Thoracic Spine

Thoracic Spine: what is it?

Twelve vertebrae between the neck and the lower back, each connected to a rib, form a section of spine that is inherently more stable and less mobile than the segments either side of it. The rib attachments limit how much it can bend forward and back but leave it with more rotation available than any other part of the spine. That division of labour matters: the neck above and the lumbar spine below are mobile in directions the thoracic spine is not, so when thoracic movement is lost, those neighbours take up the slack and are the ones that complain.

What it does and what depends on it

The thoracic spine rotates, extends and flexes, with rotation being its speciality. It also forms the back wall of the rib cage, so its position directly influences how the ribs move during breathing and where the shoulder blades sit.

Three things depend on adequate thoracic extension and rotation. The arm reaching fully overhead, because a rounded upper back tips the shoulder blades forward and reduces the room the arm has. The front rack position in cleans and front squats, for the same reason. And rotation in sport, where a stiff thoracic spine pushes the twisting demand into the lumbar spine, which has far less rotation available.

How to assess it quickly

Two tests take a minute and tell you most of what you need. For extension, have the client sit tall and lift both arms overhead; watch whether the ribs flare and the lower back arches to make up the range. For rotation, have them sit or kneel with the hips locked, hands behind the head, and rotate; compare left and right and watch how far the sternum turns.

Asymmetry matters more than absolute range. A client who rotates noticeably further one way, common in golfers, throwers and anyone with a one-sided job, is more informative than a client who is equally limited both ways.

How to train thoracic mobility

Mobility that lasts comes from control and load, not from a foam roller alone. A short daily dose of a few movements works better than a long weekly session, and finishing with a loaded position teaches the client to use the range they just gained.

Posture, stiffness and what to tell a client

Clients arrive convinced their rounded upper back is the cause of their pain, usually because someone told them so. The honest answer is more measured: resting posture varies enormously between healthy people and correlates weakly with pain. What is well supported is that having range available, and the strength to use it, makes movement easier and lets the shoulder and lower back do less compensating.

That is a better sell anyway. Frame thoracic work as buying back a position the client needs for overhead pressing, for rotating in sport, and for comfort in a long working day, rather than as fixing a posture that was never broken.