Muscle Origin Insertion Action
Semispinalis Thoracis Transverse process of T6-T10 Spinous process of T1-T4;C6, C7 Unilateral:rotates spine in opposite direction; Bilateral: extends spine
Semispinalis Cervicis Transverse process of T1-T6 Spinous process of C2-C5 Unilateral:lateral Flexion; rotation to opposite side; Bilateral: Extension
Semispinalis Capitis Transverse process of C7; T1-T6; Articular process of C4-C6 Between suuperior and inferior lines of occipital bones Unilateral: lateral flexion rotation in opposite direction; Bilateral:extension
Iliocostalis Lumborum Anterior surface of tendon attached to sacrum; Spinous process of L1-L5; T11-T12/ medial part of iliac crest Inferior borders of lower 6-7 ribs (T4 or T5-T10) Unilateral: lateral flexion; Bilateral:
Iliocostalis Thoracis Superior borders of lower 6-7 ribs Upper 6-7 ribs; transverse process of C7 Unilateral: lateral flexion of spine; Bilateral:extension
Iliocostalis Cervicis Superior border of T3-T6 Transverse processes of C4-C6 Unilateral:Lateral flexion; Bilateral: Extension of spine
Longissiumus Cervicis Transverse process of T1-T5 Transverse process of C2-C6 Unilateral:Lateral flexion of neck; Bilateral:Extension
Longissimus capitis Transverse process of T1-T5, articular process of C4-C7 Posterior part of mastoid process Unilateral: Lateral flexion of head; rotation to same side; Bilateral Extends head
Spinalis Thoracis Spinous process of L1-L2; T11-T12 Spinous process of T4-T8 Unilateral:Lateral flexion; Bilateral:Extension
Spinalis Cervicis Spinous process of C7, T1-T2 Spinous process of C2-C4 Unilateral: lateral flexion; Bilateral: extension
Splenius Cervicis Spinous process of T3-T6 Transverse process of C1-C4 Unilateral: lateral flexion; rotation to same side; Bilatera: Extends neck and head
Splenius capitis Spinous process of C7-T3 Mastoid proceses Unilateral: Laterally flexes neck, rotation to same direction; Bilateral: extends head and neck
Quadratus Lumborum (QL) Posterior part of iliac crest Inferior border of twelfth rib; transverse process of L1-L4 Unilateral: Lateral flexion of lumbar vertebrae; diaphragm in inspiration