why putting a pillow under your knees when you sleep helps with back pain

Question

why putting a pillow under your knees when you sleep helps with back pain

In: 11

Answer 1

Massage therapist here, and side sleeper.

Under knees when supine (laying on the spine) shortens any muscles pulling on the pelvic girdle and allows tight lower back muscles to lengthen.

For side lying, a pillow raising the upper knee will ease the hip flexors, glutes, and sciatic nerve entrapment sites.

Ease means less pain.