Aloha! You're speaking to Dr. Michael SalkinWould you describe Tonto as ataxic - "drunken sailor" - on his hind legs? Are they crossing underneath him? Is he dragging his paws/nails? A simple soft tissue injury is always possible but when both hind legs are involved, a myelopathy (spinal cord disorder) is considered. The most common of the myelopathies is intervertebral disk disease - a "slipped disk" which can be quite painful and account inappetence.Tonto's vet will want to carefully palpate (feel) Tonto's spine/back to see areas of hyperpathia (increased sensitivity) exist. Tonto's conscious proprioception (knowing where one's legs are in space) and nociception (deep pain perception) should be assessed as well as they give us a prognosis . In most cases, a simple disk will remiss within 3 weeks. An emergency situation exists if peracute (sudden) paresis (weakness) or, indeed, paralysis is noted.Please respond with further questions or concerns if you wish.