the mandible. ## Through which approach is an isolated depressed zygomatic arch usually lifted? The Gillies approach: a small incision in the temporal hairline. ## Which tubercle on the zygomatic bone anchors the lateral canthal tendon? The lateral orbital (Whitnall) tubercle, on the inside of the lateral orbital rim. [Add to my cards (4)](https://durgical.app/estudiar/?add=/en/anatomy/zygomatic-bone/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** os zygomaticum TA2 818 **Official Spanish (DeCS)** Cigoma DeCS D015050 **English (TA2)** Zygomatic bone **Also called** cheekbone · malar bone · zygoma Sources: Terminologia Anatomica (TA2); [DeCS](https://decs.bvsalud.org/es/ths/resource/?id=15446); [Anatomy, Head and Neck, Zygomatic](https://www.ncbi.nlm.nih.gov/books/NBK544257/); [Anatomy, Head and Neck, Orbit Bones](https://www.ncbi.nlm.nih.gov/books/NBK531490/). ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/anatomy/zygomatic-bone/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/zygomatic-bone/