A 10-month-old 26.8-kg castrated male Golden Retriever was referred because of a 5-month history of progressive pelvic limb ataxia and paresis. Prior to referral, the dog was evaluated by the primary veterinarian and empirically treated with prednisone (20 mg, PO, q 12 h, on a tapering schedule), doxycycline (unknown dosage), and physical therapy. The dog’s pelvic limb ataxia improved with medical treatment but worsened as the prednisone dosage was tapered.
On referral examination, the dog was bright, alert, and responsive and had abrasions on the dorsal aspect of digits 2 and 3 of the pelvic limbs bilaterally. The nails