I met a horse last week, which really highlighted the conformational defect of “tied in at the knee”, and of course triggered me to inform my readers.
I`ve read all about conformation for various exams, but have yet to see such a good example of this. Tied in at the knee refers to a horse who has too small (or light) a tendons for their size. You can see this by there being a marked difference between the circumference of the leg below the knee and above the knee. It almost looks like an elastic band has been tied around the leg below the knee.
So why is this such a conformation no-no? Having a smaller circumference below the knee gives less room for the tendons and ligaments. Horses don`t have muscle below the knee and hock, so their soundness relies on their strong, long tendons. If the tendons do not have sufficient room then they may become damaged due to friction on the carpal bones or against each other. The tendons are discouraged from growing as they get stronger. This means that forward movement is restricted and the horse may have a shorter stride than expected. Horses who are tied in at the knee are not able to perform at high speed, and the tendons will struggle to absorb the concussion effects of jumping.
Tied in at the knee conformation cannot be altered, but the horse cannot be expected to work at a high level and stay sound. Deep going will put more strain on the tendons so this should be avoided, and the owner/rider adapt the horse`s workload to the individual. If the horse becomes sore or backs off work then his workload needs to be reduced.
A horse who is tied in below the knee is more prone to tendon injuries, particularly to the cannon bone region, because of the limited strength of the flexor tendons. Horses with this conformation also usually have small accessory carpal bones, which struggle to support the horse`s leg when weight bearing. Subsequently these horses are more suited for dressage and driving, in which the weight is encouraged off the forehand and onto the hindquarters.