Conditions or ailments that are the cause of a problem that you see - your observation.

Your vet may diagnose

Rein Lameness

Synonyms: Cat Trot or Bridle Lameness, Behavioral Lameness


"Rein lameness" is a gait abnormality under saddle at the trot that is a form of resistance, and does not result from pain. In some cases, it can be very hard to distinguish it from a pain-induced lameness.

It most often appears as a "head nod" at the trot that mimics front limb lameness. Some call this abnormality a "Cat Trot", where a horse takes a step toward a canter transition but then backs down.

A rein lameness may only be seen with one particular rider that is giving particular cues. It may not be present with another rider up. It should not be evident when the horse is subjected to a conventional lameness exam without a rider up.

However, it is thought that this movement pattern can become habitual if left untreated, and may eventually occur with other riders up, and even occur at the trot without a rider up.

Changes in riding and training techniques may be helpful to resolve this gait abnormality. They should be instituted soon after detection of the problem.

my vet's role


Rein lameness can be elusive and hard to diagnose and treat. In some cases, this "habit" may even occur when the horse is ridden by other riders or is trotted without a rider.

If "real" lameness (caused by an underlying condition resulting in pain) has been ruled out by a vet, then training and/or riding changes may be helpful to prevent this gait. However, it may become more difficult to resolve this problem as time passes, as this gait becomes more entrenched in the horse's way of moving.

my role

Questions To Ask Your Vet:
  • How do you know this gait abnormality is resistance and does not stem from pain?
  • What changes need to be made in training and riding to help alleviate this problem?

A vet should rule out lameness resulting from pain and physical factors before assuming that any gait abnormality is a "rein lameness".

Early detection, diagnosis and modification of riding and/or training technique is advised to prevent the behavioral gait abnormalities from becoming entrenched.

further reading & resources

Author: Doug Thal DVM Dipl. ABVP