• There is loss of infra-patellar fat pad and corresponding cranial expansion of the joint fluid shadow.
  • There is an appearance of caudal expansion of the joint fluid shadow obscuring fascial plane detail which was evident on the normal stifle.
  • Irregularity of the fabellae.
  • "Tide mark" line of osteophytes parallel, and just caudal to the line of the trochlear ridge.
  • Although these radiographic changes might seem subtle, at arthrotomy extensive and well developed osteophytes will be apparent.