CH: 9 Extended Review

Regions of the Vertebral Column

Vertebral Curves: Cervical and lumbar regions

•Convex anteriorly

•Lordotic

Lordosis

Excessive inward curvature of the spine, particularly in the lumbar region.

Vertebral Curves: Thoracic and sacral regions

•Concave anteriorly

•Kyphotic

Kyphosis

excessive posterior curvature of the spine, typically in the thoracic region.

Motions of the Vertebral Column

Vertebral column is triaxial and includes motions of the neck and trunk

Vertebral Column Motions: Flexion and Extension

occur within the sagittal plane about a frontal axis

Vertebral Column Motions: Lateral bending

occurs within the frontal plane about a sagittal axis

Vertebral Column Motions: Rotation

occurs within the transverse plane about a vertical axis.

Articulating Facets Orientation: Cervical spine

is within the frontal plane with lateral portion anterior to medial portion of facet. Motion in all three planes and axes

Articulating Facets Orientation: Thoracic spine

•Orientation of facets is within the frontal plane

•Motion limited by ribs

•Lateral bending

Articulating Facets Orientation: Lumbar spine

is within the sagittal plane with facets facing medial to lateral. Motion primarily allows flexion and extension.

Bony landmarks of Vertebrae

include the spinous process, transverse process, and vertebral body that provide attachment points for muscles and ligaments.

Intervertebral Foramen and Facet Joint

are openings between adjacent vertebrae allowing for the passage of spinal nerves and blood vessels, while facet joints provide articulation between vertebrae for movement and stability.

Thoracic Cage

is a structure formed by the ribs, sternum, and thoracic vertebrae that protects the thoracic organs and supports the upper body. It also plays a role in respiration.

Costovertebral and Costotransverse Joints

are joints formed between the ribs and the vertebrae, allowing for movement during breathing and providing stability to the thoracic cage.

Parts of a Vertebral Disk

consist of the annulus fibrosus and nucleus pulposus, which provide cushioning and absorb shock between vertebrae.

Vertebral Ligaments

are strong connective tissues that bind the vertebrae together, providing stability and support to the spine while allowing for a limited range of motion.

Vertebral muscles: Anterior: Trunk

Rectus abdominis

External oblique

Internal oblique

Transverse abdominis

Vertebral muscles: Lateral: Trunk

Quadratus lumborum

Vertebral muscles: Posterior: Trunk

Erector spinae group (3)

Transversospinalis group (3)

Interspinales

Intertransversarii

Posterior Trunk Muscles: Extension 

Spinalis (ES)

Interspinales

Posterior Trunk Muscles: Extension and lateral flexion

Longissimus (ES)

Intertransversarii

Iliocostalis (ES)

Posterior Trunk Muscles: Extension and rotation to same side

Splenius cervicis

Posterior Trunk Muscles: Extension and rotation to opposite side

Semispinalis (T)

Multifidus (T)

Rotatores (T)

Erector spinae group (3)

Spinalis, Longissimus, Iliocostalis 

Iliocostalis

lateral, will have attachment to rib

Longissimus

the intermediate muscle of the erector spinae group

Spinalis

medial, closest to the spine

Transversospinalis Muscle Group

a deeper set of muscles that lie beneath the erector spinae group, responsible for stabilizing and rotating the spine. Include multifidus, rotatores, and semispinalis.

Semispinalis

most superficial, only one that attaches to occiput

Multifidus

deep to semispinalis, sacrum to C4-C7, span 2-4 vertebrae

Rotatores

shortest and deepest, aid in stabilization of the spine along with multifidi, span only 1 vertebra

Interspinales Muscles

small muscles located between adjacent spinous processes, assisting in spinal extension.

Interspinales: origin

Spinous process of vertebra below

Interspinales: insertion

Spinous process of vertebra above

Interspinales: Action

Neck and trunk extension

Interspinales: innervation

Spinal nerves

Intertransversarii Muscles

Muscles located between the transverse processes of adjacent vertebrae, assisting in lateral flexion of the spine.

Intertransversarii: Origin

Transverse process of vertebra below

Intertransversarii: Insertion

Transverse process of vertebra above

Intertransversarii: Action

Neck and trunk lateral flexion to same side

Intertransversarii: innervation

Spinal nerves

Line of Pull

Determines muscle action for posterior trunk muscles

Rectus Abdominis Muscle

A long, flat muscle that extends vertically along the front of the abdomen, responsible for flexing the spine and stabilizing the pelvis.

Rectus Abdominis Muscle: Origin

Pubic crest

Rectus Abdominis Muscle: Insertion

Xiphoid process and costal cartilages of 5th through 7th seventh rib

Rectus Abdominis Muscle: Action

Trunk flexion: compression of abdomen

When pelvis stabilized: depresses ribs

Accessory muscle of respiration

Rectus Abdominis Muscle: Innervation

7th through 12th thoracic nerves

External Oblique Muscle

A muscle located on the lateral sides of the abdomen that aids in trunk rotation, flexion, and supports abdominal compression.

External Oblique Muscle: Origin

Lateral surface of lower eight (8) ribs

External Oblique Muscle: Insertion

Iliac crest, pubic tubercle, and linea alba via abdominal aponeurosis

External Oblique Muscle: Action

Bilaterally: trunk flexion; compression of abdomen

Unilaterally: trunk lateral flexion and rotation to opposite side

When pelvis stabilized: depresses ribs

Accessory muscle of respiration

External Oblique Muscle: Innervation 

8th through 12th intercostal, iliohypogastric, and ilioinguinal nerves

Internal Oblique Muscle

Located beneath the external oblique, the internal oblique muscle functions in trunk rotation, lateral flexion, and also aids in compressing the abdomen.

Internal Oblique Muscle: Origin

Inguinal ligament, iliac crest, thoracolumbar fascia

Internal Oblique Muscle: Insertion

8th through 12th ribs, linea alba via abdominal aponeurosis

Internal Oblique Muscle: Action

Bilaterally: trunk flexion; compression of abdomen

Unilaterally: lateral trunk flexion and rotation to same side (as the internal oblique)

When pelvis stabilized: depresses ribs

Accessory muscle of respiration

Internal Oblique Muscle: Innervation

8th through 12th intercostal, iliohypogastric, and ilioinguinal nerves

Transverse Abdominis Muscle

Deepest abdominal muscle, vital for core stability, with functions in compressing the abdomen.

Transverse Abdominis Muscle: Origin 

Inguinal ligament, iliac crest, thoracolumbar fascia; costal cartilages of the lower seven (7) ribs

Transverse Abdominis Muscle: insertion

Pubic crest, linea alba via abdominal aponeurosis

Transverse Abdominis Muscle: Action

Compression of abdomen

Accessory muscle of respiration

Transverse Abdominis Muscle: Innervation

7th through 12th intercostal, iliohypogastric, and ilioinguinal nerves

Relationships of Abdominal Muscles

Quadratus Lumborum Muscle

Stabilizes the pelvis and lumbar spine, assists in lateral flexion of the vertebral column.

Quadratus Lumborum Muscle: Origin 

Iliac crest

Quadratus Lumborum Muscle: Insertion

Twelfth rib; transverse processes of all five (5) lumbar vertebrae

Quadratus Lumborum Muscle: Action

Trunk lateral flexion to same side. Pelvic elevation on same side.

Quadratus Lumborum Muscle: Innervation

12th thoracic and 1st lumbar nerves

Diaphragm Muscle

Main muscle of respiration, separating the thoracic and abdominal cavities.

Diaphragm Muscle: origin

Xiphoid process, ribs, lumbar vertebrae

Diaphragm Muscle: Insertion

Central tendon

Diaphragm Muscle: Action

Inspiration

Diaphragm Muscle: Innervation

Phrenic nerve (C3, C4, C5)