# Orbital and Nasal Fractures

## Introduction
Orbital and nasal fractures are among the most common facial fractures encountered in plastic surgery. The orbit is a complex structure housing the globe, extraocular muscles, optic nerve, and lacrimal apparatus. Nasal fractures are the most common facial fracture overall; proper management prevents functional and aesthetic deformity. Naso-orbito-ethmoid (NOE) fractures represent a unique and challenging injury pattern requiring specialized management.

## Orbital Anatomy
The orbit is a pyramidal structure with the apex directed posteriorly and medially. **Seven bones** form the orbit: frontal, zygomatic, maxilla, lacrimal, ethmoid, sphenoid, palatine. **Orbital floor**: formed primarily by the maxillary bone (roof of maxillary sinus); thinnest area is posteromedial to the infraorbital groove. **Medial wall (lamina papyracea)**: the thinnest orbital wall (0.2-0.4 mm); formed by the ethmoid bone.

**Orbital volume**: approximately 30 mL; increase of as little as 1-2 mL causes clinically apparent enophthalmos. **Infraorbital nerve**: courses through the orbital floor in the infraorbital groove/canal; commonly injured in floor fractures. **Inferior rectus and inferior oblique muscles**: lie immediately above the orbital floor; at risk for entrapment.

## Orbital Floor Fractures (Blowout Fractures)

### Mechanism
**Hydraulic theory** (most accepted): direct blow to the globe increases intraorbital pressure, which is transmitted to the thin orbital floor causing fracture. **Buckling theory**: direct force to the inferior orbital rim causes buckling and fracture of the floor posterior to the rim. The inferior orbital rim remains intact in a pure blowout fracture (distinguishes from ZMC fracture).

### Clinical Presentation
**Diplopia**: most common complaint; binocular, worsens with upgaze. **Enophthalmos**: may be masked initially by edema; becomes apparent after swelling resolves (1-2 weeks). **Infraorbital nerve hypoesthesia**: numbness of the cheek, upper lip, and upper teeth ipsilaterally. **Periorbital ecchymosis and edema**: universal but nonspecific.

**Restriction of extraocular movements**: limited upgaze and downgaze; positive forced duction test. **Subcutaneous emphysema**: air from maxillary sinus; worsens with nose blowing or sneezing.

### Special Consideration: Trapdoor Fractures in Children
**White-eyed blowout fracture**: minimal periorbital signs but significant muscle entrapment. Greenstick fracture of the flexible pediatric bone creates a trapdoor that snaps back, trapping the inferior rectus or periorbital tissue. **Oculocardiac reflex**: vagal stimulation from muscle entrapment causes bradycardia, nausea, vomiting, syncope. **Surgical emergency**: requires urgent release (within 24-48 hours) to prevent irreversible muscle ischemia and permanent diplopia. Do NOT observe and wait in pediatric trapdoor fractures with restriction and oculocardiac reflex.

### Imaging
**CT scan with coronal and sagittal reformats**: gold standard; demonstrates fracture size, location, herniation of orbital contents, and muscle position. Look for: "teardrop sign" (herniated orbital fat/muscle into maxillary sinus), muscle thickening or entrapment, fracture size. **3D reconstruction**: helpful for surgical planning of complex fractures.

### Indications for Surgery
**Absolute**: muscle entrapment with restriction on forced duction test (especially in children), oculocardiac reflex. **Relative**: enophthalmos >2 mm (or predicted based on fracture size), large floor defect (>50% of the floor or >2 cm^2), persistent symptomatic diplopia in primary gaze, hypoglobus. **Observation appropriate for**: small fractures, diplopia that is improving, no entrapment on forced duction, no significant enophthalmos.

### Timing
Pediatric trapdoor fractures: operate within 24-48 hours (urgent). Adult fractures: typically 1-2 weeks to allow edema to resolve (unless entrapment present). Beyond 2-3 weeks, fibrosis makes reduction increasingly difficult.

### Surgical Technique
**Approach**: transconjunctival (preferred — no visible scar, lower ectropion rate) or subciliary (alternative). Transconjunctival may be preseptal or retroseptal; retroseptal avoids orbital septum and reduces ectropion risk. Lateral canthotomy added for additional exposure. **Fracture exploration**: periosteum elevated off the orbital floor; herniated contents reduced back into the orbit.

**Identify the posterior ledge**: critical landmark; stable bone at the posterior extent of the fracture defines the reconstruction scaffold. **Implant materials**: **Titanium mesh**: most commonly used; can be prebent and trimmed; rigid support; risk of globe injury if malpositioned. **Porous polyethylene (Medpor)**: rigid alloplast; allows tissue ingrowth; difficult to remove if infected.

**Resorbable plates** (PLLA/PGA): useful in children; resorb over 12-18 months. **Autogenous bone graft** (calvarial, iliac, conchal cartilage): biocompatible but adds donor site morbidity; resorption over time. **Forced duction test**: perform before and after implant placement to confirm no entrapment.

<image>Coronal cross-sectional illustration of an orbital blowout fracture and surgical repair. The left panel shows the normal anatomy with the intact orbital floor supporting the globe, inferior rectus muscle, and orbital fat. The right panel shows a blowout fracture with the orbital floor fractured and displaced inferiorly into the maxillary sinus, with orbital fat and the inferior rectus muscle herniating through the defect into the sinus (depicted as a teardrop of soft tissue hanging below the floor level). The globe is shown slightly sunken (enophthalmos). A third panel below shows the surgical repair: the herniated contents have been reduced back into the orbit, and a precontoured titanium mesh implant is shown spanning the fracture defect, resting on stable bone ledges anteriorly at the infraorbital rim and posteriorly at the posterior ledge. The globe position is restored to normal. Labels identify the globe, inferior rectus muscle, orbital fat, infraorbital nerve in its canal, maxillary sinus, fracture margins, and titanium mesh implant.</image>

## Medial Orbital Wall Fractures
Often occur in combination with orbital floor fractures. Isolated medial wall fractures are less common but may cause enophthalmos and medial rectus entrapment. **Clinical findings**: medial subconjunctival hemorrhage, restriction of abduction, enophthalmos, subcutaneous emphysema. Repair through transcaruncular or transconjunctival-with-swinging-eyelid approach. Reconstruct with titanium mesh or resorbable plates; endoscopic-assisted repair gaining popularity.

## Zygomaticomaxillary Complex (ZMC) Fractures
Also called "tripod" or "tetrapod" fractures; involves all four articulations of the zygoma. **Four fracture lines**: zygomaticofrontal suture, inferior orbital rim/floor, zygomaticomaxillary buttress, zygomatic arch. Clinical findings: malar flattening, trismus (impingement on coronoid process), lateral subconjunctival hemorrhage, step deformity at infraorbital rim, infraorbital nerve hypoesthesia. **Surgical indications**: displaced fractures with malar flattening, orbital floor involvement with entrapment/enophthalmos, trismus, significant step deformity.

**Fixation**: minimum two-point fixation for rotational stability; typically at zygomaticofrontal suture and zygomaticomaxillary buttress or infraorbital rim; three-point fixation for comminuted fractures. Approach: upper eyelid crease (ZF suture), transconjunctival or subciliary (infraorbital rim), and intraoral (ZM buttress). Zygomatic arch: Gillies temporal approach for isolated arch reduction; coronal approach for comminuted arch fractures.

## Nasal Fractures

### Anatomy
**Bony vault**: paired nasal bones articulating with frontal bone superiorly and maxillary frontal processes laterally. **Cartilaginous vault**: upper lateral cartilages, lower lateral cartilages (alar cartilages), septal cartilage. **Nasal septum**: perpendicular plate of ethmoid (superior), vomer (posteroinferior), quadrangular septal cartilage (anterior). Blood supply: Kiesselbach's plexus (Little's area) at the anterior septum — most common site of epistaxis.

### Classification
**Simple vs. comminuted**. **Unilateral vs. bilateral**. **With or without septal deviation/fracture**. **With or without septal hematoma**. Rohrich and Adams classification: based on direction of force and resulting fracture pattern.

### Clinical Evaluation
Inspect for deformity (swelling may mask — reassess at 5-7 days). Palpate for crepitus, step deformity, mobility of nasal bones. **Anterior rhinoscopy**: essential — evaluate for septal deviation, septal hematoma, mucosal tears. **Septal hematoma**: blood collection between septal cartilage and perichondrium; appears as a blue-purple, fluctuant, bilateral bulge.

**Surgical emergency**: must be drained immediately; undrained hematoma causes cartilage necrosis (avascular necrosis from loss of perichondrial blood supply) → saddle nose deformity. Treatment: incision and drainage, quilting sutures or nasal packing to prevent recurrence.

### Imaging
Plain films (nasal bones): poor sensitivity and specificity; often not useful. CT scan: not routinely needed for isolated nasal fractures; obtain if NOE fracture suspected, severe comminution, or associated midface injuries.

### Treatment
**Nondisplaced fractures**: observation; external splint for comfort. **Closed reduction**: indicated for displaced fractures; performed within 2 weeks (ideally 5-10 days after injury when swelling has subsided but before consolidation). Technique: topical and local anesthesia; Asch forceps or Boies elevator for intranasal reduction; Walsham forceps for septal fracture reduction. External nasal splint for 1-2 weeks.

Success rate approximately 60-70%; up to 50% have residual deformity requiring secondary rhinoplasty. **Open reduction**: rarely performed acutely; reserved for severe comminution or failed closed reduction. **Definitive septorhinoplasty**: recommended at 3-6 months if significant residual deformity persists after closed reduction.

## Naso-Orbito-Ethmoid (NOE) Fractures

### Anatomy and Classification

NOE fractures involve the confluence of the nose, orbits, and ethmoid sinuses. The **central fragment** bearing the medial canthal tendon (MCT) insertion is the key to classification. | Markowitz Type | Central Fragment | MCT Status | Treatment |
| --- | --- | --- | --- | --- |
| I | Single, large fragment | Intact attachment | Reduce and plate as a unit |  |
| II | Comminuted | Attached to identifiable fragment | Reduce, plate ± transnasal wire |  |
| III | Severely comminuted | Avulsed or on tiny unusable fragment | Transnasal canthopexy required |  |

**Markowitz classification**: **Type I**: single, large central fragment with intact MCT attachment; reducible as a unit.

**Type II**: comminuted central fragment but MCT still attached to a bone fragment; fragment can be reduced and plated. **Type III**: severely comminuted central fragment with MCT avulsed or attached to a tiny, unusable fragment; requires transnasal canthopexy.

### Clinical Findings
**Telecanthus**: increased intercanthal distance (normal: 30-35 mm); pathognomonic finding. Distinguish from hypertelorism (increased interorbital distance — bony). **Bowstring test**: lateral traction on the eyelid; normally the MCT snaps the eyelid back; loss of this snap indicates MCT disruption. Nasal flattening and widening; CSF rhinorrhea (cribriform plate fracture); epistaxis; periorbital ecchymosis.

### Surgical Treatment
All displaced NOE fractures require ORIF. **Type I**: reduce central fragment with plate fixation at the frontonasal and nasomaxillary buttresses. **Type II**: reduce and plate the fragment bearing the MCT; may need transnasal wire to supplement. **Type III**: transnasal canthopexy — wire passed through the MCT insertion, through the nasal septum, and secured to the contralateral medial orbital wall.

Wire must be placed posterior and superior to the lacrimal fossa (posterior to the posterior lacrimal crest) to recreate the normal MCT vector. Overcorrection is necessary; some relaxation always occurs. Bone grafting (dorsal nasal augmentation with cantilever calvarial bone graft) frequently needed for nasal projection. Lacrimal system may require stenting if canalicular injury is identified.

<image>Classification illustration of naso-orbito-ethmoid fractures based on the Markowitz system. Three panels show frontal views of the NOE region. Panel A (Type I) shows a single large central fragment on one side containing the medial canthal tendon attachment, depicted as a discrete bone piece with the tendon firmly attached, with fracture lines around it. The fragment can be reduced as a single piece. Panel B (Type II) shows a comminuted central fragment with multiple fracture lines breaking it into several pieces, but the medial canthal tendon remains attached to an identifiable bone fragment large enough to plate. Panel C (Type III) shows severe comminution with the medial canthal tendon either avulsed from bone or attached to a tiny fragment too small for plate fixation. An inset diagram shows the transnasal canthopexy repair technique: a wire passed through the medial canthal tendon, behind the posterior lacrimal crest, through the nasal septum, and secured to the contralateral medial orbital wall with appropriate vector posterior and superior to the lacrimal fossa. The normal intercanthal distance of 30-35 mm is labeled.</image>

## Complications
**Enophthalmos**: inadequate orbital volume reconstruction; 1 mL volume increase causes 0.8 mm enophthalmos. **Persistent diplopia**: 10-15% after orbital floor repair; usually resolves; may require strabismus surgery. **Ectropion**: from subciliary approach; minimize with skin-muscle flap technique, lateral canthopexy, or use transconjunctival approach. **Infraorbital hypoesthesia**: very common; majority recover over 6-12 months.

**Telecanthus**: undercorrection of NOE fracture; difficult to correct secondarily. **Saddle nose deformity**: missed septal hematoma or inadequate nasal dorsum reconstruction. **Epiphora**: lacrimal system injury; dacryocystorhinostomy if persistent. **Retrobulbar hemorrhage**: postoperative emergency; presents with proptosis, pain, vision loss; requires immediate lateral canthotomy and cantholysis.

## Key Clinical Pearls
Always perform a forced duction test before and after orbital floor repair; if restriction persists after implant placement, the implant is likely entrapping soft tissue and must be repositioned. A septal hematoma is a surgical emergency; missed hematoma leads to septal cartilage necrosis and permanent saddle nose deformity within days. In NOE fractures, the intercanthal distance must be measured and the bowstring test performed; telecanthus is the hallmark finding and requires transnasal canthopexy if the central fragment is severely comminuted (Type III). Pediatric orbital floor fractures with the oculocardiac reflex (bradycardia, nausea, vomiting) represent a surgical emergency requiring urgent fracture release to prevent irreversible inferior rectus ischemia. Nasal fracture reduction has a 30-50% rate of residual deformity; counsel patients that secondary rhinoplasty at 3-6 months may be necessary for optimal results.

## References
- Burnstine MA. Clinical recommendations for repair of isolated orbital floor fractures: an evidence-based analysis. Ophthalmology. 2002;109(7):1207-1210.
- Markowitz BL, Manson PN, Sargent L, et al. Management of the medial canthal tendon in nasoethmoid orbital fractures: the importance of the central fragment in classification and treatment. Plast Reconstr Surg. 1991;87(5):843-853.
- Rohrich RJ, Adams WP Jr. Nasal fracture management: minimizing secondary nasal deformities. Plast Reconstr Surg. 2000;106(2):266-273.
- Ellis E 3rd, El-Attar A, Moos KF. An analysis of 2,067 cases of zygomatico-orbital fracture. J Oral Maxillofac Surg. 1985;43(6):417-428.