10/21/2026
"Don't forget about the thoracolumbar fascia!"
When we think about the muscles along a horse's back, we often think of the longissimus dorsi, one of the major muscles responsible for extending and bending the spine.
But what about the connective tissue that lies over it?
Meet the thoracolumbar fascia (TLF)!
This broad sheet of connective tissue extends along the horse's back, covering the longissimus dorsi, which runs alongside the spine. Farther back, in the region of the hindquarters, fascial tissue also separates portions of the longissimus dorsi and gluteus medius.
So the TLF isn't simply a covering around one muscle. It's part of the connective-tissue anatomy of the back, closely associated with the muscles beneath and around it.
Human research suggests that the thoracolumbar fascia may play a role in pain, sensory feedback and the way connective-tissue layers glide against one another.
But how much of this applies to horses?
A 2025 review by Harrison and colleagues highlights fascia as an area that deserves much more research in equine back function and rehabilitation.
For those of us already working with fascia, this is an exciting area to explore. How does fascia contribute to how horses experience back discomfort or sense movement? What happens to its properties when the tissue is under stress? We may observe changes in tissue feel and mobility during hands-on work, but understanding the underlying mechanisms and how they relate to pain and movement requires further research.
📚 Want to explore further? Harrison et al. (2025), Functional anatomy of the equine thoracolumbar spine related to equine back rehabilitation.
https://doi.org/10.1016/j.eqre.2025.100027