muscle | origin | insertion | action | nerve |
Longissimus capitis | transverse processes of superior 4 thoracic vertebrae and articular processes of inferior 4 cervical vertebrae | mastoid process of temporal bone | acting together, both longissimus capitis muscles extend head, singly, rotate head to same side as contracting muscle | middle and inferior cervical spinal nerves |
Longissimus cervicus | transverse processes of 4th and 5th thoracic vertebrae | transverse processes of 2nd to 6th cervical vertebrae | acting together, longissimus cervicus and both longissimus thoracis muscles extend vertebral column of their region, acting singly, laterally flex vertebral column of their region | cervical and superior thoracic spinal nerves |
Longissimus Thoracis | transverse processes of lumbar vertebrae | transverse processes of all thoracic and superior lumbar vertebrae and 9th and 10th ribs | acting together, longissimus cervicus and both longissimus thoracis muscles extend vertebral column of their region, acting singly, laterally flex vertebral column of their region | thoracic and lumbar spinal nerves |
Gracilis | body and iferior ramus of pubis | medial surface of body of tibia | adducts thigh at hip, medially rotates thigh, and flexes leg at knee | Obturator nerve |
Tibialis posterior | tibia, bibula, and interosseous membrane | 2nd, 3rd and 4th metatarsals, navicular, all 3 cuneiforms, and cuboid | plantar flexes foot at ankle, inverts foot at intertarsal joints | tibial nerve |