The Thoracolumbar Junction - where breath meets stability
The Thoracolumbar Junction. Don’t ask me why, but it’s my favourite phrase in anatomy!
It’s a quiet crossroads in the body where breath, posture, and stability meet. It sits on your back where the lower ribs end and the lumbar spine begins. Though small, it plays a powerful role in how we move and how supported we feel.
When this area stiffens, as it often does through sitting or bracing, the breath can’t fully expand, and the deep stabilising muscles — the diaphragm, multifidus, and transverse abdominis — lose their natural rhythm. The result isn’t just physical tightness; it’s a kind of inner holding that echoes how we move through the world — pushing, protecting, controlling.
A small but powerful meeting point
Anatomically, the thoracolumbar junction (TLJ) is the transition between the thoracic spine (T11–T12) and the lumbar spine (L1–L2) — the point where the rib cage ends and the lower back begins.
The vertebrae here are relatively stable, but the region itself is a functional crossroad, where breath, spinal control, and load transfer all converge.
Although the diaphragm doesn’t attach directly to the TLJ, its deep fibres (the crura) connect to the front of the upper lumbar vertebrae. These fibres blend with fascia that continues into the psoas and thoracolumbar fascia, linking the diaphragm above to the deep spinal stabilisers and pelvic structures below.
This means that every breath subtly influences this junction. When we breathe well, the diaphragm descends and the lower ribs expand, transmitting gentle pressure through the fascia into the core — helping the spine stabilise from within. When we brace, flare the ribs, or hold the breath, (or have the shallow breath pattern of anxiety) that natural support system is disrupted.
The breath–core connection (and why it matters on the mat)
Many people think of core control as “holding in” or “tightening.” In reality, the core is a dynamic pressure system, shaped by breath.
As you inhale, the diaphragm descends and the ribs expand. This expansion subtly lengthens the spine and gently activates the deep core — particularly when the thoracolumbar junction is free to move.
As you exhale, the diaphragm rises and the deep abdominals respond, supporting the spine without force.
In class this week, we’ve been exploring how connecting the back of the ribs and the thoracolumbar area to the mat changes everything. When the legs lift or extend, there’s a natural tendency for the ribs to flare and the lower back to lift away. That small movement shifts the work into the hip flexors, reducing the engagement of the deep stabilisers.
But when you keep gentle contact through the back of the ribs and allow the breath to expand sideways and back — rather than up into the chest — you invite a deep internal support.
The diaphragm, pelvic floor, multifidus, and transverse abdominis coordinate like the sides of a cylinder, holding the trunk steady from the inside out. The movement feels more integrated, but also more demanding — because now the right muscles are doing their job.
From rigidity to rhythm
Strength and stability don’t come from rigidity — they come from rhythm. The thoracolumbar junction is designed to move with the breath, not hold against it.
Try this simple practice:
Lie on your back with your knees bent and hands around your lower ribs.
As you inhale, feel the breath widen into your hands — not just at the front, but into the back and sides.
As you exhale, allow the ribs to soften and the spine to settle without forcing it flat.
Notice the subtle expansion and recoil — the quiet rhythm of support.
This small awareness restores mobility and connection to the thoracolumbar region, helping your body rediscover a strength that feels calm and sustainable.
A rhythm worth trusting
The thoracolumbar junction reminds us that the strongest structures are those that can respond.
When we learn to stabilise through breath, not bracing — to connect, not clamp — we build the kind of control that lasts well beyond the mat.
If you want to move with more awareness, then come and explore my Reset Membership - your wellness Subscription with Pilates at the core. Available through my website below.
References
Bordoni, B. and Zanier, E. (2013) ‘Anatomic connections of the diaphragm: influence of respiration on the body system’, Journal of Multidisciplinary Healthcare, 6, pp. 281–291.
Fornari, M., Chillemi, G., Ottaviani, P. and Barra, F. (2025) ‘Anatomy of the diaphragmatic crura and other paraspinal structures: a cadaveric and radiological study’, European Spine Journal. Available at: https://doi.org/10.1007/s00586-025-08716-0
