1. Overview
Fractures of the talus are relatively uncommon injuries, accounting for approximately 3–6% of all foot fractures and 2–7% of all foot injuries. Despite their low incidence, talar fractures are of major clinical importance due to the talus’s central role in the biomechanics of the:
● ankle joint
● subtalar joint
● transverse tarsal joint
Injury to the talus can result in significant impairment of hindfoot motion, load transmission, and long-term functional outcomes.
The talus is unique among tarsal bones because:
● it has no muscular or tendinous attachments,
● nearly three-fifths of its surface is covered with articular cartilage,
● it has a limited and precarious vascular supply.
These features explain the high incidence of complications such as:
● osteonecrosis,
● malunion,
● nonunion,
● posttraumatic arthritis.
Despite advances in imaging and fixation techniques, talus fractures remain among the most challenging injuries in orthopedic trauma.
2. Anatomy and Biomechanical Considerations
2.1 Anatomical Components of the Talus
The talus consists of four main parts:
● head
● neck
● body
● posterior process
Key anatomic features:
● The talar neck is the narrowest region and has a thin cortex → most vulnerable to fracture.
● The posterior process contributes ~25% of the subtalar joint surface.
● The trochlear surfaces and lateral process form the talar component of the ankle joint.
2.2 Stability and Joint Relationships
Stability of the talus is provided by:
● bony constraints of the medial and lateral malleoli,
● strong surrounding ligamentous structures.
Fracture or dislocation may disrupt:
● joint congruity,
● vascular integrity,
leading to poor outcomes.
3. Mechanisms of Injury
Talus fractures occur via a spectrum of mechanisms, from low-energy rotational forces to high-energy axial loading.
3.1 High-Energy Mechanisms
Common causes:
● motor vehicle collisions,
● falls from height.
Typical mechanism:
● axial load applied to the foot
● ankle held in dorsiflexion
→ distal tibia impacts the talar neck.
Most commonly associated fractures:
● talar neck fractures,
● talar body fractures.
3.2 Low-Energy Mechanisms
Usually involve the talar processes and occur due to:
● inversion,
● eversion,
● rotational forces.
Specific patterns:
● Lateral process fractures (“snowboarder’s fracture”):
axial loading of a dorsiflexed ankle + eversion or external rotation.
● Posterior process fractures:
extreme plantarflexion with axial compression or ligamentous avulsion.
3.3 Talar Head Fractures
● Rare injuries.
● Result from shear forces across the talonavicular joint during inversion or eversion.
● May occur:
○ in isolation, or
○ in combination with talar neck fractures.
4. Epidemiology and Associated Injuries
Talus fractures:
● occur more commonly in young adults,
● are more frequent in males.
Because they are often caused by high-energy trauma, they are frequently associated with:
● polytrauma,
● ipsilateral fractures of:
○ ankle and foot,
○ calcaneus,
○ tibial plafond,
○ medial and lateral malleoli.
A high incidence of associated injuries mandates a systematic ATLS-based trauma evaluation.
Approximately 20–25% of talar neck fractures are open fractures, requiring emergent management due to:
● infection risk,
● soft-tissue compromise.
5. Clinical Presentation and Examination
5.1 Symptoms
Typical presentation includes:
● pain,
● swelling,
● restricted ankle or hindfoot motion.
High-energy injuries:
● obvious deformity.
Low-energy injuries (especially process fractures):
● subtle findings,
● high risk of missed diagnosis.
5.2 Physical Examination
Essential components:
● inspection of the soft-tissue envelope,
● assessment for:
○ open wounds,
○ skin compromise,
○ neurovascular injury.
Important consideration:
● Posteromedial displacement of the talar body may compress the posterior tibial neurovascular bundle → urgent reduction required.
A detailed neurologic and vascular examination must be documented.
Abnormal findings warrant further vascular evaluation.
6. Imaging Evaluation
6.1 Plain Radiography (Initial Imaging)
Standard ankle radiographs include:
● anteroposterior (AP),
● mortise,
● lateral views.
Special view:
● Canale oblique view
→ improves visualization of talar neck alignment and shortening.
6.2 Computed Tomography (CT)
CT is essential for:
● precise fracture localization,
● assessment of displacement,
● comminution,
● articular surface involvement.
CT is critical for:
● preoperative planning,
● identification of intra-articular fragments,
● detection of subtle joint incongruities.
6.3 Magnetic Resonance Imaging (MRI)
Limited role acutely.
Useful when:
● radiographs and CT are inconclusive,
● occult fractures or stress injuries are suspected,
● associated soft-tissue pathology needs evaluation.
7. Classification of Talar Fractures
7.1 Hawkins Classification (Talar Neck Fractures)
Most widely used classification system; correlates displacement with risk of vascular compromise.
● Type I: nondisplaced fracture, no joint subluxation
● Type II: displaced fracture with subtalar subluxation or dislocation
● Type III: displaced fracture with ankle and subtalar dislocation
● Type IV: fracture with dislocation of ankle, subtalar, and talonavicular joints
Modifications further subdivide Type II fractures based on subtalar joint subluxation versus dislocation, reflecting differences in osteonecrosis risk.
7.2 OTA Classification
The Orthopaedic Trauma Association (OTA) classification:
● includes fractures of the talar head, neck, body, and processes,
● allows standardized injury description,
● facilitates research comparison.
8. Vascular Supply and Osteonecrosis
The talus has a tenuous blood supply derived from:
● posterior tibial artery,
● anterior tibial artery (dorsalis pedis),
● peroneal artery.
Key vascular structures:
● arteries of the tarsal canal,
● arteries of the tarsal sinus,
● deltoid ligament branches.
Disruption of this network—especially in displaced talar neck fractures—places the talus at high risk for osteonecrosis.
Risk increases with:
● fracture displacement,
● comminution,
● associated joint dislocations.
9. Management Principles
9.1 Emergency Care and Timing
● Urgent reduction of displaced fractures/dislocations is mandatory to:
○ relieve soft-tissue tension,
○ prevent neurovascular compromise.
Although historically treated as surgical emergencies, surgical timing alone does not predict osteonecrosis.
Poor outcomes correlate more strongly with:
● fracture severity,
● comminution,
● open injuries.
9.2 Surgical Treatment
Operative fixation is generally indicated for:
● displaced talar neck fractures,
● displaced talar body fractures.
Primary goals:
● anatomic reduction of the talar neck,
● restoration of joint congruity.
Common approaches:
● dual anteromedial and anterolateral approaches.
Fixation methods:
● multiple screws,
● plates in comminuted fractures to maintain length and alignment.
9.3 Postoperative Care
● Early controlled motion once soft tissues permit.
● Strict limitation of weight-bearing until radiographic healing is evident.
● Long-term follow-up is essential to monitor for:
○ osteonecrosis,
○ posttraumatic arthritis.