PRE LAB EXERCISE 48 Muscles of the Back Muscles of the back are layered and are

Pre lab exercise 48 muscles of the back muscles of

This preview shows page 13 - 17 out of 30 pages.

PRE-LAB EXERCISE 4.8: Muscles of the Back Muscles of the back are layered and are categorized into two major groups on each lateral side of the body: extrinsic back muscles and intrinsic back muscles . 59 © 2011 Shirley J. Wright, Ph.D.
Image of page 13

Subscribe to view the full document.

Extrinsic Back Muscles . Extrinsic muscles of the back include a superficial group and an intermediate group that function in controlling upper limb movements. Superficial extrinsic back muscles are the trapezius, latissimus dorsi, levator scapulae, rhomboid major and rhomboid minor . Posterior rami of spinal nerves innervate all of these muscles except the trapezius which is innervated by the spinal accessory nerve (cranial nerve XI). Search in Primal Pictures : .The screen should show an image of the vertebral column. Move the mouse over any region of the image to identify structures. Use the ◄► arrows to see the different muscle layers. Label the superficial extrinsic back muscles : trapezius, latissimus dorsi, rhomboid major, rhomboid minor, levator scapulae. In addition, label the thoracolumbar fascia. Intermediate Extrinsic Back Muscles . Lying deep to the superficial muscles are two intermediate extrinsic back muscles that are involved in respiration. They are innervated by anterior rami of spinal nerves and include the serratus posterior superior and serratus posterior inferior . 60 © 2011 Shirley J. Wright, Ph.D.
Image of page 14
Search in Primal Pictures: The screen should show an image of the vertebral column. Move the mouse over any region of the image to identify structures. Use the ◄► arrows to see the different muscle layers. Label the intermediate extrinsic back muscles : serratus posterior superior, serratus posterior inferior. In addition, label the thoracolumbar fascia which covers deep muscles. Intrinsic Back Muscles . Intrinsic muscles of the back lie deep to the intermediate extrinsic back muscles. They are innervated by posterior rami of spinal nerves and serve to control vertebral column movements and to maintain posture. Intrinsic back muscles are arranged in three layers: 61 © 2011 Shirley J. Wright, Ph.D.
Image of page 15

Subscribe to view the full document.

Superficial: spinotransversales or splenius muscles (splenius capitis, splenius cervicis) Intermediate: erector spinae – composed of 3 muscle groups (iliacostalis, longissimus and spinalis) each group has 3 muscles that lie in a groove between the spinous processes and angles of ribs. Deep: transversospinales (composed of semispinalis, multfidus, rotatores) and small segmental muscles (levatores costarum, interspinales, intertransversarii). Search in Primal Pictures : ? embeddedcode=5953DB .The screen should show an image of the vertebral column. Move the mouse over any region of the image to identify structures. Use the ◄► arrows to see the different muscle layers.
Image of page 16
Image of page 17
  • Spring '11
  • Masthay
  • Vertebra, Bones of the torso

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern

Ask Expert Tutors You can ask 0 bonus questions You can ask 0 questions (0 expire soon) You can ask 0 questions (will expire )
Answers in as fast as 15 minutes