title: Section of the anterior cruciate ligament in the rabbit as animal model for osteoarthritis progression.
abstract: OBJECTIVE
  The purpose of this study was to determine whether instability of knee is a risk factor in the progression of osteoarthritis (OA).
  
  
  METHODS
  Twenty-four mature New Zealand White rabbits were randomly divided into four groups. The control group received 0.3 ml saline in the first, fourth and seventh days in the right knee, while the other three groups received the same dosage 4 % papain and its activator 0.03 M L-cystein. The P3w group knees were harvested at three weeks after the last papain injection, the P6w group knees received a sham surgery at three weeks and were harvested at six weeks after the last papain injection, while the P+ACLT group knees received ACL transection at three weeks and were harvested at six weeks after the last papain injection. Cartilage degradation of femoral condyles and tibial plateaus were evaluated by X-rays, macroscopy, light microscopic and transmission electron microscopy (TEM).
  
  
  RESULTS
  According to X-rays grade scale, macroscopic grade scale, light microscopic modified Mankin scale and TEM, in the P3w knees, cartilage degeneration of femoral condyles and tibial plateaus were significantly severe compared to those of the control group (P < 0.05), but the differences were not apparent in comparison with the P6w knees (P > 0.05). However, in P+ACLT knees, cartilage degeneration of femoral condyles and tibial plateaus appeared more severe in comparison with P6w knees, and the difference was significant (P < 0.05).
  
  
  CONCLUSIONS
  Instability of knee plays a significant role in increasing the severity of cartilage degradation in rabbit knees and should be considered as a risk factor in OA knee progression. Our data may suggest that reconstruction of knee stability may prevent or delay the progression of OA.
authors.affiliation: Department of Orthopaedics, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, Shaanxi, People's Republic of China.
authors.forename: Feng
authors.initials: F
authors.lastname: Li
authors.affiliation: Department of Orthopaedics, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, Shaanxi, People's Republic of China.
authors.forename: Zhanhai
authors.initials: Z
authors.lastname: Yin
authors.affiliation: Department of Orthopaedics, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, Shaanxi, People's Republic of China.
authors.forename: Hao
authors.initials: H
authors.lastname: Wu
authors.affiliation: Department of Orthopaedics, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, Shaanxi, People's Republic of China.
authors.forename: Zili
authors.initials: Z
authors.lastname: Qin
authors.affiliation: Department of Orthopaedics, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, Shaanxi, People's Republic of China.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Orthopaedics, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, Shaanxi, People's Republic of China. yushengqiu@yeah.net.
authors.forename: Yusheng
authors.initials: Y
authors.lastname: Qiu
mesh_terms: D000818:Animals; D016118:Anterior Cruciate Ligament / Q000473:pathology* / Q000601:surgery; D004195:Disease Models, Animal; D018450:Disease Progression; D005260:Female; D007593:Joint Instability / Q000473:pathology; D007719:Knee Joint / Q000473:pathology*; D008297:Male; D020370:Osteoarthritis, Knee / Q000175:diagnosis*; D011817:Rabbits; D012307:Risk Factors
keywords: ACL transection; Cartilage; Instability; Osteoarthritis; Risk factor