Which of the following is NOT a common spinal misalignment?

Flatback is considered a postural condition rather than a spinal misalignment in the same way that lordosis, kyphosis, and scoliosis are. Lordosis refers to an excessive inward curvature of the lumbar spine, kyphosis is an excessive outward curvature of the thoracic spine, and scoliosis involves a lateral curvature of the spine. Each of these conditions represents specific deviations from normal spinal alignment, affecting overall posture and potentially leading to discomfort or functional difficulties.

Flatback, while it can indicate postural issues, typically refers to a reduction or loss of the normal lumbar lordosis, resulting in a more flattened spinal appearance. It does not denote a specific curvature pattern like the other conditions do. Therefore, among the choices, flatback stands out as not fitting the definition typically applied to common spinal misalignments.