The Equine Pelvis & Some Scientific Facts

At a recent event i attended David Bainbridge did a fascinating talk about his research on the Horse’s Pelvis. I wanted to share some of the interesting facts as I work with many clients that talk to me about SI pain and diagnosis.

David is a vet, science writer, reproductive biologist and veterinary anatomist at the University of Cambridge.

Over hundreds of millions of years, the pelvis of land vertebrates has evolved in concert with nearby structures to perform a variety of functions. The pelvis/sacrum/cranial tail complex is the musculoskeletal unit which:

1) Transfers supportive and propulsive forces from the hindlimb to the trunk

2) it’s part of the spinal column

3) serves as the point of attachment of many spinal, abdominal and hindlimb muscles

4) contains within its major components of the alimentary, urinary, reproductive, vascular, lymphatic and nervous systems

The talk went into much detail about the functions of the pelvis - but for your interest I will focus on the facts that will help when discussing any issues with the horse’s pelvis.

In many ways it is the ‘centre’ of the body’s musculoskeletal system. Problems will generally show in the horses performance as it is key to the propulsive forces.

Due to the depth of the SI joint and the complex connections it is extremely difficult to diagnose lameness or poor performance related to the pelvis. While modern imaging techniques may help, the fundamental problem remains that the equine pelvis is essentially ‘unmanipulable’ by human hands.

So therefore therapists should not be diagnosing anything related to the  SI joint. Only a vet can assist in this area. Many times I have worked with clients whom have said there therapist has diagnosed or pointed to a problem in the SI. David’s research and knowledge highlights that this is extremely dangerous - as it cannot be felt due to its positioning. The SI has very little movement at all, and he believes it is very unlikely that it even has any rotational movement also. The SI could still be very painful if diseased despite its lack of movement.

He also spoke in depth about treatment options for problems in this area. He said to inject the SI is extremely challenging, as the needle has a very small good contact area and it’s really deep and on an angle. He said of one of the vets he works with, it’s almost impossible to achieve it well. I know from one of the dissections I attended the horse we were looking at had been injected in the SI. The needle had slightly missed the good contact area and had chipped in to the edge of the bone - likely causing other long term problems for that horse.

I found this talk really helpful and he gave a clear direction on his findings. Most therapists I find brilliant to work with, but if you work with one that is diagnosing around the SI area good or bad you need to question this. It’s not able to be manipulated by the human hand, hence the difficulty to feel any problems in that area.

I hope you find these facts as interesting as I did and thanks for taking time to read.