Myofascial Spiral Line (as described by Tom Myers)
We can continue to follow from the feet through a network of support that wraps round the whole of the body. The spiral line is deeply interconnected and interrelated with each of the myofascial meridians and is designed to steady the legs and trunk and counterbalance any rotational action. It connects the foot arch, through the pelvic angle to maintain balance in all planes of movement. Counterbalancing at the hip and core level is often interrelated with the deep hip flexors and the psoasic matrix.
Because the continuity at the pelvis is mechanical, the two portions are capable of functioning separately or collectively. The spiral lines often reflect deeper spinal twists, as well as postural and rotational twists created through usage and dominance patterns such as handedness.
A spiral, significantly, is different from arotation as it inherently contains an element of extension along its axis.