Introduction
The calcaneum is the most commonly fractured tarsal bone. It is most commonly injured following a fall from height, whereby there is significant axial loading directly onto the bone.
As such, this injury is often associated with concurrent fractures (particularly spinal or contralateral calcaneus) or even severe visceral injuries. Around 15% of all calcaneal fractures are open fractures.
Figure 1 – The tarsal bones of the foot, including the calcaneus
Classification
Calcaneal fractures are divided into intra-articular and extra-articular fractures on the basis of subtalar joint involvement.
- Intra-articular – Around 75% of calcaneal fractures
- Involves the articular surface of the subtalar joint, can further be classified by the Sanders Classification (Table 1)
- Extra-articular – Around 25% of calcaneal fractures
- Commonly are avulsion fractures, with sparing of the articular surface of subtalar joint, including avulsion of the calcaneal tuberosity by the Achilles tendon
Management can be guided by this classification (Table 1), as intra-articular fractures will likely require definitive fixation
|
Type I |
Nondisplaced posterior facet (regardless of number of fracture lines) |
|
Type II |
One fracture line in the posterior facet (two fragments) |
|
Type III |
Two fracture lines in the posterior facet (three fragments) |
|
Type IV |
Comminuted with more than three fracture lines in the posterior facet (four or more fragments) |
Table 1 – Sanders Classification of Intra-Articular Calcaneal Fractures
Clinical Features
Patients will typically present following recent trauma*, such as a fall from height or road traffic accident. As such, all patients should be managed as per ATLS guidelines.
If conscious, patients will report pain and tenderness around the calcaneal region, with an inability to weight bear.
On examination, the region will be significantly swollen and bruised, with potential for a shortened and widened heel. They may also have an apparent varus deformity.
It is important to asses for posterior heel skin integrity, as any tenting or blanched skin will warrant emergency surgical intervention.
*Less commonly, calcaneal fractures can present as stress fractures, with pain on activity without any specific history of trauma
Differential Diagnoses
For a patient with a history of trauma and pain and swelling around the calcaneal region, differential diagnoses include a talar fracture, ankle fracture, or soft tissue injury.
Investigations
Initial imaging to diagnose the fracture can be via plain film radiograph, using antero-posterior, lateral, and oblique views (Fig. 2A). Findings in cases of calcaneal fracture include calcaneal shortening, varus tuberosity deformity, or a decreased Böhler’s angle*.
However, CT imaging is the gold standard for assessing calcaneal fractures (Fig. 2B), and should be performed in any suspected case.
*Böhler’s angle is the posterior angle formed between one line from the anterior to middle facet, and one line from the posterior to middle facet; this is normally 20-40o, however a reduced Böhler’s angle can indicate a calcaneal fracture
Figure 2 – (A) Plain Film Lateral View Radiograph showing an Extra-Articular fracture of the Calcaneus (B) CT Imaging showing a Comminuted Intra-Articular Calcaneal Fracture
Management
The majority of intra-articular calcaneal fractures will require surgical intervention, however those with <2 mm displacement or near normal Böhler’s angle, may be considered for conservative treatment.
Certain extra-articular fractures will be treated non-operatively, unless there is significant displacement, with cast immobilisation and non-weight bearing for 10-12 weeks.
Surgical Intervention
Closed reduction with percutaneous pinning can be attempted for large (>1cm) but minimally displaced fractures
However, an open reduction internal fixation (ORIF) is usually required for most calcaneal fractures warranting surgical intervention, especially for open fractures, posterior facet displacement, a reduced Böhler’s angle, or any calcaneocuboid joint involvement.
Any fracture with skin compromise warrants emergency surgical fixation, before any skin breakdown occurs.
Complications
The main complication of a calcaneal fracture is subtalar arthritis, therefore optimal management in the acute setting is key.
Conservative management of subtalar arthritis is with analgesia and physiotherapy, however if this is unsuccessful, subtalar arthrodesis may be required.
Key Points
- The calcaneum is the most commonly fractured tarsal bone
- Patients will typically present following recent trauma, such as a fall from height or road traffic accident, therefore concurrent injuries are common
- CT imaging is the gold standard for assessing calcaneal fractures
- Open reduction internal fixation is usually required for most calcaneal fractures warranting surgical intervention