Sorry folks – it’s been a while since my last blog. I have been buying a house and working six days a week to keep up with the volume of work.

This blog is about unengaged hindquarters. Now I know this is a subject I have written about before, but I’m going to write about it again as I have over the last few weeks seen several horses that look like this (see first image). One of them was bought by a client of mine from a so-called ‘professional’ trainer.

Tail Set Too High sm

Horses are born with lovely round hind quarters (see image of a foal). They are shaped this way because their vertebrae are moveable rather than fixed. The most movable are L1 to L4 (the area just behind the saddle and in front of the horse’s quarters). The reason for flexion here is to enable them to bascule (ie round their backs) when jumping.

Foal quarters

To see why this is important, we can compare the physiology of horses’ feet with that of other vegetarian animals. Unlike horses, goats, deer and antelopes have cloven hooves (see image of goat). Their spines are fixed and flat, while they have a high tail set. The cloven hoof acts as a shock absorber: these animals jump without arching their backs and tend to gain impulsion (accelerate) when approaching an obstacle. By contrast, horses do the complete opposite: they slow down coming up to an obstacle and arch their backs.


All cloven-hoofed animals have horns as weapons that they use when fighting. A horse’s only weapons are its feet, which is why horses’ hooves are a solid, round mass rather than cloven. If a horse become rigid over L1/ L4, they will begin to jump like a deer does. We have all heard the expression “jumps like a stag” – well thats not how a horse should jump!

So why does this rigidity occur in horses? Why Does the tail set get so high and the back get so flat that the horse’s back resembles that of a deer (see 3rd image: horse with flat back)?
It’s down to lack of engagement of the hind quarters – and the rider is nearly always to blame. The only time the rider would NOT be at fault would be if the horse had suffered a pathological condition over this area.

If the horse is encouraged to engage its quarters then the abdominal muscles will contract, which in turn brings the quarters into a more biomechanically correct outline, bringing the tail set down to where it should naturally be.

It’s all too easy to haul in the front of the horse and THINK you have a horse in a contact.
Ignore the back end at your peril though, as this way of going puts a tremendous strain on the sacroiliac (SI) joints. And when the SI joints are not working correctly through their full movement range, they are likely to need medication over time.

These three joints work reciprocally: sacroiliac – stifle – hock. So if any one of these is out of synchronisation, the entire mechanism of engagement goes wrong.

An easy way to check if your horse is working correctly and engaging its quarters is to feel the Gaskin muscle (just above the hock). If it feels hard then your horse is not working correctly and will need some help to rectify this.