Orbital Fractures

Overview

Definition

An orbital fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures is a broken bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Structure of Bones involving the eye socket, either in the orbital rim, the orbital floor, or both.

Epidemiology

• Orbital fractures account for approximately 3% of all patients seen in the ED.
• More common in men than in women (4:1)
• More common in adults than in children
• Average age: 30 years

Etiology

• The most common cause of orbital fractures is blunt force trauma to the eye.
• About 85% of traumatic eye injuries (including orbital fractures) are caused by:
  • Auto accidents: most common cause of maxillofacial trauma
  • Contact sports
  • Occupational accidents
  • Home repair projects
• About 15% are due to violent assaults.
• For fractures in adult women, it is important to assess for domestic violence. 

Anatomy and Pathophysiology

To understand the pathophysiology of orbital fractures, it is important to understand the anatomy of the orbit Orbit The orbit is the cavity of the skull in which the eye and its appendages are situated. The orbit is composed of 7 bones and has a pyramidal shape, with its apex pointed posteromedially. The orbital contents comprise the eye, extraocular muscles, 5 cranial nerves, blood vessels, fat, the lacrimal apparatus, among others. The Orbit and Extraocular Muscles, the clinical presentation, and the potential consequences of fractures.

Anatomy

The 7 bones of the orbit Orbit The orbit is the cavity of the skull in which the eye and its appendages are situated. The orbit is composed of 7 bones and has a pyramidal shape, with its apex pointed posteromedially. The orbital contents comprise the eye, extraocular muscles, 5 cranial nerves, blood vessels, fat, the lacrimal apparatus, among others. The Orbit and Extraocular Muscles are:

• Maxilla
• Zygomatic
• Frontal
• Ethmoid
• Lacrimal 
• Sphenoid
• Palatine 

The walls of the orbit Orbit The orbit is the cavity of the skull in which the eye and its appendages are situated. The orbit is composed of 7 bones and has a pyramidal shape, with its apex pointed posteromedially. The orbital contents comprise the eye, extraocular muscles, 5 cranial nerves, blood vessels, fat, the lacrimal apparatus, among others. The Orbit and Extraocular Muscles are: 

• Superior (roof): made up of the orbital part of the frontal bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Structure of Bones and the lesser wing of the sphenoid
• Medial: made up of the frontal process of the maxilla, the lacrimal bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Structure of Bones, the orbital plate of the ethmoid bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Structure of Bones, and the sphenoid body
• Inferior (floor): made up of the maxillary, zygomatic, and palatine bones
• Lateral: made up of the greater wing of the sphenoid, the orbital part of the frontal bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Structure of Bones, and the frontal process of the zygomatic bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Structure of Bones

Pathophysiology

There are 4 main types of orbital fractures, which are classified on the basis of the anatomy involved.

• Orbital zygomatic fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures: 
  • Zygomatic region of the orbit Orbit The orbit is the cavity of the skull in which the eye and its appendages are situated. The orbit is composed of 7 bones and has a pyramidal shape, with its apex pointed posteromedially. The orbital contents comprise the eye, extraocular muscles, 5 cranial nerves, blood vessels, fat, the lacrimal apparatus, among others. The Orbit and Extraocular Muscles is the most common location of an orbital rim fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures.
  • Most common cause: a high-impact blow to the lateral orbit Orbit The orbit is the cavity of the skull in which the eye and its appendages are situated. The orbit is composed of 7 bones and has a pyramidal shape, with its apex pointed posteromedially. The orbital contents comprise the eye, extraocular muscles, 5 cranial nerves, blood vessels, fat, the lacrimal apparatus, among others. The Orbit and Extraocular Muscles
• Nasoethmoid fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures: 
  • Fracture of the medial wall of the orbit Orbit The orbit is the cavity of the skull in which the eye and its appendages are situated. The orbit is composed of 7 bones and has a pyramidal shape, with its apex pointed posteromedially. The orbital contents comprise the eye, extraocular muscles, 5 cranial nerves, blood vessels, fat, the lacrimal apparatus, among others. The Orbit and Extraocular Muscles
  • Often associated with fractures of the orbital floor
  • Due to direct force applied to the nasal bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Structure of Bones
• Orbital roof fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures:
  • Location: frontal bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Structure of Bones (roof of the orbit Orbit The orbit is the cavity of the skull in which the eye and its appendages are situated. The orbit is composed of 7 bones and has a pyramidal shape, with its apex pointed posteromedially. The orbital contents comprise the eye, extraocular muscles, 5 cranial nerves, blood vessels, fat, the lacrimal apparatus, among others. The Orbit and Extraocular Muscles)
  • Frequently associated with intracranial injuries 
• Orbital floor fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures: 
  • “Blowout fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures”
  • Location: maxillary, zygomatic, and palatine bones 
  • Ocular motility may be disrupted, as orbital tissue is commonly involved.

Clinical Presentation

In a patient presenting with possible orbital fractures, it is important to identify life-threatening and/or serious associated injuries, especially intracranial injury and cervical spine fractures.

History and symptoms

• History of blunt (more common) or penetrating trauma
• Diffuse orbital pain Pain Pain has accompanied humans since they first existed, first lamented as the curse of existence and later understood as an adaptive mechanism that ensures survival. Pain is the most common symptomatic complaint and the main reason why people seek medical care. Physiology of Pain 
• Pain on movement of the eyes suggests injury to the extraocular muscles.
• Diplopia on upward gaze suggests injury to the orbital floor.
• Numbness of the forehead suggests injury to the orbital roof.
• Nausea can be caused by entrapment of extraocular muscles.

Physical examination findings

• Periorbital edema Edema Edema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema
• Ecchymosis 
• Diplopia: due to mechanical entrapment of both inferior oblique and inferior rectus muscles
• Absent pupillary light reflex if damage to the afferent nerves
• Enophthalmos: posterior displacement of the eyeball within the orbit Orbit The orbit is the cavity of the skull in which the eye and its appendages are situated. The orbit is composed of 7 bones and has a pyramidal shape, with its apex pointed posteromedially. The orbital contents comprise the eye, extraocular muscles, 5 cranial nerves, blood vessels, fat, the lacrimal apparatus, among others. The Orbit and Extraocular Muscles, seen in blowout fractures
• Proptosis: protrusion of the eyeball, seen in orbital zygomatic fractures
• Widened intercanthal distance due to disruption of the medial canthal ligament
• Bradycardia: associated with the “oculocardiac reflex” (a reduction in pulse rate associated with pressure applied over extraocular muscles)

Diagnosis

Ocular injuries are present in up to 29% of patients with orbital fractures. It is imperative that an ocular exam be done as soon as possible to mitigate the risk of vision loss.

Ocular examination

• Visual acuity
• Ocular motility
• Intraocular pressure
• Slit-lamp examination to visualize any retinal damage
• Visual field examination

Imaging

• X-ray:
  • Screening to identify fractures
  • Water’s view (also known as the occipitomental view): X-ray beam is angled at 45 degrees and shows “teardrop sign” in antrum.
• CT scan:
  • Gold standard for detection of orbital fractures
  • Thin slices < 2 mm are preferred. 
  • Coronal and sagittal views differentiate between periorbital edema Edema Edema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema and entrapment of intraocular structures.
• MRI:
  • Determines the extent of soft tissue injury 
  • Assesses damage to the vessels

Management and Complications

Orbital fractures are facial injuries and should be managed emergently. Delay in diagnosis may lead to complications or postoperative complications.

Management

Supportive management:

• Stabilize airway.
• Ensure hemodynamic stability.
• IV fluids
• Pain and nausea medications
• Elevate head. 
• Evaluate for:
  • Cervical spine integrity
  • Possible head injuries 
  • Soft tissue and bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Structure of Bones injuries in the head and neck

Empiric management:

• Antibiotics to cover sinus pathogens
• Advise the patient not to blow the nose Nose The nose is the human body's primary organ of smell and functions as part of the upper respiratory system. The nose may be best known for inhaling oxygen and exhaling carbon dioxide, but it also contributes to other important functions, such as tasting. The anatomy of the nose can be divided into the external nose and the nasal cavity. Anatomy of the Nose, in order to avoid air in the orbital cavity. 
• Reduce periorbital edema Edema Edema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema:
  • Cold compresses 
  • Oral steroids

Urgent ophthalmology consult if:

• Evidence of globe injury: seen in 30% of orbital fractures
• Decreased visual acuity
• Widened intercanthal distance
• Evidence of orbital compartment syndrome Compartment Syndrome Compartment syndrome is a surgical emergency usually occurring secondary to trauma. The condition is marked by increased pressure within a compartment that compromises the circulation and function of the tissues within that space. Compartment Syndrome: 
  • Decreased retropulsion
  • “Rock hard” eyelids
• Open globe
• Severe vagal symptoms

Surgery to reduce the fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures and prevent future deformities:

• May be deferred up to 14 days if periorbital edema Edema Edema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema interferes with visualization and assessment
• Is advised for patients with:
  • Orbital hematoma
  • CSF leakage
  • Globe displacement: exophthalmos or proptosis
  • Entrapment of infraorbital structures leading to the oculocardiac reflex

Commonly used implants for reconstruction are:

• Bone autograft:
  • Provides good strength for reconstruction 
  • Commonly used in children < 7 years of age
• Cartilage Cartilage Cartilage is a type of connective tissue derived from embryonic mesenchyme that is responsible for structural support, resilience, and the smoothness of physical actions. Perichondrium (connective tissue membrane surrounding cartilage) compensates for the absence of vasculature in cartilage by providing nutrition and support. Cartilage: 
  • Most biocompatible
  • Undergoes easy resorption 
  • Most commonly used for small fractures
• Alloplast:
  • Titanium mesh: used for large floor defects
  • Porous polyurethane: used for defects with well-defined edges
  • Resorbable sheeting: used in small gaps with well-defined edges

Complications

Complications arising from orbital fractures can be due to the injury itself or to surgery.

Injury-related complications:

• Ruptured globe
• Orbital hematoma
• Optic nerve sheath hematoma
• Retinal detachment Retinal detachment Retinal detachment is the separation of the neurosensory retina from the retinal pigmented epithelium and choroid. Rhegmatogenous retinal detachment, the most common type, stems from a break in the retina, allowing fluid to accumulate in the subretinal space. Retinal Detachment
• Hyphema
• Muscle entrapment
• Orbital compartment syndrome Compartment Syndrome Compartment syndrome is a surgical emergency usually occurring secondary to trauma. The condition is marked by increased pressure within a compartment that compromises the circulation and function of the tissues within that space. Compartment Syndrome

Surgical complications:

• Intraoperative complications: 
  • Globe and optic nerve injury 
  • Inadequate removal of prolapsed tissue
  • Hemorrhage
• Postoperative complications:
  • Permanent vision loss
  • Persistent diplopia
  • Infection
  • Implant extrusion or malposition