This painful problem, where the spinous processes of horses begin to touch and rub together, is becoming far more common.
It isn’t the end of a horses career often, but it’s absolutely essential to create a strong back and core so the horse’s muscles can take over the job of lifting those spinous processes apart.
In my book, it’s completely unethical to ride a horse in this type of pain without a plan to rehabilitate the back.
Why is it so common? Some theories:
Riding young horses before the growth played have closed
Poor saddle fit
Horses with poor posture and a weak core and back
Riders with poor postures
The first picture indicates the spine of a healthy horse where the rider sits – on the weakest part of the back, already at risk for dropping and bringing the vertebrae too close together.
The only ethical thing to do if you ride, is to teach your horse healthy postures and bring the back up.