title: A study of acute and chronic tissue changes in surgical and traumatically-induced experimental models of knee joint injury using magnetic resonance imaging and micro-computed tomography.
abstract: The objective of this study was to monitor the progression of joint damage in two animal models of knee joint trauma using two non-invasive, clinically available imaging modalities.
  
  
  
  A 3-T clinical magnet and micro-computed tomography (μCT) was used to document changes immediately following injury (acute) and post-injury (chronic) at time points of 4, 8, or 12 weeks. Joint damage was recorded at dissection and compared to the chronic magnetic resonance imaging (MRI) record. Fifteen Flemish Giant rabbits were subjected to a single tibiofemoral compressive impact (ACLF), and 18 underwent a combination of anterior cruciate ligament (ACL) and meniscal transection (mACLT).
  
  
  
  All ACLF animals experienced ACL rupture, and 13 also experienced acute meniscal damage. All ACLF and mACLT animals showed meniscal and articular cartilage damages at dissection. Meniscal damage was documented as early as 4 weeks and worsened in 87% of the ACLF animals and 71% of the mACLT animals. Acute cartilage damage also developed further and increased in occurrence with time in both models. A progressive decrease in bone quantity and quality was documented in both models. The MRI data closely aligned with dissection notes suggesting this clinical tool may be a non-invasive method for documenting joint damage in lapine models of knee joint trauma.
  
  
  
  The study investigates the acute to chronic progression of meniscal and cartilage damage at various time points, and chronic changes to the underlying bone in two models of posttraumatic osteoarthritis (PTOA), and highlights the dependency of the model on the location, type, and progression of damage over time.
authors.affiliation: School of Biomedical Engineering, Colorado Sate University, Fort Collins, CO, USA. Electronic address: kfischenich@gmail.com.
authors.forename: K M
authors.initials: KM
authors.lastname: Fischenich
authors.affiliation: School of Biomedical Engineering, Colorado Sate University, Fort Collins, CO, USA. Electronic address: hmpauly1@gmail.com.
authors.forename: H M
authors.initials: HM
authors.lastname: Pauly
authors.affiliation: Orthopaedic Biomechanics Laboratories, College of Osteopathic Medicine, Michigan State University, East Lansing, MI, USA. Electronic address: keithdbutton@gmail.com.
authors.forename: K D
authors.initials: KD
authors.lastname: Button
authors.affiliation: Department of Radiology, Michigan State University, East Lansing, MI, USA. Electronic address: Ryan.Fajardo@radiology.msu.edu.
authors.forename: R S
authors.initials: RS
authors.lastname: Fajardo
authors.affiliation: Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI, USA. Electronic address: decampc@cvm.msu.edu.
authors.forename: C E
authors.initials: CE
authors.lastname: DeCamp
authors.affiliation: Orthopaedic Biomechanics Laboratories, College of Osteopathic Medicine, Michigan State University, East Lansing, MI, USA; Department of Radiology, Michigan State University, East Lansing, MI, USA. Electronic address: haut@msu.edu.
authors.forename: R C
authors.initials: RC
authors.lastname: Haut
authors.affiliation: School of Biomedical Engineering, Colorado Sate University, Fort Collins, CO, USA; Department of Mechanical Engineering, Colorado State University, Fort Collins, CO, USA. Electronic address: Tammy.Donahue@colostate.edu.
authors.forename: T L
authors.initials: TL
authors.lastname: Haut Donahue
mesh_terms: D000208:Acute Disease; D000818:Animals; D016118:Anterior Cruciate Ligament / Q000601:surgery; D000070598:Anterior Cruciate Ligament Injuries / Q000150:complications / Q000000981:diagnostic imaging*; D001842:Bone and Bones / Q000000981:diagnostic imaging*; D002358:Cartilage, Articular / Q000000981:diagnostic imaging*; D002908:Chronic Disease; D004195:Disease Models, Animal; D018450:Disease Progression; D007718:Knee Injuries / Q000150:complications / Q000000981:diagnostic imaging; D008279:Magnetic Resonance Imaging; D008592:Menisci, Tibial / Q000601:surgery; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging* / Q000209:etiology; D011817:Rabbits; D000070600:Tibial Meniscus Injuries / Q000150:complications / Q000000981:diagnostic imaging*; D055114:X-Ray Microtomography
keywords: Acute; Cartilage; Chronic; MRI; Meniscus; Trauma