Calcaneus (Os Calcis) Fractures

Mechanism

• Calcaneus initially fractures into two main fragments
• fracture line runs plantarmedial to dorsolateral
• results in two main fragments
  • anteromedial(sustentacular fragment)
    • rarely comminuted
    • variable size
    • remains attached to the talus by the strong deltoid & interosseous talocalcanean ligaments
  • dorsolateral (tuberosity fragment)
    • Comminution of this fragment is common
    • displaces superiorly & laterally
    • resulting in incongruity of the posterior facet & widening & shortening of the heel

Classifications

Essex-Lopresti

• according to the direction of the “secondary fracture line”
• Tongue fracture
  • secondary fracture line
    • runs straight back to the posterior border of the tuberosity from the crucial angle (of Gissane)
  • This produces one large posterior, superior & lateral fragment
  • It can be displaced, “like a see-saw, down at the front & up at the back”
  • displaced key fragment can be maneuvered using the long lever
  • fragment may be flexed by the continuing pull of the Achilles tendon
• Joint depression fracture
  • secondary fracture line
    • runs across the body just behind the joint, & deviates dorsally to exit the bone just posterior to the articular facet, creating a fragment separate to the tuberosity – the thalamic portion
      • which contains the major portion of the posterior articular facet of the calcaneus
  • This also acts in a see-saw fashion, down at the front & up at the back
  • More common than the tongue fracture
  • displaced fragment buried in the bone can only be reduced by an open approach

Sanders CT based Classification

• based on coronal & axial CT scans
  • widest undersurface of the posterior facet of the talus is divided into 3 by two lines, A & B
  • A third line, C, corresponds to the medial edge of the posterior facet of the talus, & separates the posterior facet from the sustentaculum
  • These lines result in a total of four potential pieces
  • order A, B, C, D is from lateral to medial because the lateral fragments are easiest to reduce from a lateral approach

Type	Description
I	~All non-displaced articular fractures, irrespective of the number of fracture lines
II	~two part fractures of the posterior facet, similar in appearance to a split fracture of the tibial plateau ~Three types, IIA, IIB & IIC exist, based on the location of the primary fracture line
III	~three part fractures that feature a centrally depressed fragment, similar to a die punch type distal radial fracture ~Types include IIIAB, IIIAC & IIIBC
IV	~highly comminuted ~often more than four articular fragments exist

Investigations

Xray

• AP, lateral & axial calcaneal
• Broden’s view
  • X-ray view to demonstrate the posterior facet of the subtalar joint
  • foot is in neutral flexion
  • leg is internally rotated 30°
  • beam is centred over the lateral malleolus
  • Four views are taken with the beam angled 40, 30, 20 & 10° respectively toward the head
  • 10 degree view shows the posterior part of the facet
  • 40 degree view the anterior part of the facet.

CT Scan

• patient is positioned in the supine position with the knees & hips flexed
• feet are kept together with the planter surface resting on the table
• Both feet are routinely scanned for comparison
• Sagittal & coronal section are required, through the posterior subtalar joint

Treatment

Nonoperative treatment

• If nonoperative treatment is selected, ankle & subtalar ROM exercises are crucial to maintain adequate subtalar motion.

Operative treatment

• Options
  • ORIF
  • Percutaneous Fixation
  • Primary Arthrodesis
• Principles
  • Essex-Lopresti
    • Tongue type
      • principle is to insert a Gissane spike (nowadays a Schanz pin) into the long axis of the displaced fragment
      • use this to lever the tongue in its correct alignment with the taloid component of the posterior joint
    • Joint depression
      • fracture is openly reduced by a lateral incision & after reduction is held with a Gissane spike
  • ORIF
    • Surgical Technique for ORIF Calcaneum
  • Primary Arthrodesis
    • option for extremely comminuted (Sanders IV) fractures

Complications

• Compartment syndrome in 10%
• Difficulty in shoe wearing due to heel widening
• Peroneal impingement
• Subtalar arthritis
• Tarsal tunnel syndrome
• Wound problems
  • higher in smokers, diabetics & patients with peripheral vascular disease
• Nonunion
  • is almost unknown, due to the excellent blood supply to the bone