title: Surgical induction, histological evaluation, and MRI identification of cartilage necrosis in the distal femur in goats to model early lesions of osteochondrosis.
abstract: OBJECTIVE
  Identify and interrupt the vascular supply to portions of the distal femoral articular-epiphyseal cartilage complex (AECC) in goat kids to induce cartilage necrosis, characteristic of early lesions of osteochondrosis (OC); then utilize magnetic resonance imaging (MRI) to identify necrotic areas of cartilage.
  
  
  METHODS
  Distal femora were perfused and cleared in goat kids of various ages to visualize the vascular supply to the distal femoral AECC. Vessels located on the axial aspect of the medial femoral condyle (MFC) and on the abaxial side of the lateral trochlear ridge were transected in eight 4- to 5-day-old goats to induce cartilage necrosis. Goats were euthanized 1, 2, 3, 4, 5, 6, 9, and 10 weeks post operatively and operated stifles were harvested. Adiabatic T1ρ relaxation time maps of the harvested distal femora were generated using a 9.4 T MR scanner, after which samples were evaluated histologically.
  
  
  RESULTS
  Interruption of the vascular supply to the MFC caused lesions of cartilage necrosis in 6/8 goat kids that were demonstrated histologically. Adiabatic T1ρ relaxation time mapping identified these areas of cartilage necrosis in 5/6 cases. No significant findings were detected after transection of perichondrial vessels supplying the lateral trochlear ridge.
  
  
  CONCLUSIONS
  Cartilage necrosis, characteristic of early OC, can be induced by interrupting the vascular supply to the distal femoral AECC in goat kids. The ability of high field MRI to identify these areas of cartilage necrosis in the AECC using the adiabatic T1ρ sequence suggests that this technique may be useful in the future for the early diagnosis of OC.
authors.affiliation: Veterinary Population Medicine Department, University of Minnesota, St. Paul, MN, USA. Electronic address: ftoth@umn.edu.
authors.forename: F
authors.initials: F
authors.lastname: Tóth
authors.affiliation: Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, 2021 Sixth Street SE, Minneapolis, MN 55455, United States; Department of Orthopaedic Surgery, University of Minnesota, Minneapolis, MN, USA. Electronic address: nissi@cmrr.umn.edu.
authors.forename: M J
authors.initials: MJ
authors.lastname: Nissi
authors.affiliation: Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, 2021 Sixth Street SE, Minneapolis, MN 55455, United States. Electronic address: lnwang1222@gmail.com.
authors.forename: L
authors.initials: L
authors.lastname: Wang
authors.affiliation: Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota, 2021 Sixth Street SE, Minneapolis, MN 55455, United States. Electronic address: eller001@umn.edu.
authors.forename: J M
authors.initials: JM
authors.lastname: Ellermann
authors.affiliation: Veterinary Population Medicine Department, University of Minnesota, St. Paul, MN, USA. Electronic address: carls099@umn.edu.
authors.forename: C S
authors.initials: CS
authors.lastname: Carlson
mesh_terms: D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D004195:Disease Models, Animal; D005269:Femur; D006041:Goats; D006132:Growth Plate / Q000098:blood supply / Q000473:pathology* / Q000601:surgery; D006801:Humans; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging; D009336:Necrosis; D055034:Osteochondrosis / Q000473:pathology*; D013264:Stifle
keywords: Adiabatic T1ρ; Cartilage necrosis; Goat; MRI; Osteochondrosis