Open the Horse's Thoracic Cage

Today we get to hang out in one of the most thrilling complex and wellbuilt skeletal structures in the body the thoracic cage. While thrilling might be a stretch unless youre an anatomy geek like me suffice it to say that this region and its resilient flexible function has potential implications in respiration saddle fit behaviour body control bending collection energy levels the ability to be symmetrical and free in movement and more. And Im not just talking about your horse. If you the rider cannot move well through your thoracic cage youre going to be impacting your time in the saddle more than you realize. 

The main function of this incredible feat of nature that is the thoracic spine and cage is to protect the heart lungs spinal cord and the many essential vessels moving through this region.
The Horse
First the healthy functioning of the thoracic diaphragm is dependent on the mobility of the thoracic cage. The thoracic diaphragm is a large structure of muscle that separates the abdomen and thorax and connects to the ribs thoracic vertebrae and sternum and is crucial in thoracic respiration drainage pressure regulation digestion and overall vitality.
Second our equine friends have no clavicles collarbones but humans have two and these bones have a very special function in our ability to exist in verticality.
And third when we ride our horses were on top of and potentially compressing this whole unit it  is all interconnected. The mobility or lack thereof of the thoracic spine will impact the mobility of the rib cage and will impact the mobility of the sternum and will have an effect on the heart and the lungs on breathing on the surrounding muscles and on all the many places this region attaches via fascia dura and circulation including the pelvis cervical spine and cranium. So yep were in big territory here especially if things arent moving.
Now on to the geeky stuff! Horses have a lot of ribs 18 to be exact compared to our 12 with most articulating connecting at the head of the rib with two thoracic vertebrae once with the rib tubercle at the transverse process of the vertebrae the costotransverse joint and once at the meeting of the two vertebrae the costovertebral joint. The sympathetic ganglion chain sits in front of the rib heads. The ganglia of the sympathetic nervous system deliver information to the body about stress and