It’s so frustrating when your horse is lame without a clear indicator. No huge gash pouring blood, very little heat and swelling. But definitely not right.
When the vet comes out the first thing they look at is the horse trotting up, to see if there’s any abnormality in their gait, such as placing the foot down one side first, or not flexing a joint as much as it’s counterpart.
Then they inevitably suggest nerve blocking. At this point you hope your horse’s problem is in his foot, not his shoulder, otherwise you could be embarking on a nerve-blocking Safari.
Nerve blocking is a very straightforward process in which general anaesthetic is injected into the long nerve that travels down the leg, one on each side. Once the limb has been numbed, after ten minutes, the horse is trotted up and reassessed for lameness. The level of lameness after a nerve block allows you to identify the area of injury.
Logic dictates that you want to nerve block the distal part of the limb first, so the vet will inject the foot just below the pastern. If they think the problem is on one side of the limb then they will inject just one nerve.
After looking at the horse trot up in a straight line and on the lunge the vet will then make a decision as to if the level of soundness has improved or not.
If not, then unfortunately it means another injection; either at the same point of the leg but on the other side, or higher up the leg.
At the point in which the horse becomes sound you can identify the joint/area/tissue that is injured. Then a closer inspection and comparison may be done to try and shed some light onto the problem. Failing that, the vet can make some educated guesses and suggest the next step.
For example if the horse comes sound at the hock nerve block the vet may think that the horse needs an X-ray of the hock to see if there are any bony changes which are causing pain and subsequent lameness.
Nerve blocking allows us to pinpoint the area that needs further investigation, instead of scanning it X-raying the whole limb, will ultimately save time and money; hopefully solving the problem quicker and bringing the horse back to soundness.
However it would be far easier if horses could tell us where they hurt!