A cat was referred to the Cornell University Companion Animal Hospital for evaluation of difficulty walking, lethargy, and apparent pain in the back and pelvic regions. Two months prior to admission, the referring veterinarian examined the patient for lethargy and difficulty walking. A mildly elevated temperature ( I 03°F) and a possible aggressive bone lesion in the 12th thoracic vertebra were detected. No physical evidence of trauma or a bite wound could be found. However, a presumptive diagnosis of bacterial osteomyelitis was made. The cat was treated with antibiotics and corticosteroids, but the clinical signs did not improve.On current physical examination, the cat was in good general body condition, eating well, and had normal mentation. However, the cat had hyperesthesia over the cranial lumbar region, and was mildly ataxic in both pelvic limbs without proprioceptive deficits. The body temperature could not be obtained because the cat displayed severe aggressive behavior that was interpreted as a response to pain. The results of CBC, serum chemistry panel, and CSF analysis were within reference range. Serologic testing for FIV, FeLV, and Toxoplasmosis were negative.In routine radiographs of the thoracolumbar vertebral column, there was evidence of bony proliferation at the 12th thoracic vertebra (Fig. 1). On the lateral view, increased mineral opacity was superimposed on the vertebral canal at T12. The margins of this opacity were irregular and within the opaque area there were multiple, small, punctate, lucent areas. On the ventrodorsal view, the left pedicle of T12 was enlarged with irregular margins, increased in opacity, and projected into the vertebral canal. Myelography was attempted, but the examination was considered nondiagnostic due to opacification of the subdural space. In computed tomographic images, the left pedicle of T12 was

Construct stiffness in axial load varies with implant type. Implants that confer higher stiffness to the construct may result in greater fixation stability in tibial metaphyseal osteotomies.