the troublesome concept of clinical significance

The Troublesome Concept of Clinical Significance

"Clinically significant" is a term used in healthcare and medicine to describe findings or results that have practical and meaningful implications for a patient's diagnosis, treatment, or prognosis. Clinically significant findings are those that are not just statistically significant (meaning they are unlikely to occur by chance) but also have a NOTICEABLE impact on a patient's health or well-being.

Human healthcare greatly benefits from the ability to obtain direct feedback on symptoms from patients.

When it comes to determining if an abnormality detected on a horse's radiographs is clinically significant or not, the veterinarian has to determine IF and HOW the issue is troubling the horse.

This is a problem because it is highly subjective and depends on what you have learned to observe.

I often say – I have never met a difficult horse that did not turn out to have something wrong with them. However, difficult horses don’t typically go to vets first. They come to trainers like me. In my experience, I have successfully worked with many of these horses. However, time has revealed that most of them had underlying physical issues, and all I did was push these horses to tolerate discomfort. Fortunately, I have also encountered horses that I couldn't help until they received assistance from horse health professionals such as vets, farriers, body workers, equine dentists, and saddle fitters. I witnessed a remarkable transformation in their ease of training after these interventions.

Therefore, these horses and professionals have taught me to recognize early signs of soundness issues when I struggle to influence a horse's confidence in what I am asking it to do. There is not a clinic I conduct where I do not refer at least one horse to an equine health professional.

However, occasionally, a client gets stuck. The horse is "not quite right," but it has been challenging to pinpoint the issue. Potential problems have been identified, such as spurs, OCD lesions, calcified tissue planes, etc., but these have all been deemed "not clinically significant" because it cannot be confirmed that the horse is troubled by them.

This horse is one of those examples, and I hope his story sheds light on something that might be helpful.

This horse came to me with challenging behavior at a clinic that raised red flags for soundness issues. I referred him to the vet, and he was subsequently diagnosed with hoof issues, and corrective farrier work was performed. However, something still doesn't seem right. While it could still be related to his feet, further investigations revealed that he has mild arthritic changes in his right hock and a small spur on his left stifle. Nevertheless, these issues have been labeled as NOT clinically significant because when my client demonstrates how the horse responds on the lunge, his behavior is dismissed as being "a bit fresh," and nothing significant is observed

However, let's delve deeper into his behavior on the lunge.

Firstly, the horse's response varies from one rein to the next. He is often unwilling and hard to motivate to move forward on the right rein verses the left. On the right rein, he also changes his head position from counter-bending to very low, all of which affect the loading on his joints during motion. However, is this reluctance due to discomfort, compensation, or simply laziness? And why does lazy disappear on the left rein?

Moreover, he consistently reacts explosively when asked to canter, exhibiting bunny hops, kicking out, and becoming highly emotional. Is he physically struggling with the canter gait, or is he merely feeling "fresh"? And why does he quickly return to being less emotional when he returns to trot and walk?

I believe it is too early to rule the mild arthritis and stifle spur as not clinically signficant because these things he is doing on the lunge I see as hind end soundness red flags

It's common to hear horses labeled as "stoic" for hiding their discomfort. In reality, they don't hide it; they compensate by altering their movement, loading, and resistance, all of which occur before obvious lameness becomes apparent.

Therefore, I am sharing this post to emphasize that assessing behavior is highly subjective, and challenges arise when we consider the notion of "clinical significance."