Calcaneal Fracture Classification and Treatment: A Complete Guide for Orthopedic Surgeons

Calcaneal Fracture: Quick Answer

A calcaneal fracture is the most common tarsal bone fracture and often results from high-energy axial loading injuries. Classification systems such as Essex-Lopresti and Sanders are widely used to evaluate fracture patterns and guide treatment decisions. Non-displaced fractures can often be managed conservatively, while displaced intra-articular fractures usually require surgical fixation to restore subtalar joint congruity, calcaneal height, width, and alignment.

What Is a Calcaneal Fracture?

A calcaneal fracture is a break in the calcaneus, the largest tarsal bone in the human body. Because the calcaneus bears substantial body weight and forms both the subtalar and calcaneocuboid joints, fractures can significantly affect foot function and long-term mobility.

Calcaneal fractures are associated with:

• High disability rates

• Chronic pain

• Subtalar arthritis

• Malunion

• Gait abnormalities

• Reduced quality of life

Calcaneal Anatomy Relevant to Fracture Management

Understanding calcaneal anatomy is essential for successful treatment.

Key Anatomical Features

• Largest tarsal bone in the foot

• Forms joints with the talus and cuboid

• Supports body weight transmission

• Functions as the lever arm for the Achilles tendon

• Forms the lateral column of the foot

Subtalar Joint Motion

Normal subtalar motion includes:

The posterior facet is the largest subtalar articular surface and is frequently involved in intra-articular fractures.

Böhler Angle and Gissane Angle

What Is the Böhler Angle?

25∘≤Bohler Angle≤40∘25^\circ \leq Bohler\ Angle \leq 40^\circ25∘≤Bohler Angle≤40∘

The Böhler angle is measured on a lateral radiograph of the calcaneus.

Normal Range: 25°–40°

Clinical Significance

A reduced Böhler angle usually indicates:

• Posterior facet depression

• Loss of calcaneal height

• Severe fracture collapse

A Böhler angle below 25° strongly suggests a displaced calcaneal fracture.

What Is the Gissane Angle?

120∘≤Gissane Angle≤145∘120^\circ \leq Gissane\ Angle \leq 145^\circ120∘≤Gissane Angle≤145∘

The Gissane angle is formed by the intersection of the posterior facet and the anterior process on a lateral X-ray.

Normal Range: 120°–145°

Clinical Significance

Abnormal Gissane angles may indicate:

• Posterior facet disruption

• Articular incongruity

• Calcaneal deformity

• Increased risk of post-traumatic arthritis

Imaging Evaluation of Calcaneal Fractures

Standard Radiographs

Anterior & Lateral View

Evaluates:

• Böhler angle

• Gissane angle

• Calcaneal height

• Calcaneal length

• Posterior facet depression

Harris Axial View

Evaluates:

• Hindfoot alignment

• Calcaneal width

• Sustentaculum tali

• Medial wall comminution

Broden View

Evaluates:

• Posterior subtalar joint surface

Computed Tomography (CT)

CT scanning is the gold standard for surgical planning.

It provides detailed assessment of:

• Posterior facet involvement

• Sustentaculum tali

• Calcaneocuboid joint

• Lateral wall blowout

• Fracture comminution

CT imaging is essential for Sanders classification.

Calcaneal Fracture Classification

Extra-Articular Calcaneal Fractures

Extra-articular fractures do not involve the posterior subtalar facet.

Calcaneal Tuberosity Fractures

Type I

Sleeve avulsion fracture

Type II

Beak fracture

Type III

Infrabursal fracture

Sustentaculum Tali Fractures

Type I

Non-displaced fracture

Type II

Displaced avulsion fracture

Type III

Large fragment involving the calcaneocuboid joint

1a: Beak-like fracture, non-displaced
1c: Beak-like fracture, displaced
1b: Avulsion fracture at the attachment of the Achilles tendon
2a, 2b: Fractures of the medial and lateral processes of the calcaneus
3: Fracture of the sustentaculum tali
4a: Vertical fracture of the calcaneal tuberosity
4b: Apophyseal avulsion fracture
5a: Anterosuperior avulsion or compression fracture
5b: Calcaneocuboid joint fracture
5c: Distal inferolateral fracture
6a: Avulsion fracture of the extensor digitorum tendon
6b: Avulsion fracture of the plantar fascia
6c: Avulsion fracture of the posterior joint capsule

Essex-Lopresti Classification

The Essex-Lopresti classification is based on lateral radiographic findings and remains one of the most widely used systems for describing intra-articular calcaneal fractures.

Tongue-Type Fracture

Characteristics:

• Secondary fracture line extends posteriorly

• Fragment includes posterior facet and tuberosity

• Risk of skin compromise due to fragment displacement

Typical Features

• Posterior superior displacement

• Achilles tendon pull

• Urgent reduction may be necessary

Joint Depression Fracture

Characteristics:

• Secondary fracture line exits superiorly

• Posterior facet collapses into the calcaneal body

• Most common fracture pattern

A-C joint collapse ， D-F tongue-type fracture

Sanders Classification

The Sanders classification is CT-based and is considered the gold standard for evaluating intra-articular calcaneal fractures.

Type I

• Non-displaced fracture

• Articular displacement < 2 mm

Recommended Treatment

Conservative management

Type II

• Two-part posterior facet fracture

• Displacement ≥ 2 mm

Subtypes:

• IIA

• IIB

• IIC

Recommended Treatment

Open reduction and internal fixation (ORIF)

Type III

• Three-part fracture

• Central depressed fragment

Subtypes:

• IIIAB

• IIIAC

• IIIBC

Recommended Treatment

ORIF

Type IV

• Highly comminuted fracture

• Four or more articular fragments

Recommended Treatment

ORIF or primary subtalar fusion in selected patients

Conservative Treatment

Indications

Conservative treatment is appropriate for:

• Most extra-articular fractures

• Sanders Type I fractures

• Articular displacement less than 2 mm

• Patients with severe medical comorbidities

• Poor surgical candidates

Treatment Protocol

• Rest

• Ice

• Compression

• Elevation (RICE)

• NSAIDs

• Splint immobilization

• Non-weight bearing

Surgical Treatment

Indications for Surgery

Surgery is generally recommended for:

• Sanders Type II fractures

• Sanders Type III fractures

• Articular displacement > 2 mm

• Significant loss of calcaneal height

• Hindfoot malalignment

Timing of Surgery

Surgery is usually delayed until soft tissue swelling subsides.

Optimal Timing

• Approximately 5–10 days after injury

• Presence of the "wrinkle sign" indicates readiness

Surgical Techniques

Percutaneous Reduction and Pinning

Advantages:

• Minimally invasive

• Reduced wound complications

• Suitable for selected fracture patterns

Goals:

• Restore Böhler angle

• Restore calcaneal width

• Restore subtalar congruity

Limited Open Reduction and Internal Fixation

Best suited for:

• Sanders Type II fractures

• Joint depression fractures

Advantages:

• Less soft tissue disruption

• Lower infection rates

The lateral wall bone fragment is lifted, and the collapsed articular surface is elevated and reduced. A large bone defect area is visible. The compressed bone of the calcaneal tuberosity is elevated and loosely packed into the bone defect area to avoid a large cavity.

After reduction and bone grafting were completed, the precontoured anatomic locking plate was implanted. Under fluoroscopy, the long wing of the plate was positioned beneath the posterior talocalcaneal articular surface. Two cancellous bone screws were inserted to secure the plate against the calcaneus, one of which was directed into the sustentaculum tali. The locking screws were then inserted sequentially. A small drainage tube was placed in the incision. The subcutaneous tissue was closed in layers, followed by skin closure.

Postoperative X-ray showed good reduction of the posterior talocalcaneal articular surface. At 3 months postoperatively, fracture healing was achieved, and the patient was able to bear full weight. At 1 year postoperatively, the patient walked normally, the internal fixation was removed, and the calcaneus demonstrated normal morphology.

Open Reduction and Internal Fixation (ORIF)

Extensile Lateral Approach

Indications:

• Sanders II fractures

• Sanders III fractures

Objectives:

• Restore articular congruity

• Restore calcaneal height

• Restore calcaneal width

• Restore hindfoot alignment

Is Bone Grafting Necessary?

Routine bone grafting is not required in most calcaneal fractures.

Bone grafting may be considered when:

• Bone defects exceed 2 cm³

• Significant metaphyseal void remains

• Additional subchondral support is needed

Postoperative Rehabilitation

Early Phase

• Limb elevation

• Ice therapy

• Edema control

• Range-of-motion exercises

Weight-Bearing Protocol

Frequently Asked Questions (FAQ)

What is the most commonly used classification for calcaneal fractures?

The Sanders classification is currently the most widely used system because it is CT-based and correlates with treatment decisions and prognosis.

Which calcaneal fractures require surgery?

Displaced intra-articular fractures with more than 2 mm of articular displacement generally require surgical fixation.

What is the normal Böhler angle?

The normal Böhler angle ranges from 25° to 40°.

What is the difference between tongue-type and joint depression fractures?

Tongue-type fractures involve a posteriorly displaced tuberosity fragment, while joint depression fractures primarily involve collapse of the posterior subtalar facet.

Conclusion

Calcaneal fractures remain among the most challenging injuries in foot and ankle trauma. Successful treatment requires a thorough understanding of calcaneal anatomy, fracture classification, imaging evaluation, and surgical indications. Sanders classification remains the most valuable system for operative decision-making, while restoration of subtalar joint congruity, calcaneal height, width, and alignment remains the cornerstone of modern calcaneal fracture management.