This extra dense foam stretches spinal muscles and mobilizes the spine during warm up exercises prior to treatment.
Thoracic spine extension foam roller.
Thoracic spine foam rolling exercising with a foam roller can help relax tight muscles and improve flexibility and symmetry.
I personally would have no problem with a patient telling me that they use a foam roller on their thoracic spine.
Rolling back and forth horizontally relaxing with it lengthwise along their spine to open the chest or even some typical extensions mid thoracic.
Thankfully thoracic mobility can be easily maintained and improved using a foam roller and the thoracic spine extension exercise as described below.
Bend your knees and place your feet on the floor.
How to do it.
Kudos to them they took some initial to work on their mobility.
Lie on your back.