Fractures of the zygomatic bone cause collapse of the zygomatic face. The zygomatic bone and zygomatic arch are the more prominent parts of the face and are susceptible to fracture by impact. The zygomatic bone is associated with the maxilla, frontal bone, pterygoid bone and temporal bone, of which the association with the maxilla is the largest, so zygomatic fractures are often accompanied by maxillary fractures. The temporal eminence of the zygomatic bone is connected to the zygomatic eminence of the temporal bone to form the zygomatic arch, which is narrower and more prone to fracture. Zygomatic-facial collapse examination 1, zygomatic-facial collapse The direction of fracture block displacement after fracture of zygomatic bone and zygomatic arch mainly depends on the direction of external force, and more inward displacement occurs. In the early post-injury period, zygomatic-facial depression can be seen; subsequently, due to local swelling, the depression deformity is not obvious and can be easily mistaken for simple soft tissue injury. When the swelling subsides after a few days, local collapse occurs again. Due to the internal displacement of the fracture block, the temporalis and occlusal muscles are compressed and the rostral protrusion is obstructed, resulting in painful mouth opening and mouth opening restriction. Zygomatic bone and zygomatic arch fractures are internally displaced and restrict mouth opening. (1) The zygomatic bone is displaced to compress the rostral process; (2) The zygomatic arch is invaginated to obstruct the rostral process movement. 3. Diplopia The zygomatic bone forms the majority of the lateral orbital wall and infraorbital rim. Diplopia can be found after displacement of the zygomatic fracture due to displacement of the eye, bleeding and local edema of the adductor muscle, and a torn inferior oblique muscle embedded in the fracture line, limiting eye movement. 4. Petechiae When there is a closed fracture of the orbital wall of the zygoma, there may be hemorrhagic petechiae under the periorbital skin, eyelids, and conjunctiva. 5. Neurological symptoms A fracture of the maxillary process of the zygomatic bone may damage the infraorbital nerve, resulting in a numbness in the area innervated by this nerve. If the zygomatic branch of the facial nerve is also damaged during the fracture, incomplete eyelid closure may occur. The diagnosis of zygomatic arch fracture can be made based on the history of injury, clinical features and radiographic examination. On palpation, the fracture may have localized pressure pain, collapse and displacement, and there may be a step formation at the zygomatic-frontal suture, the zygomatic-maxillary suture bone junction, and the infraorbital rim. If the fracture is palpated from inside the mouth along the vestibular sulcus and posteriorly, the space between the zygomatic bone and the maxilla and rostral process can be examined to see if it has become smaller. Radiographs are often taken in the nasal-chin and zygomatic arch positions. In the nasal-chin position, the fracture of the zygoma and zygomatic arch can be seen, and the orbit, maxillary sinus and infraorbital foramen can be observed for abnormalities. In the zygomatic arch position, the fracture and displacement of the zygomatic arch can be clearly shown. The zygomatic arch fracture can be divided into zygomatic fracture, zygomatic arch fracture, combined zygomatic-zygomatic arch fracture and complex fracture of zygomatic and maxillary bones, and zygomatic arch fracture can be divided into bilinear and trilinear fractures. knight and north proposed 6 types of classification: (1) undisplaced fracture; (2) zygomatic arch fracture; (3) zygomatic body fracture displaced inward and downward without transposition; (4) internal transposition of zygomatic body fracture, counterclockwise to the left, clockwise to the (4) internal transposition of the zygomatic body fracture, with the left side rotating counterclockwise and the right side rotating clockwise or toward the midline, and the radiograph showing the infraorbital rim downward and the zygomatic frontal process displaced medially; (5) external transposition of the zygomatic body fracture, with the left side rotating clockwise and the right side rotating counterclockwise or away from the midline, and the radiograph showing the infraorbital rim upward and the zygomatic frontal process displaced laterally; (6) complex fracture. It is considered that (2) and (5) fractures are stable after reduction and do not require fixation; (3), (4) and (6) fractures are unstable after reduction and require fixation.