A blowout fracture occurs when one or more bones surrounding the eye breaks. Usually, a direct blow to the eye, specifically the central orbit, from an object like a ball, fist, etc., may cause the fracture. Despite the fracture, the orbital rim remains intact. When force is transferred into the eye compartment, the thinnest bones in the orbit may break. The bone that often breaks is found on the floor or bottom of the orbit.
Children are most affected by blowout fracture because of their bone elasticity. They usually end up with a special type of fracture called a 'white-eye fracture' or 'trapdoor.' The force creates a hinged bone fragment that opens and allows the escape of soft tissue but then shuts like a trapdoor. Eye movement is then seriously restricted because the tissue that was trapped loses its blood supply. If the blow is severe, it can cause the eye to sink back into the orbit. The affected person can also suffer from diplopia or double vision, where they see two images simultaneously.
Blowout fracture can be categorized according to its features, such as:
- Size, big or small
- Location, front or back
- Bone, displaced or still in place
- Tissue/muscle, if entrapped in the fracture
- Accompanying symptoms like pain, the position of the eye, double vision, etc
Blowout fracture can also be classified according to the origin, i.e., whether it occurred through one or more of the orbital walls, and includes:
- Medial wall
- Lateral wall
- Inferior, the floor of the orbit wall
- Superior, the roof of the orbit wall
Causes & Risk Factors
Blowout fracture is caused by force from an object that hits the bones of the orbit. Usually, the object is large enough and is at a high speed. Great force can cause the bone to buckle and break. Force can come from a baseball or soccer ball during sports, motor vehicle accidents, fights with elbows and fists, falls, and so on.
Risk factors may include:
- Boys more than girls
- Sinuses in children below seven years old if the sinuses do not fully develop while the children are growing up
Signs & Symptoms
Signs of blowout fracture may include:
- Air below the skin that surrounds the eye
- Decreased upward and downward eye movements
- A disrupted orbital floor’s contour so that it’s no longer smooth to the touch
Symptoms of blowout fracture may include:
- Eye redness
- Double vision
- Nausea and vomiting
- Cheek, teeth, or nose numbness
- Pain when there is eye movement
- The area around the eye is bruised, tender, or swollen
Diagnosis of blowout fracture may include:
- Taking down medical history. This includes a history of how the injury occurred and what object was responsible. A history of symptoms is also relevant. For example, if the patient experiences pain when the eye moves vertically. Other symptoms whose history is relevant include if diplopia is present on vertical gaze, swelling of the eyelid, tenderness, and if after blowing the nose, there is crepitus (grating, crackling, popping sound)
- A physical examination where the doctor assesses the condition of the eye and will look for things like restricted movement leading to diplopia
- A complete eye examination where the doctor looks for evidence of the injury such as subconjunctival hemorrhage, retinal detachment, etc.
- Depending on the mechanism and extent of the injury, the doctor may recommend imaging tests. One is computed tomography of the brain and orbit. Magnetic resonance imaging may also be used if the patient was exposed to radiation
For simple fractures, oral steroids are used to help reduce the swelling and heal the scar. Sometimes, oral antibiotics may be used in case infection is suspected. The sinuses can be drained using decongestants. Draining ensures that the fluid and blood do not accumulate in the sinuses.
Surgical treatment may not be necessary for most simple blowout fractures. Often, these do not cause lasting problems and will heal. However, it is considered in trapdoor fractures, where the tissue trapped inside is removed in one to two days. Patients with persistent symptoms can also have surgery. However, other fractures only require observation because diplopia usually improves over several weeks.
Ice can be applied to reduce the swelling. The patient is advised to avoid blowing out the nose. This will help prevent sinus contents from spilling into the orbit as a result of that pressure.
Prognosis & Long-Term Outlook
If double vision persists, strabismus or eye muscle surgery may be necessary. Non-surgical methods such as botulinum toxin injections or prism glasses may be used to treat double vision.
Prevention & Follow Up
If there is suspicion of an orbital floor fracture, the patient may be referred to an ophthalmologist or maxillofacial surgeon. Follow-up can take place a week after the traumatic event to rule out enophthalmos or diplopia.