A 2-year old male castrated mixed breed dog presents for an altered gait after being hit by a car. On physical exam, the thoracic limbs had decreased biceps and triceps reflexes and decreased muscle tone. The pelvic limbs had hyper-reflexive patellar and gastrocnemius reflexes and increased muscle tone. Where is the spinal cord lesion？
一只2岁雄性已绝育混种犬由于被车撞了以后步态改变前来就诊，体格检查后发现其前肢二头肌和三头肌反射降低，肌张力减弱。后肢膝盖以及腓肠肌反射过强，肌张力增加。其脊髓损伤的部位在哪里？