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NAVLE（北美执业兽医考题）Day 449
单选题，正确答案是100分，非正确答案为0分，Good Luck！
A 5-year old male castrated Mastiff presents for left pelvic limb lameness. The medial aspects of both stifles are thickened. Manipulation of the left stifle reveals cranial motion of the tibia relative to the femur and a clicking sound from the joint on flexion and extension. What is the most likely diagnosis?5岁的雄性已绝育獒犬出现了左侧后肢跛行。其双侧膝关节内侧面都变厚了。左侧膝关节的胫骨相对于股骨的向前运动和关节屈伸时有咔嗒声。最有可能的诊断是什么Find out the answer by clicking on one of the listed choices. Good luck!点击列出的选项找出答案，祝大家好运
