Sue Dyson pain scale: What is it and how does it work.

Every rider knows the frustration of a horse that seems resistant, tense, or "naughty" under saddle. But what if those behaviors are actually a cry for help?

Equine orthopaedic specialist Dr. Sue Dyson has spent years showing that many of the signs riders write off as attitude or a training gap are, in fact, clear indicators of pain [1]. To help owners, riders, and vets recognize these signals, she developed the Ridden Horse Pain Ethogram (RHpE), better known as the Sue Dyson Pain Scale [1][3].

The scale gives you a structured way to spot subtle behaviors that reveal when a horse is uncomfortable, so problems tied to musculoskeletal pain get caught sooner. In the original development study, most of the 24 behaviors turned out to be at least ten times more likely in lame horses than in sound ones [1].

Before we go further: if you think your horse might be in pain, talk to your vet and get a proper diagnosis. This scale flags a pattern. It doesn't replace a lameness exam.

How the Sue Dyson pain scale works

The Sue Dyson Pain Scale is a peer-reviewed system built around 24 specific behaviors linked to musculoskeletal pain in ridden horses [1][3]. A horse showing 8 or more of the 24 markers is very likely in pain, not just having an off day. In a 2020 study of 60 riding horses, the median score was 9 out of 24. Horses with no lameness and a normal canter scored a median of 5, well under the pain threshold [2].

These include signs such as:

1. The ears rotated back or lay flat for five or more seconds

2. The eye lids closed or half closed for two to five seconds

3. Head in front of vertical > 30 degrees for ten or more seconds or more

4. The tongue exposed, protruding or hanging out

5. Head behind vertical > 10 degrees for ten or more seconds

6. The mouth open with separation of the teeth for ten seconds

7. Tail swishing

8. Head tilted, repeatedly

9. The bit pulled to one side (left or right)

10. A rushed gait, irregular rhythm in trot or canter, or repeated changes of speed in trot or canter

11. Repeated changes of head position not in rhythm with trot

12. Stumbles or trips repeatedly or repeated bilateral hindlimb toe drag

13. Head position changes repeatedly, moving from side to side

14. Gait too slow: may resemble passage-like trot

15. Sudden change of direction or spooking

16. Bucking or kicking backwards (one or both hindlimbs)

17. Rearing (both forelimbs off the ground)

18. Hindlimbs do not follow tracks of forelimbs but deviated to left or right

19. Canter repeated strike off on wrong leg (incorrect lead) or change of leg in front and / or behind

20. Spontaneous changes of gait

21. Tail clamped tightly on the mid-line, or held to one side

22. Reluctant to move forward or stops spontaneously

23. Sclera is repeatedly exposed

24. An intense stare or looking zoned out, for five seconds or more

The scale works by scoring these behaviors during riding. Vets and trained professionals use it in clinical settings, but everyday riders benefit too, and that's the point of it: Dyson built the RHpE to travel outside the exam room, not stay locked inside one.

By learning the common markers, you'll be better equipped to:

• Spot when your horse's behavior may not be attitude, but pain
• Record patterns and changes in behavior for your vet
• Advocate for your horse's comfort and welfare

Conclusion

The Sue Dyson Pain Scale is a tool, not a diagnosis. Horses can show similar behaviors because of poor saddle fit, rider imbalance, or a lack of fitness, so context always matters. One study even found no meaningful link between how lame a horse looked and its RHpE score [4], which tells you something worth sitting with: pain can be loud in behavior and quiet in gait.

If you suspect pain, the next step is a thorough check by your vet, and possibly a physiotherapist too.

Once pain has been identified and addressed, it's worth building long-term comfort into the horse's routine. Balance pads are one option: they train the deep core muscles that support the spine, which helps with stability and coordination under saddle.

For more information, feel free to take a look at our blog about the benefits of balance pads and our blog about how to use balance pads, which includes an 8-week schedule to improve proprioception.