Incorporating Fibers with my Clay Figure

I am starting to work with fibers for this project for our Houseguest Show.  The intention with this part of the project is to connect the pelvis ceramic parts and the figure ceramic piece together with yarn fiber and tension.  The yarn will act as internal muscle and tissue that connect these body parts together, which are also the root of the pain in my personal experience.  

This diagram to the left is the muscles that I am focused on which literally attach the ribcage to the pelvis and are prominent in movement and function of the body.  Here is an excerpt from a book called The Vital Psoas:

"Located deep within the anterior hip joint and lower spine, the psoas major (usually just referred to as the psoas) is critical for optimal postural alignment, movement, and overall well being. The psoas is the only muscle in the human organism that connects the upper body to the lower body, and its importance extends to the nerve complex and energy systems."
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