May 2006

An MRI May Get Right To The Cause

It doesn’t come cheap, but in the long run, getting a firm diagnosis may save time, trouble and unnecessary less-conclusive testing.

It wasn’t that long ago that X-rays were the only diagnostic tool available to veterinarians for determining the cause of lameness. But X-rays have drawbacks, including the inability to show problems with tissues other than bone and the fact that abnormalities and changes seen on X-rays aren’t necessarily the cause of the horse’s pain.

X-rays show bone clearly, top photo, while on MRIs, lower photo, the very dense tissues like hoof wall and the outer, cortical layer of bone appear black and fluids like blood or joint fluid are the brightest. Tendon is in between. What looks like a B-B pellet in this horse’s coffin bone is a shoe-nail artifact.

The advent of ultrasound was a major step forward in being able to see injury to soft tissues such as tendons and ligaments and smaller structures inside and alongside joints that function to stabilize them. However, the most important part of the horse’s body when it comes to lameness is the foot, and it can’t be completely…