Neck & Trunk

Ligamentum Flavum

Connects adjacent laminae anteriorly.

Median Atlantoaxial Joint

Consists of a synovial articulation between the odontoid process (dens) of the axis and the anterior arch of the atlas anteriorly and the transverse ligament posteriorly.

Vertebral Notches (Vertebrae)

Depressions located on the superior and inferior surfaces of the pedicle, and are so named.

Vertebrae

Differ in size and shape but generally have the same layout.

Skull

Divided into bones of the cranium. The bony structure of the head, containing and protecting the brain and facial bones.

Why does the thoracic spine has much less motion than the cervical and lumbar regions?

Due to its attachments to the rib cage. The shape of the vertebral bodies and the length of the spinous processes also limit thoracic motion.

What are the posterior muscles of the neck?

Erector spinae group (3), splenius capitis, splenius cervicis, sub occipital group (4)

What are the posterior muscles of the trunk?

Erector spinae group (3), transversospinalis group (3), interspinales, intertransversarii

Cervical Protraction

Extending the head on C1 and flexing the neck (C2-C7).

Supraspinal Ligament

Extends from the 7th cervical vertebra distally to the sacrum posteriorly along the tips of the spinous processes.

What are the main motions of the atlanto-occipital joint?

Flexion and extension (nodding your head "yes").

What are the movements of the vertebral column?

Flexion, extension, hyperextension; lateral bending (side bending), rotation.

Transverse Process (Vertebrae)

Formed at the union of the lamina and pedicle, the lateral projections of the arch to which muscles and ligaments attach.

Atlanto-occipital Joint

Formed by the condyles of the occiput that articulate with the superior articular processes of the atlas. Supports the weight of the head.

Temporal Bone

Forms part of the base and lateral inferior sides of the cranium.

Lateral bending (side bending) occurs in the ___ plane around a ___ axis.

Frontal plane, sagittal axis

Thoracic orientation occurs in the ___ plane and contains the motions of ___ & ___.

Frontal plane; rotation and lateral bending.

Transverse Foramen

Holes of openings in the transverse process of each of the cervical vertebra through which the vertebral artery passes.

What takes the place of the supraspinal and interspinal ligaments in the cervical region?

Ligamentum Nuchae (nuchal ligament)

Occipital Condyles

Located lateral to the foramen magnum on the occiput; provides articulation with the atlas (C1).

What is the most injured region of the human body? Why?

Lumbar spine because it absorbs the majority of our body weight plus any weight we carry.

Cervical orientation is ___ and has a great deal of flexion/extension, rotation, and lateral bending.

Oblique

Cervical sprains

Occurs when the head suddenly and violently hyperextends and then flexes. Whiplash is the layman's term for this condition.

Herniated disks

Occurs when there is a weakness or degeneration of the annulus fibrosis (outer layer).

Vertebral Foramen (Vertebrae)

Opening formed by the joining of the body and neural arch though which the spinal cord passes.

Intervertebral Foramen (Vertebrae)

Opening formed by the superior vertebral notch of the vertebra below and the inferior vertebral notch of the vertebra above.

Foramen Magnum

Opening in the occipital bone through which the spinal cord enters the cranium.

Describe the spinal column:

Provides pivot point for motion and support of the head at cervical region. Multijointed rod that provides movement, also provides shock absorption and transmission.

Nucleus Pulposus (Intervertebral Disk)

Pulpy, gelatinous substance with a high water content in the center of the disk. At birth, it is approximately 80% water, decreasing to less than 70% at 60 years of age. This is partially why an individual loses height with advanced age.

What is the lateral muscle of the trunk?

Quadratus lumborum

What are the anterior muscles of the trunk?

Rectus abdominis, external oblique, internal oblique, transverse abdominis

Name the muscles of the trunk:

Rectus abdominis, external oblique, internal oblique, transverse abdominis, erector spinae, transversospinalis, interspinales, intertransversarii, quadratus lumborum

Basilar Area

Refers to the base, or inferior, portion of the occiput.

Atlantoaxial Joints

Two and are articulations between the atlas and axis.

Compression fractures

Typically result in the collapse of the anterior (body) portion of the vertebrae. Usually caused by trauma in the lumbar region or by osteoporosis in the thoracic region.

Fractures with dislocation (Unstable fractures)

Usually result in spinal cord injury and paralysis.

Spondylolisthesis

Usually results from a fracture, or giving way, of a defective pars interarticularis. One vertebra slips forward in relation to an adjacent vertebra, usually L5 slipping anterior on S1.

What is the action of the quadrates lumborum muscle?

Trunk lateral bending

What is the action of the transverse abdominis muscle?

Compression of abdomen

Demifact

"Half"; located laterally on the superior and inferior edges of the vertebral body where ribs articulate with thoracic vertebrae. Depending on rib placement on the body, it may be found on these edges.

The skull is made up of ___ separate bones and is considered to be the skeleton of the head.

21

Ankylosing spondylitis

A chronic inflammation of the vertebral column and sacroiliac joints, leads to fusion. A progressive rheumatic disease; over time, it can lead to a total loss of spinal mobility.

Tectorial Membrane

A continuation of the posterior longitudinal ligament and serves as a sling to support the spinal cord as it enters the vertebral column.

Torticollis

A deformity of the neck in which the person's head is laterally bent to one side and rotated toward the other side. Also known as wry (twisted) neck.

Spondylosis (spinal osteoarthritis)

A degenerative disorder of vertebral structure and function. May result from bony spurs, thickening of ligaments, and decreased disk height that results from reduced water content of the nucleus pulpous, a normal part of the aging process.

Osteoporosis

A disease in which bone is removed faster than it can be laid down. This results in decreased bone mass and density, making the bone more prone to fracture. Common sites for fracture are the hip, the thoracic vertebral column, and the wrist.

Hangman's fracture

A fracture involving C2 and typically occurs when there is a forceful, sudden hyperextension of the head.

Thoracic outlet syndrome

A general term referring to compression of the neurovascular structures (brachial plexus and subclavian artery and vein) that run from the neck to the axilla.

Atlantoaxial Joint

A joint in the upper part of the neck between the C1 & C2.

Spinal sternosis

A narrowing of the vertebral canal that houses the spinal cord.

Facet

A small, smooth, flat surface on a bone. Found on thoracic vertebrae at the point of contact with a rib. Also called costal facts, they are located superiorly and inferiorly on the sides of the vertebral bodies and on the transverse process of thoracic vertebrae. It is here that the ribs articulate with the vertebrae.

Spondyloysis

A vertebral defect in the pars interarticularis (the part of the lamina between the superior and inferior articular processes). Most commonly seen in L5 and less commonly in L4.

Occipital Bone

Also called the occiput; it forms the posterior inferior part of the cranium.

Dens

Also called the odontoid process; large vertical projection located anteriorly on the axis. Cervical rotation occurs through its articulation with the atlas.

Neural Arch (Vertebrae)

Also called the vertebral arch, it is the posterior portion of the vertebra with many different parts.

C7

Also known as vertebra prominens because of its long and prominent spinous process. It resembles a thoracic vertebra and can be easily palpated with the neck in flexion.

Flat back

An abnormally decreased lumbar curve.

Lordosis

An abnormally increased curve of the lumbar spine. Swayback.

Kyphosis

An abnormally increased thoracic curve.

Anterior Atlanto-Occipital Membrane

An extension of the anterior longitudinal ligament, which is somewhat thin superiorly.

Where is the center of gravity located in the body?

Anterior to the second sacral vertebra.

Scoliosis

Any amount of lateral curve.

Atlanto-occipital Joint

Articulation between the head and C1 (atlas).

Body (Vertebrae)

Being primarily a cylindrical mass of cancellous bone, it is the anterior portion of the vertebra and the major weight-bearing structure. It is not present in the atlas (C1). Between C3 & S1, bodies become progressively larger, bearing progressively more weight.

Where does most movement of the lumbar spine occur?

Between L4 and L5 and between L5 and S1; most disk herniations occur at these two levels.

Lateral Atlantoaxial Joint

Between the articular processes of the two vertebrae.

Intervertebral Disk

Between the vertebrae and articulates with adjacent bodies. 23 beginning between C1 and C3. Main function is to absorb and transmit shock and maintain flexibility of the vertebral column.

What is the action of the scalene muscles?

Bilaterally: assists in neck flexion Unilaterally: neck lateral bending

What is the action of the erector spinae muscle?

Bilaterally: extend neck and trunk Unilaterally: laterally bend neck and trunk

What is the action of the transversospinalis muscle?

Bilaterally: extend neck and trunk Unilaterally: rotate neck and trunk to opposite side

What is the action of the sternocleidomastoid muscle?

Bilaterally: flexes neck, hyperextends head Unilaterally: laterally bends neck; rotates face to the opposite side

What is the action of the external oblique muscle?

Bilaterally: trunk flexion; compression of abdomen Unilaterally: lateral bending; rotation to opposite side

What is the action of the internal oblique muscle?

Bilaterally: trunk flexion; compression of abdomen Unilaterally: lateral bending; rotation to same side

Mastoid Process

Bony prominence behind the ear to which the sternoclidomastoid muscle attaches.

Which joint has no rotation?

C1 (atlas)

Describe the vertebral column:

It establishes and maintains the longitudinal axis of the body. Multijointed rod. Motions of column occur due to combined motions of individual vertebrae. Weight of head, shoulder girdle, upper extremities, and trunk are transmitted through here.

Describe the cervical spine:

It moves freely because weight distribution is not its job. It supports the head and allow freedom of motion of the head on the neck, allows for the nervous tissue to enter the vertebral canal, and allows for entrance and exit of the major blood vessels in the skull.

What are the motions of the atlantoaxial joint?

Lateral bending between C1 & C2; rotation of the head on the neck (shaking head "no").

What does the cervical spine allow?

Movement and positioning of the head.

What is the action of the interspinales muscle?

Neck and trunk extension

What is the action of the intertransversarii muscle?

Neck and trunk lateral bending

Sciatica

Pain that tends to run down the posterior thigh and leg. Caused by pressure on the sciatic nerve roots and usually is symptomatic of an underlying pathology such as a herniated lumbar disc.

Pedicle (Vertebrae)

Portion of the neural arch just posterior to the body and anterior to the lamina.

Lamina (Vertebrae)

Posterior portion of the neural arch that unites from each side in the midline.

Articular Process (Vertebrae)

Projecting superiorly and inferiorly off the posterior surface of each lamina, and so named. Superior articular processes face posteriorly or medially, whereas inferior processes face anteriorly or laterally.

Vertebral curves

Provide the vertebral column with much more strength and resilience.

Posterior Longitudinal Ligament

Runs along the vertebral bodies posteriorly, inside the vertebral foramen. Purpose is to prevent excessive flexion. Thick superiorly, where it helps support the skull. Thin inferiorly, which contributes to instability and increased disk injury in the lumbar region.

Interspinal Ligament

Runs between successive spinous processes.

Anterior Longitudinal Ligament

Runs down the vertebral column on the anterior surface of the bodies and tends to prevent excessive hyperextension. This superiorly and thick inferiorly, where it fuses to the sacrum. Found in the thoracic and lumbar regions just deep to the aorta.

Flexion, extension, and hyperextension occur in the ___ plane around a ___ axis.

Sagittal plane, frontal axis

Lumbar orientation occurs in the ___ plane and contains the motions of ___ & ___.

Sagittal plane; flexion/extension.

Posterior Atlantoaxial Ligament

Serves to secure the weight of the head on the neck.

Thoracic Vertebra:

Size = intermediate; Body shape = heart-shaped, with facets that connect with ribs; Vertebral foramen = smallest; Transverse process = facets that conner with ribs, long, thick and point posteriorly and laterally; Spinous process = long, slender, point inferiorly; Superior articular process = face posteriorly and laterally; Inferior articular process = face anteriorly and medially; Vertebral notches = deeper inferior notches

Lumbar Vertebra:

Size = largest; Body shape = large oval; Vertebral foramen = intermediate; Transverse process = no foramen or articulation; Spinous process = thick, point posteriorly; Superior articular process = face posteriorly; Inferior articular process = face anteriorly; Vertebral notches = deeper inferior notches

Cervical Vertebra:

Size = smallest; Body shape = small oval; Vertebral foramen = large, triangular; Transverse process = foramen for vertebral artery, laterally; Spinous process = short, stout, bifid; Superior articular process = face upward, medially, and posteriorly; Inferior articular process = face laterally; Vertebral notches = equal depth

What are the anterior muscles of the neck?

Sternocleidomastoid, Scalenes (3), and Prevertebral group (4)

Name the muscles of the cervical spine:

Sternocleidomastoid, scalene muscles, splenius capitis, splenius cervicis

Spine, spinal column, vertebral column

Synonymous terms referring to the bony components housing the spinal cord.

Each facet joint is a ___ joint.

Synovial Joint

Anterior Arch

The anterior portion of C1.

Facet Joint

The articulation between superior articular process of vertebra below with the inferior articular process of vertebra above.

Axial Extension (Cervical Retraction)

The combined motion of tucking your chin in that involves the head flexing on C1, as well as the neck (C2-C7) extending.

Atlas (C1)

The first cervical vertebra upon which the cranium rests. Because it supports the globe of the head, it is named after the Titan in Greek mythology who held up the earth. It is ring-shaped and has no body or spinous process.

Spinous Process (Vertebrae)

The most posterior projection on the neural arch; located at the junction of the two laminae. It serves as a point of attachment for many muscles and ligaments and can be palpated though out the length of the vertebral column.

Annulus Fibrosus (Intervertebral Disk)

The outer portion of the disk consisting of several concentrically arranged fibrocartilaginous rings that serve to contain the nucleus pulposus.

Nuchal Line

The ridge running horizontally along the back of the head from the occipital protuberance toward the mastoid processes.

Axis (C2)

The second cervical vertebra is named because it forms the pivot that allows rotation of the atlas (C1), which supports the head.

Occipital Protuberance

The small prominence in the center of the occiput.

Rotation occurs in the ___ plane around a ___ axis, except between the skull and atlas (C1).

Transverse plane, vertical axis

The vertebral column as a whole is considered to be ___.

Triaxial

True or False: Movement in the vertebral column occurs in all three planes.

True

What is the action of the rectus abdominis muscle?

Trunk flexion; compression of abdomen