[TA] intermediate layer of deepest (transversospinales) muscles of back; origin, from the sacrum, sacroiliac ligament, mammillary processes of the lumbar vertebrae (multifidus lumborum [TA], SYN musculus multifidus lumborum [TA]), transverse processes of thoracic vertebrae (multifidus thoracis [TA], SYN musculus multifidus thoracis [TA], and articular processes of last four cervical vertebrae (multifidus cervicis [TA], SYN musculus multifidus cervicis/colli [TA]); insertion, into the spinous processes of all the vertebrae up to and including the axis; action, rotates vertebral column; nerve supply, posterior rami of spinal nerves. SYN: musculus multifidus (cervicis/colli, lumborum et thoracis) [TA], musculus multifidus spinae.