Sonographic evaluation of lumbar interlaminar space opening in a variety of patient body positions for optimal neuraxial anesthesia delivery.

•Of those we measured, sitting fetal provides the widest ILS.•Lateral decubitus and sitting hugging a ball also significantly increase the ILS.•Of those we measured, the above 3 positions are the most comfortable to assume.•A prospective study is needed to test the clinical significance for neuraxial anesthesia.