title: Surgical correction of bilateral metacarpophalangeal valgus with curved osteotomies and type II external skeletal fixation in a seven-month-old alpaca.
abstract: OBJECTIVE
  To report the successful surgical correction of severe bilateral metacarpophalangeal valgus angular limb deformities in a seven-month-old intact male alpaca cria using curved osteotomies stabilized with type II external skeletal fixation.
  
  
  METHODS
  Using a 21 mm crescentic shaped oscillating saw blade, bilateral osteotomies were performed in the distal metaphyses of the fused third and fourth metacarpal bones to correct valgus angular limb deformity of the metacarpophalangeal joints. Axial alignment of each limb was achieved by medially rotating the distal metacarpus in the frontal plane along the curved osteotomies. The osteotomies were stabilized using type II external skeletal fixators.
  
  
  RESULTS
  The alpaca was immediately weight-bearing following the surgical procedure and no to minimal lameness was observed during healing of the osteotomies. Evaluation at five and 10 months following the surgery demonstrated acceptable axial alignment in the left forelimb while moderate to severe varus deformity (overcorrection) was observed in the right.
  
  
  CONCLUSIONS
  Curved osteotomy of the distal metacarpus stabilized with type II external skeletal fixation can provide a favourable outcome in older alpaca crias affected with metacarpophalangeal angular limb deformities. Placement of the distal transfixation pins relative to the metacarpal physes should be carefully evaluated as overcorrection is possible, especially if growthpotential remains in only one physis of the fused third and fourth metacarpal bones.
authors.affiliation: Mike J. Schoonover, DVM, MS, Diplomate ACVS-LA, Diplomate ACVSMR, Department of Veterinary Clinical Sciences, Center for Veterinary Health Sciences, Oklahoma State University, 001 BVMTH, Stillwater, OK 74078-1010, United States, E-mail: mjsdvm@gmail.com.
authors.forename: Mike J
authors.initials: MJ
authors.lastname: Schoonover
authors.forename: Chase T
authors.initials: CT
authors.lastname: Whitfield
authors.forename: Mark C
authors.initials: MC
authors.lastname: Rochat
authors.forename: Robert N
authors.initials: RN
authors.lastname: Streeter
authors.forename: Kate
authors.initials: K
authors.lastname: Sippel
mesh_terms: D000818:Animals; D002161:Camelids, New World / Q000002:abnormalities / Q000601:surgery*; D016267:External Fixators / Q000662:veterinary; D007596:Joints / Q000002:abnormalities* / Q000000981:diagnostic imaging / Q000601:surgery; D008297:Male; D050279:Metacarpal Bones / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000601:surgery*; D010027:Osteotomy / Q000295:instrumentation / Q000379:methods / Q000662:veterinary*; D011859:Radiography / Q000662:veterinary; D050277:Toe Phalanges / Q000002:abnormalities* / Q000000981:diagnostic imaging / Q000601:surgery
keywords: Angular limb deformities; alpaca; external skeletal fixation; osteotomy