What clinical finding may be present with a left infraorbital fracture due to facial trauma?

Infraorbital Fractures and Associated Clinical Findings

Hypoesthesia of the upper cheek is the most common clinical finding associated with infraorbital fractures due to trauma to the infraorbital nerve (V2).

Pathophysiology of Infraorbital Nerve Injury in Facial Trauma

Infraorbital fractures typically involve damage to the infraorbital rim and can extend to the orbital floor. These fractures frequently affect the infraorbital nerve due to its anatomical course through the infraorbital canal and foramen. When a patient sustains facial trauma resulting in an infraorbital fracture:

• The infraorbital nerve (branch of V2 - maxillary division of trigeminal nerve) is vulnerable to injury as it exits through the infraorbital foramen
• Fracture displacement can cause direct compression, stretching, or transection of the nerve
• The nerve may become entrapped in fracture fragments

Clinical Findings Associated with Infraorbital Fractures

Primary Finding:

• Hypoesthesia of the upper cheek - This is the most common neurological deficit, occurring in approximately 80% of patients with zygomatic complex fractures prior to treatment 1

Other Associated Findings:

• Limited upward gaze (as noted in the case presentation) due to:

  • Entrapment of orbital contents
  • Mechanical restriction from displaced bone fragments
  • Edema and hemorrhage in the orbital floor region

• Periorbital ecchymosis and edema

• Enophthalmos (posterior displacement of the globe)

• Facial asymmetry

• Diplopia (especially on upward gaze)

Diagnostic Considerations

CT maxillofacial scan is the gold standard for diagnosing infraorbital fractures 2, 3:

• Provides superior delineation of osseous structures
• Allows detection of subtle nondisplaced fractures
• Enables multiplanar and 3D reconstructions for better characterization of complex fractures
• Essential for determining the status of surrounding structures

Clinical Assessment of Infraorbital Nerve Function

When evaluating a patient with an infraorbital fracture:

1. Test light touch sensation over the upper cheek, lateral aspect of nose, and upper lip
2. Compare with the unaffected side
3. Document the degree of sensory deficit (mild, moderate, severe)
4. Monitor for progression of symptoms, as worsening hypoesthesia may indicate increasing compression 4

Prognosis and Recovery

The recovery pattern of infraorbital nerve function depends on several factors 5:

• Fracture displacement (nondisplaced vs. displaced)
• Direct nerve injury vs. indirect compression
• Timing of surgical intervention

Recovery statistics:

• Persistent hypoesthesia occurs in 22-50% of cases following treatment 1
• Midfacial fractures generally have better prognosis than mandibular fractures 5
• Recovery of nerve function may continue to improve even after one year following injury/surgery 1

Rare Complications

While hypoesthesia is the most common sensory disturbance, other sensory abnormalities can occur:

• Hyperesthesia (increased sensitivity) - rare but documented complication that may require surgical decompression if persistent 6
• Dysesthesia (abnormal sensation)
• Complete anesthesia (total loss of sensation)

Clinical Implications

The presence of infraorbital nerve hypoesthesia has important clinical implications:

• It serves as a diagnostic clue for infraorbital fractures
• Progressive worsening may indicate need for surgical intervention 4
• Persistent symptoms affect patient quality of life
• May require long-term follow-up and potentially nerve decompression in severe cases

In summary, when evaluating a patient with facial trauma and infraorbital fracture, clinicians should specifically assess for and document hypoesthesia of the upper cheek as this is the most common and clinically significant neurological finding associated with this injury.