Diagnostics Lumbar Spine Sitting Position

Let the person sit relaxed in an upright position, with the backs of the knees connected to the treatment table.
Palpate the Spina Iliaca Posterior Superior and the Cristae Iliaca with utmost accuracy. Approach the Spina Iliaca Posterior Superior from a caudal direction, paying careful attention to even the slightest differences in height.

Ask the person to perform a lordosis (extension), and observe whether the difference in height between the Spina Iliaca Posterior Superior and Cristae Iliaca increases or decreases. Similarly, have the person adopt a kyphosis (flexion) and note any changes in the height difference of the Spina Iliaca Posterior Superior and Crista Iliacae.
The identification of a difference in height between the Spina Iliaca Posterior Superior and Cristae Iliaca indicates a lateral flexion in the Lumbar Spine. Specifically, if the right Spina Iliaca Posterior Superior is higher, it corresponds to a lateral flexion to the right, and vice versa.

If the height difference increases during lordosis (extension), it suggests that the lateral flexion is more pronounced in an extended position of the spine. This implies a preferred position of the Lumbar Spine in either a B (extension – right lateral flexion – right rotation) or a D (extension – left lateral flexion – left rotation). Conversely, if the height difference is more apparent during kyphosis (flexion), the preferred position would be an A (flexion – right lateral flexion – left rotation) or a C (flexion – left lateral flexion – right rotation). If two parameters are identified, the third becomes evident.

Guide the person in performing a lateral flexion by lifting one side of the pelvis. Note that as one side is lifted, the Lumbar Spine shifts in the opposite direction, and the centre of gravity also moves accordingly.

To prevent the Thoracic Spine from mimicking the movement during lateral flexion, apply slight pressure against the opposite shoulder while lifting one side of the pelvis. This pressure does not immobilize the Thoracic Spine but lets the Lumbar Spine to initiate the movement, providing a clearer understanding of the possibilities of lateral flexion in the lumbar spine.

For a fixed lateral flexion, place a small elevation under one side of the pelvis, specifically under the Tuberositas Ischiadicum. Experiment with flexion or extension, combining these positions with rotations to identify the best-preferred position; in which position (kyphosis / lordosis) is a rotation better or worse performed.