Most practitioners who call their treatments “craniosacral therapy” are generally working through a biomechanical understanding. The motion in the bones, membranes, and cerebrospinal fluid is the focus. The practitioner might directly or indirectly work with the subtle movement between bony surfaces or use the tide-like motion in the cerebrospinal fluid to increase the body’s healing potential. A biomechanical craniosacral therapist will generally be looking for a rhythm in the body that is more superficial and faster--one that is an adaptive response of the autonomic nervous system to stress. They will spend more time working directly with the bones of the cranium.
In biodynamic craniosacral therapy, we work with the entire fluid body in our field of awareness. As an adult, we are a minimum of 75% water, and even the living bones, organs, and membranes consist of fluids. We use the subtle rhythmic motion in the fluids to amplify the healing ability of the body. What Sutherland called "The Breath of Life" is now called the "Primary Respiration System" in biodynamic craniosacral therapy. In biodynamic craniosacral work, the faster rhythms found in the bones, membranes, and cerebrospinal fluid are considered to be an expression of trauma and stress in the body. We tap into the manifestation of a slower fluid rhythm as a way to go “under the wire”, so to speak. We go deeper than the stress/trauma pattern to a place of slowness, stillness, and wholeness--a place where the body has the transmutative ability to heal.