CORE EM: Calcaneus Fractures

Definition: Fracture of the calcaneus bone

Mechanism

• Traumatic axial loading is the most common cause (eg fall from height)
• Can also occur in MVCs when the accelerator/brake pedal impacts the foot
• Stress fractures seen with overuse from repetitive impact (e.g. runners)

Epidemiology

• 2% of all fractures
• Most frequently fractured tarsal bone
• 90% occur in men between 21 and 45 years of age with majority being industrial workers
• Approximately 10% are open fractures (Egol 2010)

The Calcaneus (joint-pain-expert.net/calcaneus)

Ecchymosis after Calcaneus Fracture (orthopaedicsone.com)

Physical Exam

• Moderate to severe heel tenderness
• Swelling
• Shortened wide heel with varus deformity
• Ecchymosis around heel extending to arch is highly suggestive, may also see fracture blisters
• Compartment syndrome occurs in 10% of calcaneal fractures and can result in clawing of the toes after recovery (Egol 2010)
• Concomitant Achilles tendon rupture may be present

Calcaneus Fracture Classification (See Images in Gallery Below)

• Extra-articular (subtalar joint)
  • 25% of all calcaneus fractures
  • Avulsion injury of:
    • Anterior process by bifurcate ligament
    • Sustenaculum tali
    • Calcaneal tuberosity (Achilles tendon avulsion)
• Intra-articular
  • 75% of calcaneus fractures
  • 2 classification systems
    • Essex-Lopresti Classification
      • The primary fracture line runs obliquely through the posterior facet forming two fragments.
      • The secondary fracture line runs in one of two planes:
        • “Tongue-Type” Fracture
          • Axial plane beneath the posterior facet exiting posteriorly
          • This fracture tends to cause tension on the skin with possible necrosis. Consider an emergent orthopedics consult for all patients with this pattern (Snoap 2017)
        • Behind the posterior facet in joint depression fractures
    • Sanders (based on CT)- based on number and location of articular fragments seen on the coronal CT image at the widest point of the posterior facet (E)
      • Type I: all nondisplaced fractures
      • Type II: two-part fractures of the posterior facet
      • Type II: three-part fractures with centrally-depressed fragment
      • Type IV: four-part articular fractures

Sanders Classification (foothyperbook.com)

Bohler Angle (orthobullets.com)

Diagnostic Imaging

• Standard X-rays: AP, lateral, oblique foot
• Optional X-rays (See Image Gallery below)
  • Broden views: allows visualization of posterior facet
  • Harris View: visualizes tuberosity fragment widening, shortening, and varus positioning
  • AP ankle: demonstrates fibular impingement if lateral wall extrusion is present
• Findings in calcaneal fractures:
• Reduced Bohler angle
  • Created with lines drawn tangiental to anterior and posterior aspects of superior calcaneus
  • Normal is 20-40 degrees
• Increased angle of Gissane
  • Formed by downward and upward slopes of calcaneus
  • Normal is 95-105 degrees
• Non-contrast CT
  • Obtain when clinical suspicion of a fracture is high despite negative x-rays
  • Gold standard imaging test for any calcaneal fracture (except for stress fractures)
  • Will almost always be obtained for pre-operative planning but does not necessarily need to be obtained in the ED

Angle of Gissane (orthobullets.com)

Associated Injuries

• Vertebral injuries secondary to axial loading injury (10%)
• Contralateral calcaneal injury (10%) (Hatch)

ED Management

• Provide analgesia
• Complete neurovascular exam
• Consider compartment syndrome
• Can initially be placed in Bulky Jones dressing with supportive posterior splint to provide flexion
• Conservative therapy (casting + nonweightbearing)
  • Casting and nonweightbearing for 6 weeks for calcaneal stress fractures
  • Casting and nonweightbearing for 10-12 weeks if:
    • Small extra-articular fracture (<1 cm) with intact Achilles tendon and <2 mm displacement
    • Sanders Type I (nondisplaced)
    • Anterior process fracture involving <25% of calcaneocuboid joint
    • Comorbidities that preclude good surgical outcome (smoker, diabetes, PVD)
• All other fractures require surgical intervention

Prognosis: Relatively poor with overall 40% complication rate (malunion, subtalar arthritis, clawing of toes)

Take Home Points

• Always suspect calcaneus fractures in patients with axial loading injuries to the lower extremities. If a calcaneus injury is found, look for concomitant fractures of the ankle and vertebrae.
• Patients with calcaneal fractures will always be nonweightbearing on ED discharge
• Watch out for compartment syndrome of the foot which occurs in 10% of calcaneal fractures and results in significant morbidity

Read More

Ortho Bullets: Calcaneus Fractures

References

• Barrie J. (2013) Calcaneal fractures. [East Lancashire Foot and Ankle Hyperbook]. Link
• Egol KA et al. Handbook of Fractures 4^th ed. Lipincott 2010: 507-519.
• Gitajn IL et al. Anatomic alignment and integrity of the sustenaculum tali in intra-articular calcaneal fractures. J Bone Joint Surg Am. 2014; 96(12): 1000-1005. PMID: 24951735.
• Snoap T et al. Calcaneal Fractures: A Possible Musculoskeletal Emergency. J Emerg Med 2017.52 (1), 28-33 PMID: 27658550