title: Femoral angular correction and lengthening in a large-breed puppy using a dynamic unilateral external fixator.
abstract: OBJECTIVE
  To report treatment of a large-breed puppy with combined distal femoral valgus and length deficit caused by partial distal physeal closure.
  
  
  METHODS
  Clinical report.
  
  
  METHODS
  Bernese Mountain Dog (4.5-month-old male).
  
  
  METHODS
  The puppy was admitted for evaluation of a progressive severe left pelvic limb lameness (grade 3/4) of 6-week duration. Distal femoral valgus and severe length deficit deformity were treated by acute angular correction using a closing wedge ostectomy and progressive rapid-rate callus distraction using a dynamic, telescoping unilateral External Skeletal Fixator (ESF) designed for people. After acute angular correction and a 3-day latency period, a mean linear distraction rate of 3 mm/day was maintained for 3 weeks. The dynamic ESF (dESF) was removed at 4 weeks, after a 1-week consolidation phase.
  
  
  RESULTS
  The dESF was stable and functional during distraction and bone healing. Distal femoral valgus conformation improved 50° (from 41° to 91°) and femoral length increased 42 mm at dESF removal (from 158 mm to 200 mm; 27%). After cessation of bone growth, no valgus and minimal (6%) length deficit were detected. At 4, 5, 6, 12, and 24 months after surgery, the dog was walking, trotting, and galloping normally.
  
  
  CONCLUSIONS
  Acute angular correction and progressive rapid-rate callus distraction using a unilateral dESF allowed satisfactory treatment of combined distal femoral valgus and length deficit in a large-breed puppy.
authors.affiliation: Clinica Veterinaria Milano Sud, Peschiera Borromeo, Milano, Italy. massimo.petazzoni@cvmilanosud.it
authors.forename: Massimo
authors.initials: M
authors.lastname: Petazzoni
authors.forename: Ross H
authors.initials: RH
authors.lastname: Palmer
mesh_terms: D000818:Animals; D004283:Dog Diseases / Q000473:pathology / Q000601:surgery*; D004285:Dogs; D016267:External Fixators / Q000662:veterinary*; D005269:Femur / Q000002:abnormalities / Q000601:surgery*; D006614:Hindlimb / Q000002:abnormalities* / Q000601:surgery; D007870:Leg Length Inequality / Q000601:surgery / Q000662:veterinary*; D008297:Male; D019857:Osteogenesis, Distraction / Q000379:methods / Q000662:veterinary*; D016896:Treatment Outcome