What is your diagnosis? Radiographic diagnosis - Severe osteolysis of the proximal two thirds of the tibia with associated soft-tissue swelling

摘要

A 4.5-year-old spayed female cat was admitted for evaluation of chronic left hind limb lameness. According to the owner, the lameness originally was mild with an acute onset and progressed to a severe intermittent non-weight-bearing lameness over a 3- to 4-month period. For several days prior to evaluation, the cat had been hiding, and the owner noticed that the left stifle region was large. On physical examination, the thigh muscles were severely atrophied, and the cat would not bear weight on the left hind limb. A firm swelling was evident extending from the stifle joint to the middiaphysis of the tibia. Signs of pain were elicited on palpation of this area. In addition, range of motion in the stifle joint was limited. Radiographs of the left hind limb were obtained (Fig 1).