1. Sedate the dog whenever possible.
2. Take images of only one stifle at a time.
4. Get the other soft tissues out of the way. (that would be fat dog bellies and, ahem, - in boy dogs- other things)
5. With sedated dogs, it is simpler to get a straight caudocranial than a craniocaudal view. The trick with this view is to rotate the pelvis slightly (lift the good leg up) so that the femur and tibia are straight, rather than taking the shot with the leg out to the side.
6. Don't overexpose soft tissues. If you can't readily see the soft tissues of the joint (not just the bone), take an additional radiograph and lighten up the exposure. Sometimes you have to really underexpose the bone (get it bright white) to see the soft tissues.
BIG INDICATORS and some practical tips on rad interpretation.
The first Big Indicator to look for is SWELLING. The best way to improve your skill at detecting swelling is to know what the normal joint looks like. There are two opacities in the joint, fat and water. (Remember that when we refer to "water opacity" in radiology, it does not always mean that there is literally water present. Soft tissues are composed mostly of water and can't be distinguished from fluid in radiographs. This is why you can't distinguish bladder wall from urine, or bowel wall from fluid contents, for instance.)
The second Big Indicator you will see is the formation of ENTHESIOPHYTES. Don't feel bad if you've never heard of enthesiophytes – it's a term you usually only hear in radiology. An enthesis is the point of bone origin (or insertion) of a ligament, tendon, or joint capsule. An enthesiophyte is an area of mineralization/ossification at the enthesis.
The third Big Indicator to look for is DISPLACEMENT of the (single) popliteal sesamoid. It normally lives just above - or level with - the edge of the tibial plateau
The fourth Big Indicator would be OSTEOPHYTE formation.
Go here for the pictures and the discussion
