Medial Patellar Luxation
The patella acts as a fulcrum during normal extension of the knee joint. It glides up and down within a groove that forms the front of the knee joint. In some dogs, the patella luxates (dislocates) out of this normal groove. The consequence of this luxation is an inability to properly extend the knee joint. As well as the lameness caused by the mechanical deficiency of the affected knee, there are varying degrees of pain and osteoarthritis. In medial patella luxation the patella moves to the inside, or medial, aspect of the patella groove.