【Abstract】 Objective To establ ish a three-foot weight-bearing canine model to imitate the biomechanical loading environment of the human’s hip joint. To observe and compare the kinetic changes of hind l imbs between normal and three-foot weight bearing canines. Methods Using 10 beagles, three-foot weight-bearing canine models were made by fixing unilateral wrist joints at 90º flexionally. The changes of ground reaction forces and the time of standing phases (Ts) of the hind l imbs were compared by 3-D gait analysis pre- and postoperatively. Results Canines could walk well with three l imbs after the fixation of one fore l imb. However, the gait pattern changed tremendously. The canine walked jumpily by raising its head and neck, and the bilateral hind l imbs kept contacting ground alternately. Ts of ipsilateral hind l imb was (0.48±0.04)s, and Ts of contralateral hind l imb was (0.46±0.06)s. Although, the time durations were increased a l ittle, but there were no significant differences when compared with that of normal canines (0.43±0.05)s (P gt; 0.05). The vertical ground reaction force (Fz) of ipsilateral hind l imb
was (4.63±0.85) body weight, and the Fz of contralateral hind l imb was (4.78±0.49) body weight. There were significant increases when compared with the Fz of normal canines (3.26±0.48) body weight (P lt; 0.05). The peak acceleration force of the ipsilateral hind l imb was (0.80±0.30) body weight. There was significant increase compared with that of normal canines (0.72±0.13) body weight (P lt; 0.05). The peak acceleration force of the contralateral hind l imbs was (0.68±0.22) body weight, there was no difference compared with that of normal canines (P gt; 0.05). The peak deceleration forces of the ipsilateral and contralateral hind l imbs were —(0.26±0.14) body weight and —(0.13±0.05) body weight separately. They decreased significantly when compared with that of normal canines —(0.43±0.13) body weight (P lt; 0.05). In normal canines, the upper l imbs were main load bearing
l imbs, they could bear 62.8%±2.4% of body weight. However, the hind l imbs could bear only 37.2%±1.8% of body weight. On the contrary, in three-foot weight-bearing canines, the hind l imbs became the main load bearing l imbs, they could bear 59.1%±6.7% of body weight. Conclusion Three-foot weight-bearing canine model can be used as a candidate animal model to research the effects of biomechanical loading on the progression of hip joint diseases.
Citation： LI Hongshuai,ZHANG Changqing,BAI Yuehong,ZHOU Jun,ZENG Bingfang. KINETIC CHANGES OF CANINE’S HINDLIMBS AFTER FIXATION OF ONE FORELIMB. Chinese Journal of Reparative and Reconstructive Surgery, 2008, 22(1): 66-69. doi: Copy