March 2014 Small animal case

March 2014

Cat Male castrated

Unknown age

Found lame probably after jumpying from the balcony.

Crepitation and open wound on the right tarsus were present at the clinical examination.

Radiographs of the right tarsus were taken.

Radiographic examination

Mediolateral ( ML, left image) and dorsopalmar ( DP, right image) of the right tarsus.

Radiographic findings

  • There are multiple lucent lines across the calcaneus and the talus. The tuber calcanei is dislocated cranially and a big lateroplantar fragment is visible (arrow).
  • The lateral part of the distal talus is mildly dislocated laterally with the fracture involving the proximal intertarsal joint (arrowhead).
  • Gas inclusions in the soft tissues palmar.
  • The diagnosis was: Open multiple fractures of the right tarsus with mild dislocation, articular involvement of the proximal intertarsal joint and instability.
  • The cat underwent open reduction and internal fixation.
  • Post OP radiographs are shown.

Radiographic findings

Close up of the DP view of the right tarsus.

Radiographic examination

ML (on the left) and DP (on the right) post OP radiographs of the right tarsus.

Comments

  • The cat was radiographed 7 weeks post OP. The 2 pins in the tuber calcanei were removed, as well as the bony fragment wich evolved in a sequestrum (images not shown).
  • 3 weeks later (10 weeks post OP) the cat was radiographed again because at the clinical examination the skin defect was still partially open and he was painful.

Radiographic examination

ML (on the left) and DP (on the right)10 weeks post OP radiographs of the right tarsus

Comments

  • There is progressive soft tissue swelling mainly plantar with skin defect in the area of the proximal plate.
  • The plate is dislocated plantar, there are multiple area of lysis around the first 3 proximal screws.
  • There is progressive dorsal angulation of the proximal tuber calcanei and malalignment of the distal part of the talus.
  • The tibiotarsal joint is widened laterally, the fracture gaps still well visible with no sign of callus formation.
  • The radiographic diagnosis was implant failure with osteomyelitis and instability of the tibiotarsal and proximal intertarsal joint right. Progressive surrounding soft tissue swelling as cellulitis.
  • The plate was removed, bacteriology samples were taken and revealed multiresistant Staphiloccus aureus pseudointermedium, E.coli and Proteus.
  • Antibiotic therapy was started, the cat was sent home with a splint.
  • 3 weeks later at the clinical examination, the skin was closed, the calcaneus was more stable and the tarsus could be flexed up to 135°.
  • One month later (almost 5 months post trauma) the tarsus was radiographed again.

Close up of the DP (on the left ) and ML view of the right tarsus. There is progressive osteomyelitis, osteoarthritis, severe malaligment of the calcaneus and talus, instability and luxation of the tibiotarsal and proximal intertarsal joints.Non union of the fracture fragments.