title: Abnormal perfusion in patellofemoral subchondral bone marrow in the rat anterior cruciate ligament transection model of post-traumatic osteoarthritis: a dynamic contrast-enhanced magnetic resonance imaging study.
abstract: OBJECTIVE
  Although anterior cruciate ligament (ACL) injury is a well-recognized risk factor for developing knee post-traumatic osteoarthritis (PTOA), the process in the patellofemoral (PF) joint after ACL injury is still under-researched. Our aim was to investigate the perfusion changes in PF subchondral bone marrow in the rat ACL transection (ACLX) model of PTOA using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).
  
  
  METHODS
  Eighteen male Sprague Dawley rats were randomly separated into three groups (n = 6 each group): a normal control group and groups receiving ACLX and sham-surgery, respectively, in the right knee. Perfusion parameters in the patellar and femoral subchondral bone marrows of all rats were measured on DCE-MRI at 0, 4, 8, and 16 weeks after respective treatment. After the last MRI at week 16, the rats were sacrificed and their right knees were harvested for histologic examination. In addition, to observe the long-term histologic change in PF joints, 9 additional rats (n = 3 in each group) were included and sacrificed at week 32 for histologic examination.
  
  
  RESULTS
  In the ACLX group vs the sham and control groups, the perfusion parameters were significantly changed in both patellar and femoral subchondral bone marrows at week 16. Histologic examination revealed cartilage defects in ACLX rats at 32 weeks after surgery.
  
  
  CONCLUSIONS
  These data point to a possible functional relationship between subchondral bone marrow perfusion abnormalities and cartilage breakdown in PTOA. Moreover, the perfusion parameters derived from DCE-MRI can potentially serve as biomarkers of early OA.
authors.affiliation: Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC; Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan, ROC; Department of Medical Imaging and Translational Imaging Research Center, Taipei Medical University Hospital, Taipei Medical University, Taipei, Taiwan, ROC.
authors.forename: P-H
authors.initials: PH
authors.lastname: Tsai
authors.affiliation: Department of Pathology and Laboratory Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan, ROC; Department of Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC.
authors.forename: H-S
authors.initials: HS
authors.lastname: Lee
authors.affiliation: Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital at Linkou, Institute for Radiological Research, College of Medicine, Chang Gung University, Taoyuan, Taiwan, ROC; Institute of Biomedical Sciences, Academic Sinica, Taipei, Taiwan, ROC.
authors.forename: T Y
authors.initials: TY
authors.lastname: Siow
authors.affiliation: Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC; Department and Graduate Institute of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan, ROC.
authors.forename: C-Y
authors.initials: CY
authors.lastname: Wang
authors.affiliation: Department of Mathematics, Tamkang University, Taipei, Taiwan, ROC.
authors.forename: Y-C
authors.initials: YC
authors.lastname: Chang
authors.affiliation: Institute of Biomedical Sciences, Academic Sinica, Taipei, Taiwan, ROC.
authors.forename: M-H
authors.initials: MH
authors.lastname: Lin
authors.affiliation: Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC.
authors.forename: Y-C
authors.initials: YC
authors.lastname: Hsu
authors.affiliation: Department of Orthopedics, School of Medicine, College of Medicine, Taipei Medical University and Hospital, Taipei, Taiwan, ROC.
authors.forename: C-H
authors.initials: CH
authors.lastname: Lee
authors.affiliation: Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei, Taiwan, ROC.
authors.forename: H-W
authors.initials: HW
authors.lastname: Chung
authors.affiliation: Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC; Department of Medical Research, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC. Electronic address: gsh5@seed.net.tw.
authors.forename: G-S
authors.initials: GS
authors.lastname: Huang
mesh_terms: D000818:Animals; D000070598:Anterior Cruciate Ligament Injuries; D001853:Bone Marrow / Q000098:blood supply*; D003287:Contrast Media; D005269:Femur / Q000098:blood supply*; D007718:Knee Injuries / Q000150:complications; D008279:Magnetic Resonance Imaging; D008297:Male; D020370:Osteoarthritis, Knee / Q000209:etiology / Q000503:physiopathology*; D010329:Patella / Q000098:blood supply*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D003287:Contrast Media
keywords: Anterior cruciate ligament; DCE-MRI; Patellofemoral joint; Perfusion; Post-traumatic osteoarthritis; Subchondral bone marrow