Intrinsic Muscles of the Back Flashcards
How many Muscles make up the Superficial (Spinotransversales) Layer?
2 - Splenius Captius
Splenius Cervicis
What is the Origin of Splenius Capitus?
Lower Aspect of Ligamentum Nuchae and the Spinous Processes of C7-T3/4 Vertebrae
What is the Attachment of Splenius Capitus?
Mastoid Process and the Occipital Bone of the Skull
What is the Action of Splenius Capitus?
Rotate head to Same Side.
What is the Innveration of Splenius Capitus?
Posterior Rami of Spinal Nerves C3 and C4
What is the Origin of Splenius Cervicis?
Spinous Processes of T3-T6 Vertebrae
What is the Attachment of Splenius Cervicis?
Transverse Processes of C1-C3/4
What is the Action of Splenius Cervicis?
Rotate Head to the Same Side.
What is the Innervation of Splenius Cervicis?
Posterior Rami of the Lower Cervical Spinal Nerves
What is the Joint Action of Splenius Capitus and Splenius Cervicis?
Extend the Head and Neck
How many Muscles make up the Intermediate Layer?
3 - Iliocostalis (Most Lateral)
Longissimus
Spinalis (Most Medial)
What do the Intermediate Muscles Collectively Form?
Erector Spinae
Where is the Erector Spinae Located in Relation to the Spinal Column
Posteriolaterally, between the Vertebral Spinous Processes and the Costal Angle of the Ribs
What do the Intermediate Muscles have in Common?
Common Tedinous Origin Arising from: • Lumbar and Thoracic Vertebrae • Sacrum • Posterior aspect of the Iliac Crest • Sacroiliac and Supraspinous Ligaments
What is the Origin of Iliocostalis?
Common Tendinous Origin
What is the Attachment of Iliocostalis?
Costal Angle of the Ribs and the Cervical Spinous Processes
What is the Action of Iliocostalis?
Acts Unilaterally to Laterally Flex the Vertebral Column. Acts Bilaterally to Extend the Vertebral Column and the Head.
What is the Innervation of Iliocostalis?
Posterior Rami of the Spinal Nerves