The Erector Spinae group consists of: Iliocostalis, Longissimus and Spinalis.
Broad tendon from iliac crest, posterior surface of sacrum, sacro-iliac ligaments
Illiocostalis: superiorly to angles of lower ribs to transverse processes of cervical vertebrae
Longissimus: superiorly to ribs between tubercles and transverse processes in thoracic and cervical regions and to mastoid process
Spinalis : superiorly to spinous processess in upper thoracic region to cranium