It is rather sad, but certain parts of the body are just not "trendy". Even the clients who visit us can name various muscles (piriformis, trapezius, etc) but it is unlikely that they can name a single muscle in the lowly thoracic spine. Our clinical experience over the years is that thoracic issues are seldom the primary stated reason people seek our services. Digging just a bit deeper however, it becomes clear that this area of the body is often quite restricted and is potentially the cause of other areas of concern, yet people are often unaware of just how much of a role the thoracic spine plays in their experience of pain.
For instance, when I am doing a lecture to demonstrate the effectiveness of PNMT to change range of motion, I almost always pick the thoracic spine to use as the demo. Why? Because I am most likely to find restrictions here, even more so than with the cervical spine. Those restrictions can be unilateral or bilateral and are often quite remarkable. If the same percentage of restrictions were true in the low back, neck or shoulder, people would be very aware of their existence. Ironically, as I write this I am on an airplane and I just watched a passenger struggle to exit her seat. Since she could not turn her thoracic spine, she had great difficulty extricating herself from the seat.
As this woman tried to leave her seat, her only available option was to try to turn from her lumbar spine, a process that did not go well. When you cannot rotate from above (the thoracic spine), you try to do that from below (the lumbar spine). Unfortunately, the lumbar spine has a very limited capacity to rotate, which she discovered in the process. With her hips fixed by the seat in the plane, and rotation very limited in the thoracic spine, her only option was to rotate her from her lumbar spine. Do that enough times and the likely result is low back pain. In terms of low back pain, there is ample evidence to suggest that restriction in the hips causes increased demand on the low back. In that case, restriction from an area below (the hips) causes increased demand on the area above it (the lumbar spine). it is very reasonable to assume the other direction (from above down) is also true.
In the same way, research supports the idea that treating restrictions in the thoracic will increase range of motion in the cervical spine. The takeaway lesson is that any restriction is not only a problem locally, but will create increased demand in related areas, often above or below it. Local treatment of only that affected area, such as low back pain, are likely to be unsuccessful or provide temporary relief. To change an outcome, you must change the context that created it.