The thoracic spine (T-spine) is often a site for postural dysfunction. Chronic sitting can produce excessive kyphosis and lead to decreased capability to move well in the frontal and transverse planes.
Type 1 thoracic motion is characterized by spinal rotation and lateral flexion in opposite directions, typically exhibited from T-6 to T-12. When this motion is impaired, poor force transmission can lead to egregious stress through the low back and neck.
The thoracic spine also displays Type 2 motion, which is characterized by spinal rotation and lateral flexion in the same direction. This movement is typically exhibited from T-1 to T-5, and is essential for swinging sports and most activities of daily living.