Anatomy

Origin

Longissimus Capitis - Trachelomastoid Muscle: Transverse processes of upper five thoracic vertebrae (T1–T5), articular processes of lower three cervical vertebrae (C5–C7) Longissimus Cervicis - Transversalis Cervicis: Transverse processes of upper four or five thoracic vertebrae (T1–T5) Longissimus Thoracis - Longissimus Lumborum: Medial and lateral sacral crests, spinous processes and supraspinal ligament of lumbar and eleventh and twelfth thoracic vertebrae, and medial part of iliac crests

Insertion

Longissimus Capitis - Trachelomastoid Muscle: Posterior part of mastoid process of temporal bone Longissimus Cervicis - Transversalis Cervicis: Transverse processes of second through sixth cervical vertebrae (C2–C6) Longissimus Thoracis - Longissimus Lumborum: Transverse processes of all thoracic vertebrae, between tubercles and angles of lower nine or ten ribs

Nerve

Longissimus Capitis - Trachelomastoid Muscle: is inervate by Dorsal primary divisions of middle and lower cervical nerves. Longissimus Cervicis - Transversalis Cervicis and Longissimus Thoracis - Longissimus Lumborum: Dorsal primary divisions of spinal nerves.

Actions

Longissimus Capitis - Trachelomastoid Muscle: Extends (bilateral contraction) and rotates (unilateral contraction) head Longissimus Cervicis - Transversalis Cervicis: Extension (bilateral contraction), lateral flexion (unilateral contraction) of vertebral column Longissimus Thoracis - Longissimus Lumborum: Extension, lateral flexion of vertebral column (in unilateral contraction), rotates ribs for forceful inspiration