Clinical history A 7 year old quarter horse mare was kept in a pasture - she escaped from the pasture with several other horses and was struck by a car - she was severely lame and brought to the clinic for examination 7 days after the trauma. Radiographs were made of the left fore foot, what is your radiographic diagnosis? Radiographs Radiographs Radiographic diagnosis
- Acute articular fracture dorsolateral corner proximal P1
- Chronic navicular fracture - DD bipartite navicular bone
- Osteochondroma dorsomedial aspect proximal P1 - DD chip fracture, osteochondrosis
Enlargements Comments The fracture of P1 is best seen on the oblique view. The navicular injury was thought to show fibrous union of an old fracture - the possibility of a bipartite sesamoid bone should be included in the differential. The bony fragment dorsal to the MCP joint is most likely an osteochondral fragment - the absence of an adjacent bone defect makes a chip fracture or an osteochondrosis dissecans less likely.
