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
What is the Origin of Longissimus?
Common Tendinous Origin
Largest of the 3. Can be Divided into 3 Parts – Thoracic, Cervicis and Capitis.
What is the Attachment of Longissimus?
Lower Ribs, the Transverse Processes of C2-T12 and the Mastoid Process of the Skull.
What is the Action of Longissimus?
Acts Unilaterally to Laterally Flex the Vertebral Column. Acts Bilaterally to Extend the Vertebral Column and the Head.
What is the Innervation of Longissimus?
Posterior Rami of the Spinal Nerves
What is the Origin of Spinalis?
Common Tendinous Origin
What is the Attachment of Spinalis?
Spinous Processes of C2, T1-T8 and the Occipital Bone of the Skull.
What is the Action of Spinalis?
Acts Unilaterally to Laterally Flex the Vertebral Column. Acts Bilaterally to Extend the Vertebral Column and the Head.
What is the Innervation of Spinalis?
Posterior Rami of the Spinal Nerves
What are the Main Deep Muscles of the Back?
Semispinalis (Most Superficial)
Multifidus (Deep to Semispinalis)
Rotatores (Most Common in Thoracic Region)
What is the Origin of Semispinalis?
Transverse Processes of C4-T10. The Fibres Ascend 4-6 Vertebral Segments.
What is the Attachment of Semispinalis?
Spinous Processes of C2-T4 and the Occipital Bone of the Skull
What is the Action of Semispinalis?
Extends and Contralaterally Rotates the Head and Vertebral Column
What is the Innervation of Semispinalis?
Posterior Rami of the Spinal Nerves
What is the Origin of Multifidus?
Sacrum, Posterior Iliac Spine, Common Tendinous Origin of the Erector Spinae, Mammillary Processes of the Lumbar Vertebrae, Transverse Processes of T1-T3 and Articular Processes of C4-C7.
What is the Attachment of Multifidus?
The Fibres Ascend 2 Vertebral Levels then Attach to the Spinous Processes of the Vertebrae.
What is the Action of Multifidus?
Stabilises the Vertebral Column
What is the Innervation of Multifidus?
Posterior Rami of the Spinal Nerves
What is the Origin of Rotatores?
Vertebral Transverse Processes
What is the Attachment of Rotatores?
Lamina and Spinous Processes of the Immediately Superior Vertebrae
What is the Action of Rotatores?
Stabilises the Vertebral Column, and Has a Proprioception Function.
What is the Innervation of Rotatores?
Posterior Rami of the Spinal Nerves
What are the Minor Deep Muscles of the Back?
Interspinales
Intertranversari
Levatores Costarum
Attachments of Interspinales
Span between Adjacent Spinous Processes
Action of Interspinales
Acts to Stabilise the Vertebral Column
Attachments of Intertranversari
Spans between Adjacent Transverse Processes
Action of Intertranversari
Acts to Stabilise the Vertebral Column
Attachments of Levatores Costarum
Originates form the Transverse Processes of C7-T11 and Attaches to the Rib Immediately Below.
Action of Levatores Costarum
Acts to Elevate the Ribs.