Hurcules is a 9-year-old castrated male Boxer. He presented to his veterinarian for episodes of difficulty rising and pain that responded to non-steroidal anti-inflammatory drugs and tramadol. Signs would improve but then recur. A referral was recommended; however, it was declined initially. These episodes continued over six months until he became acutely unable to walk in all four legs. Prednisone was prescribed and he was referred to Southeast Veterinary Neurology (SEVN) for further evaluation.
On initial examination, he was bright and alert and was able to walk. His heart and lungs auscultated normally. There were strong, synchronous pulses. His peripheral lymph nodes and abdomen palpated normal. There was no pain in his joints. On neurological examination, his cranial nerves were normal. He had slightly low head carriage, but was not overtly painful on spinal palpation. Postural reactions were absent on the left side of his body, with the thoracic limb being more affected. Spinal reflexes (patellar and flexor withdrawal reflexes) were brisk and complete (normal). Here is a video of his gait.
Describe the gait. When evaluating the gait, decide if the patient is ambulatory or not. Are all four legs affected? Just the pelvic limbs? Just one side of the body? Are the steps long-strided ('upper motor neuron' in character) or short-strided (‘lower motor neuron’ in character).
What is your neuroanatomical localization?
What are your differential diagnoses? Take into consideration age, breed, rapidity of onset, progression vs static, painful vs non-painful, and neuroanatomic localization.