In the Reciprocal Tension Membrane concept, the sacral base moves anteriorly with cranial extension. Which cranial motion is this associated with?

• A. Cranial extension
• B. Cranial flexion
• C. Cranial rotation
• D. Cranial translation

Answer: (A)

In the Reciprocal Tension Membrane framework, the dural membranes form a continuous link from the skull to the sacrum, so motion at one end influences the other. When the cranium extends, the tension pattern shifts so the sacral base moves anteriorly. This creates the linked, opposite pattern that defines the primary respiratory mechanism: cranial extension corresponds to anterior sacral movement. Conversely, cranial flexion would be associated with posterior sacral base motion. Rotation and translation are not the primary pair described for this specific craniosacral relationship.