hindbrain to wall is 2.5 cm. This demonstrated a difference about
9.0 (11.52.5) cm from head to bed surface in crown plane and in
sagittal plane. That means when lateral sleep, a pillow height of
11.5 cm is needed for compensation to maintain spine in natural
position and when supine sleep, a pillow height of 2.5 cm is needed
for compensation to maintain spine in natural position. The difference
of pillow height in lateral and supine position is as many as
9.0 cm. The length from neck to wall is 5.4 cm and from hindbrain
to wall is 2.5 cm, so an additional neck support with 2.9 (5.42.5)
cm is needed for compensation in supine position.