Introduction

• The talocalcaneal joint is a synovial diathrodial structure with 3 cartilage covered articular facets and a proximal and distal ligament between the 2 bones. There are no ligamentous structures directly connecting the external surfaces of the 2 bones.
• Disruption of the ligaments between the talus and calcaneus results in luxation of the 2 bones and subluxation at the calcaneoquartal or talocentral joint.
• Talocalcaneal luxation does not occur in isolation - it is important to include the relative direction of movement of the talar head or distal calcaneus.
• Uncommon injury in dogs, more frequent in cats.
• Cause: blunt trauma.
• Signs: non-weight-bearing hindlimb lameness and hock deformity.
• Treatment: internal fixation.
• Prognosis: good.

Pathogenesis

Etiology

• Blunt trauma.

Pathophysiology

• Rupture of the talocalcaneal ligaments can result in 4 different outcomes:
  • Dorsal displacement of talar head with talocentral luxation (most common).
  • Plantar displacement of talar head with talocentral luxation.
  • Plantar displacement of distal calcaneus with calcaneoquartal subluxation.
  • Dorsal displacement of distal calcaneus with calcaneoquartal subluxation (unreported).
• There may be concurrent collateral ligament rupture Tarsus: collateral ligament rupture or fractures of the talus.
• In all cases defect infills with fibrous tissue (if chronic luxations) → reduction difficult.

Diagnosis

Treatment

Outcomes