Orbital blowout fracture

The orbit is a rigid bony space with thin walls separating the eye and its surrounding tissues from the paranasal sinuses. A blunt impact can fracture the floor or medial wall, sometimes leaving the orbital rim intact. Fat and soft tissues may move through the defect, altering eye position or restricting movement. The phrase blowout describes the fracture pattern rather than its severity. A small fracture can incarcerate tissue tightly, while a larger defect may produce later enophthalmos without acute muscle strangulation.

Assessment starts with the eye and the patient as a whole. Check for associated head, neck and facial injury, then document acuity, pupils, movement, diplopia and the ability to open the eye. An afferent pupillary defect or vision loss not explained by surface injury requires urgent ophthalmology input. Increasing proptosis, tense lids and rapidly worsening vision suggest orbital compartment syndrome and require immediate management rather than waiting for the fracture scan. An obvious globe wound requires shielding and avoidance of pressure. Several of these injuries can coexist.

Floor injury may affect the infraorbital nerve, causing altered sensation over the cheek, upper lip and upper teeth. Diplopia can arise from swelling, haemorrhage, muscle contusion or actual entrapment; restricted movement does not automatically identify which mechanism is present. Ask in which gaze positions the double vision occurs and whether either eye alone sees a single image. Examine movement gently rather than repeatedly provoking severe pain or a vagal response. Specialist orthoptic assessment quantifies movement and binocular function during recovery.

Children's more elastic orbital bones can spring back after fracturing and trap tissue in a narrow defect. The external eye may be relatively white, creating a misleading impression of a minor injury. Painful restricted movement with nausea, vomiting, pallor or bradycardia may reflect the oculocardiac reflex from traction on trapped tissue. These features can be mistaken for concussion or gastrointestinal upset. The child needs urgent joint assessment and potential surgical release, not routine review after bruising settles. CT findings can be subtle, so communicate the clinical concern directly to radiology and the treating teams.

CT with orbital or facial reconstructions demonstrates the fracture, herniated tissue, sinus involvement and associated haemorrhage. Imaging helps plan surgery but must be matched to vision, pupils, motility and symptoms. A radiology statement of a small fracture does not establish that movement is safe. MRI is not the initial bony trauma investigation and should not be used when retained metallic material is possible. Forced-duction testing is a specialist procedure, undertaken where appropriate after globe integrity and patient safety have been considered.

Many adults with uncomplicated fractures improve as swelling resolves and do not need immediate surgery. Reassessment commonly occurs after about a week, with the exact appointment set by the treating service. Persistent functionally important diplopia, enophthalmos, hypoglobus or a defect likely to disturb orbital support may lead to repair. Entrapment and acute visual threats require a faster pathway. The decision should consider the patient's work, binocular needs and preferences as well as imaging; there is no single fracture-size rule that replaces that assessment.

Explain sinus precautions clearly. Nose blowing can force air through the fracture into soft tissues or the orbit; sneeze with the mouth open and avoid actions that deliberately pressurise the nose. Analgesia, an appropriate cold compress without globe pressure and activity advice may be used after serious eye injury has been excluded. Antibiotic and decongestant decisions follow the injury characteristics and local surgical pathway rather than an automatic identical prescription for every closed fracture. Provide a route for urgent review if swelling, pain or vision suddenly worsens.