A 58-year-old woman presents to the neurology outpatient clinic with a progressive loss of function over the past 72 hours following a fall at home, where she hit her lower back. She reports developing weakness and flaccid paralysis in her left lower extremity, along with diminished proprioception and vibratory sensation in the same limb. Concurrently, she notes a complete loss of pain and temperature sensation on the right side of her body, starting from the mid-abdomen downwards. She denies any bladder or bowel incontinence. Routine blood work reveals the following: Considering the presenting symptoms and physical findings, what is the most likely spinal cord syndrome, and what is the immediate next step in confirming the diagnosis and initiating appropriate management?