| disease | Orbital Fracture |
Orbital fractures can occur alone or in conjunction with fractures of other maxillofacial bones, such as zygomatic fractures, frontal fractures, or maxillary Le Fort II and III fractures. Clinically encountered orbital fractures include orbital floor fractures, supraorbital rim fractures, orbital roof fractures, and fractures of the medial and lateral orbital walls. Among these, orbital floor fractures present certain distinctive features in diagnosis and treatment.
bubble_chart Etiology
The orbital floor is thin and weak, primarily composed of the orbital process of the maxilla, which forms the superior wall of the maxillary sinus, with the zygomatic orbital process located laterally. The orbital floor slopes upward and backward, with its posterior portion being the weakest area, traversed by the infraorbital canal and infraorbital fissure. This region connects with the lamina papyracea of the ethmoid bone, forming the inferomedial wall of the orbital floor, which is as thin as paper. When a fracture occurs in the midface due to external impact, the orbital floor is subjected to force, causing a sharp increase in intraorbital pressure that can lead to an orbital floor fracture (fracture of orbital floor). This type of fracture is also known as a blowout fracture. Since the maxillary sinus lies below the orbital floor, an orbital floor fracture often results in the herniation of orbital contents into the maxillary sinus.
1. Periorbital static blood and swelling may be caused by subcutaneous and subconjunctival hemorrhage around the orbit. If there is significant intraorbital hemorrhage, it can lead to proptosis. A step-like deformity is often palpable at the infraorbital rim, accompanied by tenderness.
2. Enophthalmos is an important sign of orbital floor fracture. The main causes of enophthalmos are: (1) Due to the orbital floor fracture, the orbital contents along with the eyeball are displaced downward or herniated into the maxillary sinus cavity; (2) The displaced orbital floor fracture fragments enlarge the orbital cavity, resulting in insufficient orbital fat to support the eyeball.3. Diplopia In blowout fractures, the orbital contents, including the inferior rectus muscle, inferior oblique muscle, and orbital septa, are displaced downward, restricting the vertical movement of the extraocular muscles and causing diplopia. If the oculomotor nerve is injured, it may also lead to diplopia.
4. Infraorbital numbness The fracture fragments of an orbital floor fracture often injure or compress the infraorbital nerve, causing numbness in the area supplied by this nerve. {|103|}
bubble_chart Treatment Measures
Surgical treatment should be performed in a timely manner. The optimal timing for surgery is approximately 1 week after the injury, as performing surgery too early may result in unresolved tissue swelling in the injured area, while delaying surgery may lead to malunion or scar formation, both of which can compromise the desired outcomes.
The goals of surgery are to reposition the incarcerated extraocular muscles and orbital fat, restore orbital volume and ocular motility, and improve enophthalmos and diplopia.
Surgical technique: Make a transverse incision below the lower eyelid eyelash, incising the skin and orbicularis oculi muscle without opening the orbital septum. Dissect downward along the orbital surface to the orbital rim. Below the orbital rim, make a horizontal incision through the periosteum and elevate the orbital floor periosteum along the bone surface to expose the orbital floor fracture site. Care must be taken to protect the infraorbital nerve. Meticulously and thoroughly dissect to free the inferior rectus muscle and orbital contents from the incarceration, allowing them to return to the orbital cavity. Perform a traction test to confirm unrestricted eye movement. If there is an infraorbital rim fracture, it should be reduced and fixed with interosseous wiring. For orbital floor bone defects, bone grafts or substitutes can be implanted to reconstruct the orbital floor.
1. Medical history: Patients with a history of blunt trauma to the eye from an object larger than the orbit or trauma causing multiple fractures in the midface should be evaluated for possible orbital floor fracture.
2. Midface fracture patients presenting with enophthalmos and diplopia.
3. Positive inferior rectus muscle traction test: After topical anesthesia with tetracaine, use ophthalmic forceps with teeth to grasp the inferior rectus tendon through the conjunctiva and perform a traction test. If upward movement of the eye is restricted, the test is positive, indicating inferior rectus muscle entrapment.
4. X-ray imaging: Waters' view or tomography can be selected to assess the orbital cavity, orbital floor, and maxillary sinus.
