Signalment: 16 year-old male neutered American Bulldog mixed breed; Primary complaint: Progressive difficulty rising and walking with episodes of ‘collapse’ affecting the pelvic limbs. History: The dog presented with progressive difficulty when rising and ambulating over several years and had been diagnosed with multi-focal osteoarthritis by a veterinary orthopedic surgeon. He had no obvious neurological deficits and had radiographic evidence of multi-focal degenerative joint disease. The clinical signs were often worse in the summer. Unilateral tarsal arthrodesis had been performed in the past, because of a traumatic tendon injury. Recently the dog had developed episodes of pelvic limb weakness and difficulty rising in the morning accompanied by whining and growling. He also had difficulty navigating steps and was reluctant to engage in play. He had increased panting and sought out cool places. Current medications included carprofen 50 mg once daily and tramadol 50 mg BID for medical management of the osteoarthritis.