INTRODUCTIOThe reason for physical rotation compression on vertebral artery atG is that there isn t intervertebral joints between at-lantoepistrophic transverse processes. At rear of vertebral artery be-tween atlantoepistrophic transverse processes is covered by inferioroblique muscle which originates from spinous process of axis andended at transverse process of atlas. When head rotates towardsright, inferior oblique muscle of left side will rotate towards left andforward which muscle belly enters interspace of first transverse pro-cess and compress vertebral artery. At the same time, right vertebralartery enters rear of atlantoepistrophic spinous process and isn tcompressed that ensures blood supply of basal artery. When head andneck resume neutral position, inferior obhque muscle is replaced andcompression on left vertebral artery is decompressed, so inferioroblique muscle is the anatomic base of physical compression onvertebral compression