Back and Vertebral Column Lecture Review

Comprehensive vocabulary flashcards covering the anatomy, joints, clinical conditions, and innervation of the back and vertebral column based on the lecture transcript.

Primary Curvatures

Curvatures that are concave anteriorly, specifically the thoracic and sacral curvatures.

Secondary Curvatures

Curvatures that are convex anteriorly, specifically the cervical and lumbar curvatures.

Vertebra total count

There are $33$ total vertebrae in the human body: $7$ cervical, $12$ thoracic, $5$ lumbar, $5$ sacral, and $3-4$ coccygeal.

Adult Vertebra Count

There are $26$ vertebrae in a mature adult.

Typical Vertebra Processes

Each typical vertebra has seven processes: one spinous process, two transverse processes, and four articular processes (two superior and two inferior).

Atlas (C1)

The first cervical vertebra, which is unique because it has neither a body nor a spinous process, but has paired lateral masses to bear the weight of the cranium.

Axis (C2)

The strongest cervical vertebra, distinguished by the tooth-like dens (odontoid process) projecting superiorly from its body.

Dens (Odontoid Process)

A blunt tooth-like projection that projects superiorly from the body of the axis ($C2$).

Prevalence of Atlantoaxial Instability (AAI)

Occurs in $6.8\%$ to $27\%$ of the Down Syndrome population and approximately $0.03\%$ in the general population.

Kyphosis

An abnormal clinical curvature of the spine.

Hyperlordosis

An abnormal clinical curvature of the spine, often seen in the lumbar region.

Scoliosis

An abnormal lateral clinical curvature of the spine.

Zygapophyseal Joints

Also known as facet joints, these are synovial joints formed by the superior and inferior articulating processes of adjacent vertebrae.

Intervertebral (IV) Joints

Cartilaginous joints between adjacent vertebral bodies designed for weight bearing and strength.

Nucleus Pulposus

The inner part of the intervertebral disc; herniations of this substance usually extend posterolaterally.

Annulus Fibrosus

The outer portion of the intervertebral disc that is relatively thin and houses the nucleus pulposus.

Most common disc herniation level

The $L4/L5$ level, followed by the $C5/C6$ level.

Laminectomy

The surgical removal of a portion of the lamina to access a damaged disc.

Conus Medullaris

The lower end of the spinal cord, located opposite the $L1/L2$ vertebrae.

Cauda Equina

The collection of spinal nerve roots located below the conus medullaris.

Spinal Cord Segments

There are $31$ segments: $8$ cervical, $12$ thoracic, $5$ lumbar, $5$ sacral, and $1$ coccygeal.

Lumbar Puncture (Spinal Tap)

A procedure typically performed between the $L4$ and $L5$ vertebrae.

Posterior (Dorsal) Roots

Roots of the spinal nerve that carry sensory information.

Anterior (Ventral) Roots

Roots of the spinal nerve that carry motor information.

Dermatome

The area of skin innervated by a given spinal cord segment via its spinal nerve.

Myotome

The collection of striated muscle fibers innervated by a given spinal cord segment via its spinal nerve.

C8 Spinal Nerve

The spinal nerve that exits caudal to the $C7$ vertebra (between $C7$ and $T1$).

Extrinsic Back Muscles

Muscles like the trapezius and latissimus dorsi (superficial) or serratus posterior (intermediate) that move limbs or assist in respiration.

Erector Spinae Group

Deep intrinsic back muscles innervated by dorsal rami that extend the spine bilaterally and flex it laterally unilaterally.