Spine & Thorax - BBL

  1. Topographical Views

    1. Vertebrae- an animal that has a spinal column

    2. An insect or mollusk has now spinal column

    3. Quadrupeds- animals that walk on four legs

    4. Bipeds- animals that walk on two legs

      1. Ex.) Humans

    5. Pneumatized - air filled

      1. Happens in vertebrae, sternum and pelvis of bird

  2. Bones of the Spine & Thorax

    1. Vertebral column (spine)- consists of 25 bones

      1. 7 cervical of the neck

      2. 12 thoracic of the thorax

      3. 5 lumbar in lower back

      4. Sacrum & coccyx  are fused vertebrae

    2. Cervical vertebrae are the most mobile and accessible

    3. Thoracic vertebrae articulate with the 12 pairs of ribs

      1. Minimal movement

      2. Help stabilize the thoracic area and protect internal organs

    4. Lumbar vertebrae

      1. Designed to support the weight of the upper body

    5. Thorax- includes sternum & rib cage

    6. Rib cage- consists of coastal cartilage & 12 pairs of ribs

      1. Costal cartilage is identical in shape & size to the ribs and serves as a bridge between them and the sternum

      2. Ribs 1-7 - true ribs

        1. Attach to the sternum

      3. Ribs 8-12 - false ribs

        1. They attach indirectly to the sternum by means of the coastal cartilage

      4. Ribs 11-12 - floating ribs

        1. Do not attach to sternum or costal cartilage

  3. Overview : Bony Landmark Trails

    1. Vertebral column has 4 natural curvatures

      1. Cervical & lumbar regions bend anteriorly to form lordotic curves

      2. Thoracic & sacral sections bow posteriorly to form kyphotic curves

      3. Scoliosis- abnormal lateral curvature

      4. At birth, the spine has a single kyphotic curvature

      5. Cervical lordosis- develops when an infant beings to hold his head erect

      6. Intervertebral disks cushion shock

        1. Composed of a tough outer layer, annulus fibrosus

        2. Liquid center nucleus pulposus

          1. Some of the water is squeezed out in the course of the day

          2. You wake up in the morning half an inch taller because water is reabsorbed

    2. Spinous Processes of the Vertebrae

      1. Spinous process is a vertebrae's posterior projection

      2. Attachment sites for layers of muscles, ligaments and fasciae

      3. The atlas (C-1) only vertebrae that does not have a spinous process

    3. Transverse processes of the Cervicals

      1. TVPs serve as attachment sites for various muscles, including the scalenes and levator scapulae

      2. Brachial plexus, a large group of nerves that innervates the arm, exits between the TVPs

    4. Cervical Lamina Groove

      1. Lamina groove- troughlike space between the spinous and transverse processes of the vertebrae

      2. C-6 has a large anterior tubercle called carotid tubercle

        1. Cartoid artery passes laterally

    5. Sternum

      1. Jugular notch- between the sternal heads of the clavicles

      2. Manubrium- superior portion of the sternum, articulates with the clavicles, the first rib, and the second rib

      3. Body of the sternum- located inferior to the manubrium & forms the major portion of the sternum

      4. Sternal angle- junction between the manubrium and body of the sternum

      5. Xiphoid process- bottom of the sternum

        1. Attachment site for the rectus sheath

    6. Ribs & Coastal Cartilage

      1. Ribs- articulate posteriorly with the thoracic vertebrae and then curve around the thorax to the anterior chest

      2. Costal cartilage- attaches ribs to sternum

        1. 6 or 7 branches

    7. First Rib

      1. ribs are designed to expand in three directions: inhalation, lateral & superior