Many horses go through life with a 'variety pack' of physical and mental issues that come with doing their job. Horses can only tell us that their body doesn't feel good by slowing/shutting down, rushing to escape it, or by acting out in the moment of discomfort or pain. And like people, extended periods of physical discomfort cause reactive and anxious behavior.
There are so many different things that can cause/trigger various behaviors and physical problems. A hoof imbalance can cause a hollow posture, which can cause painful pressure points from a saddle, which can show up as head tossing or rearing. If the rider becomes tense and frustrated, their own tight posture and clenched hands can feed into the problem.
It takes a whole horse (and rider) approach with strong detective work and solid strategies for EVERY individual issue to unwind these situations. Leaving even one source of pain or behavioral trigger unsolved can keep the unhealthy loop going.
Sadly, too many horses are retired or sold because of "unidentifiable" lingering problems. If any of this sounds familiar, please contact me and let's see what we can do for you and your horse.