The talocrural (ankle) joint is the junction of three bones: distal ends of tibia and fibular and the talus trochlear

The tibia and fibular are bound by the ligamentous structures that include the syndesmosis, anterior/posterior/transverse tibiofibular ligaments.

Collateral ligaments include the anterior and posterior fibulotalar ligaments, fibulocalcanear on the lateral side while the medial side is supported by the deltoid ligament and calcaneonavicular ligaments.

The ankle joint is not a pure hinge joint as there is some rotation around the helical axis of the joint due to the asymmetrical shape of the talus.

Precise ankle joint congruence is important for load distribution of the compressive forces across the joint.

Medial aspect of left foot

Lateral aspect of left foot

Dorsal view of left foot

Plantar view of left foot

Anterior axial view of right foot blood and nerve supply

The hindfoot consists of the Talus and Calcaneus while the midfoot is formed by a cluster of small bones forming the arch of the foot and they are connected by the metatarsal bones to the toes. Calcaneus fractures are the most common tarsal bone fractures. It is important to appreciate the significant soft tissue injury associated with the fracture component and efficiently mange this.

Normal foot

Injury Mechanism:

Direct axial force during motor vehicle accidents or falling from a height produces an intra-articular fracture
Indirect mechanism with contracture of the triceps surae with a forced foot dorsiflexion produces a tuberosity fracture
Anterior process fracture usually due to a rotational foot injury with inversion of a plantarflexed foot
Calcaneal stress result from repetitive overloading of calcaneus in athletic overtraining .

Causes:

• Twisting/rotational movements during activity especially during sport activities
• Falls from a height
• Motor vehicle accidents

Presentation:

• Pain
• Swelling with bruising
• Deformity
• Inability to walk with pain that worsens with standing or walking

Clinically:

• Bruising along the foot
• Short and widened heel
• Hindfoot/Midfoot bone and joint tenderness
• Assess skin integrity at heel and make sure skin blanches
• Exclude foot compartment syndrome
• Examine pulses and surrounding nerve function

Assess skin integrity as this require urgent surgery if compromised

Variation in calcaneus fractures include tongue-type or depressed type:

The primary fracture line in the calcaneus runs through the posterior facet creating a superolateral fragment and a constant superomedial fragment (including the sustentaculum tali). Greater force can cause a secondary fracture line and depending on the fracture direction, either a tongue type or depressed type of fracture configuration occurs.

Type Ⅰ: Nondisplaced posterior facet (< 2mm displacement)

Type Ⅱ: One fracture line in posterior facet ( 2 fragments)

Type Ⅲ: Two fracture lines in posterior facet (3 fragments)

Type Ⅳ: Comminuted with > 3 fracture lines in the posterior facet

Type Ⅰ: avulsion or sleeve tuberosity fracture

Type Ⅱ: ‘Beak’ type avulsion

Type Ⅲ:  Infra-bursal avulsion from middle third of posterior tuberosity

Investigations:

X-ray:

• Ankle
• Foot: AP, Lateral & oblique. Additional views include Broden views to assess the posterior facet and Harris views to visualize tuberosity fragment widening.

X-ray findings:

• Fracture lines
• Low arch with decreased Bohler’s angle and increased angle of Gissane
• CT: for intra-articular fracture evaluation and surgical planning
• MRI: useful to evaluate calcaneus stress fracture

Nonoperative:

• Stress fracture: cast for 6-8 weeks
• Nondisplaced or minimally displaced (< 2mm articular step) body fractures or minimally displaced tuberosity (< 1cm) fractures. Cast with non-weight bearing for 10-12 weeks
• Small anterior process fracture

Surgery:

Manage soft tissue swelling appropriately before performing surgery

• Displaced body or significantly displaced tuberosity fractures
• Skin compromise with avulsion fracture require urgent surgery intervention

Nonoperative:

• Percutaneous pinning
• Screw fixation
• Plate and screw fixation

Approach: Lateral aspect of Achilles tendon and calcaneal tuberosity tip

Approach:

• Posterior arm is midway between fibular & Achilles tendon
• Horizontal incision in line with 5th metatarsal
• Full thickness flap

• Approach: Lateral aspect of Achilles tendon and calcaneal tuberosity tip
• Reduce fracture
• Screw fixation

Lateral approach:

• Posterior arm is midway between fibular & Achilles tendon. Horizontal incision in line with 5th metatarsal
• Fracture reduction
• Plate & screw fixation

• Non weight bearing in a cast for 8-12 weeks until union.
• Progressive rehabilitation

Foot strengthening exercise routine

Resistance strength exercise routine

1. Avulsion fracture of the calcaneal tuberosity. RC Beavis, K Rouke, C Court-Brown. Foot Ankle Int 2008 29: 863-866.
2. Avulsion fracture of the calcaneal tuberosity: classification and its characteristics. SM Lee, SW Huh, JW Chung, DW Kim, YJ Kim, SK Rhee. Clinics in Orthopedic Surgery 2012;4: 134-138.
3. Classifications in brief: Saunders classification of intraarticular fractures of the calcaneus. JH Jiménez-Almonte, JD King, TD Luo, A Aneja, E Moghadamian. Clin Orthop Relat Res. 2019 Feb;477(2): 467-471.
4. Calcaneus fractures: where are we now? A Razik, M Harris, A Trompeter. Strat Traum Limb Recon (2018) 13: 1-11.