Flexion tests reliability ?

[chesnutcraze]

Hi all,
My horse is 3/10 lame on RF on hard ground. Pretty much 95% sound on soft. Vet believes the cause is partially compensation for some ongoing LF lameness that took quite a few months to sort out.

On the vet visit last week, he had a positive fetlock flexion test of RF. He was probably 6-7/10 lame after flexions, and was clearly very sore when the flexion was being done. However there was nothing significant to note on his X-rays? No marked arthritic changes, no signs of laminitis, good sole depth and foot balance etc. There is no heat, swelling or pain on palpation to indicate soft tissue damage. The vet thinks it is joint related, even if nothing is showing on X-ray.

The vet is coming out again soon to do nerve blocks (he had to be sedated for X-rays so weren’t able to nerve block this time) but now I’m not sure what to expect. Obviously if there is nothing significant shown on X-ray the next route would be to investigate soft tissue, but with the increased lameness on hard ground and slight stiffness in cold weather, the vet is fairly convinced it’s a joint/bone problem.

So I guess the question is, how reliable are flexion tests, especially when nothing significant shows on X-ray? Can flexion tests highlight inflammation that may not be visible?

 

[milliepops]

Not an expert by any means and i know there are issues with flexion tests. But my most recent lameness work up had positive flexion, nothing on ultrasound and nothing on x Ray. They couldn't see her issue until she had an MRI. With that degree of lameness I would be wanting to continue investigations.

 

[chesnutcraze]

Not an expert by any means and i know there are issues with flexion tests. But my most recent lameness work up had positive flexion, nothing on ultrasound and nothing on x Ray. They couldn't see her issue until she had an MRI. With that degree of lameness I would be wanting to continue investigations.

We have already done MRI’s last year when lameness started, and it showed nav bone changes to both fronts + ligament damage in both fronts. Ligament damage was much worse in LF, and more of a slight inflammation in RF. Rehabbed from this and he was going okay, until lameness switched legs and suddenly became lame on RF. I cannot afford another set of MRI’s. Most recent X-rays show no further degeneration of nav bone since last year, and the bony changes were v mild in the first place.

 

[BronsonNutter]

Flexion tests can highlight any injury or condition that is made worse by the limb being flexed - so not just joints/bones (e.g. arthritis, OCD), but also injuries to any ligaments or tendons that are stretched or squashed in the process. For example, collateral ligaments of joints, annular ligaments etc, and these wouldn't show up on x-rays unless there were changes at the attachment site of the ligaments to bone. There needn't necessarily be any evident swelling with some of those injuries. Occasionally you can get an acute injury within a joint (e.g. a tear in the cartilage) that might not show changes on x-ray just yet, but then there would usually be increased fluid within the joint that would be able to be felt.
If the horse is that severely lame after flexion then I would say it is significant - many horses might be a 'bit off' after flexion for a few strides, but 6-7/10 is definitely painful.
Hope you can get to the bottom of it soon.

 

[Lady Jane]

3/10 lame means you have a problem. Flexion test helps to identify the problem, not tell you whether its a bone or soft tissue problem