Today’s case is an 8 year old St. Bernard with non weight-bearing lameness and firm swelling on the distal tibia of the right hind limb.
Case originally posted on August 13, 2007
Teaching and learning about veterinary diagnostic imaging.
Today’s case is an 8 year old St. Bernard with non weight-bearing lameness and firm swelling on the distal tibia of the right hind limb.
There is a large, expansile, destructive osseous lesion of the distal right tibia with cortical destruction, most severe at the caudal and medial margins. There is also mild, irregular periosteal proliferation and soft-tissue thickening at the site.
Primary bone tumor
Osteosarcoma
This lesion is characteristic of a primary bone tumor. The location and expansile, destructive pattern are features to look for. A fungal osteomyelitis would tend to have more productive bone and is often multifocal. Osteosarcoma is most likely in this case.
vickie says
I thought there might have been some lysis in the femoral metaphysis as well?
Allison Zwingenberger says
The whole limb is affected by disuse osteopenia, making the cortices thin and causing the relative lucency of the metaphysis on the lateral projection.