Anatomy and Physiology: Vertebral Column, Thorax and Nervous System

Practice flashcards covering back muscles, spinal anatomy, vertebral curves, thoracic structures, lungs, and the autonomic nervous system as detailed in the lecture transcript.

Axioappendicular Muscles

Muscles of the back that are connected to the shoulder girdle and connect the axial skeleton to the appendicular skeleton.

Superficial Back Muscles

A group of muscles connected to the shoulder girdle, including the Trapezius, Latissimus dorsi, Rhomboids, and Levator scapulae.

Intermediate Back Muscles

Muscles of the back specifically involved with the movement of the thoracic wall.

Deep Back Muscles

Also known as “postvertebral” muscles, these are specifically associated with the vertebral column.

Posterior Rami

The branches arising from the 31 pairs of spinal nerves that supply the skin and segmentally arranged muscles of the back.

Atlas ($C_1$)

The 1st cervical vertebrae which lacks a vertebral body and a spinous process.

Axis ($C_2$)

The 2nd cervical vertebrae characterized by an anterior superior projection known as the dens or odontoid process.

Typical Cervical Vertebrae ($C_3$-$C_7$)

Vertebrae consisting of a body, vertebral (neural) arch, and a foramen transversarium.

Lumbar Vertebrae

The largest vertebrae in the column featuring large, blunt transverse processes.

Sacrum

A single bone consisting of 5 fused sacral vertebrae.

Coccyx

A single bone consisting of 4 fused coccygeal vertebrae.

Cervical Curve

A posterior concave and anterior convex curve extending from the apex of the odontoid process of $C_2$ to $T_2$.

Thoracic Curve

A posterior convex and anterior concave curve extending from $T_2$ to $T_{12}$; classified as a primary structural curve.

Lumbar Curve

A posterior concave and anterior convex curve extending from $T_{12}$ to the sacral promontory, with greatest curvature at the lower 3 vertebrae.

Structural Curves

Also called “primary curves,” these are permanent, fixed curvatures of the spine (like thoracic or sacral) that involve vertebral rotation and do not straighten with positional changes.

Functional Curves

Temporary and flexible curves (like cervical or lumbar) where the spine structure remains normal and the curve disappears when changing positions.

Spinal Canal

The space enclosed by the vertebral body and arch that houses and protects the spinal cord, formed by the alignment of stacked vertebral foramina.

Pedicles

Two short pillars of the vertebral arch that attach the arch directly to the back of the vertebral body.

Laminae

Two flat plates of bone extending from the pedicles to meet in the middle, forming the roof of the vertebral arch.

Articular Processes

Four bony projections (2 superior, 2 inferior) that connect to adjacent vertebrae to form facet joints and guide range of motion.

Intervertebral Disc (IV)

A flexible, fibrous cushion between vertebrae that serves as a symphysis (secondary cartilaginous joint).

Nucleus Pulposus

The gelatinous inner core of the intervertebral disc that absorbs compressive shock.

Annulus Fibrosus

The outer ring of the intervertebral disc that encases the nucleus pulposus and provides structural support.

Zygapophyseal Joints

Also called facet joints, these are paired synovial joints located between the superior and inferior articular processes of vertebrae.

Osteoarthritis

Degenerative arthritis that can cause the breakdown of cartilage between facet joints, leading to pain during movement.

Crepitus

The “popping” sound caused by the cavitation of synovial fluid within facet joints during manual spinal manipulation.

Kyphosis

An abnormal outward curvature of the upper thoracic spine, resulting in a rounded or hunched back (increased posterior convexity).

Lordosis

An abnormal increase in the anterior convexity of the lumbar curve, commonly occurring during pregnancy.

Scoliosis

The most common abnormal curvature, characterized by a lateral deviation or sideways curvature of the spine.

Herniated Disc

A condition where the annulus fibrosus ruptures, causing the nucleus pulposus to protrude posteriorly and potentially press on spinal nerves.

Vertebral Compression Fractures (VCFs)

The most common presentation of spinal fractures where weakened bone collapses under normal pressure.

Spina Bifida Occulta

The mildest and most common form of spina bifida characterized by a small gap in the spine with normal spinal cord and nerves.

Myelomeningocele

The most severe form of spina bifida where the spinal canal remains open, and a sac containing the spinal cord and nerves is exposed.

Ligamenta Flava

Elastic ligaments that connect the laminae of adjacent vertebrae along the posterior boundary of the vertebral canal.

Intervertebral Foramina

Lateral openings formed by gaps between adjacent pedicles that serve as passageways for spinal nerves and blood vessels.

Foramen Magnum

The large oval opening in the occipital bone of the skull where the brainstem connects to the spinal cord.

Conus Medullaris

The tapered, wedge-shaped lower end of the spinal cord located around the $L_2$ vertebra.

Spinal Dura Mater

The thick, tough, fibrous outermost layer of the meninges that protects the spinal cord.

Subarachnoid Space

The space between the arachnoid and pia mater that is filled with cerebrospinal fluid (CSF) and houses spinal blood vessels.

Filum Terminale

A strand of fibrous tissue extending from the conus medullaris to the $Co_2$ vertebra, anchoring the spinal cord.

Denticulate Ligaments

Paired triangular bands of spinal pia mater that anchor the cord laterally to the dura mater.

Epidural Space

The outermost compartment of the spinal canal located between the vertebrae and the dura mater, containing adipose tissue and the internal venous plexus.

Lumbar Cistern

An enlarged subarachnoid space found between $L_2$ and $S_2$ that contains the cauda equina and is the site for lumbar punctures.

Cauda Equina

Bundles of nerve roots at the lower end of the spinal cord consisting of lower lumbar and sacral spinal nerves.

Dorsal Root

The posterior connection of a spinal nerve to the cord containing only sensory (afferent) fibers.

Ventral Root

The anterior connection of a spinal nerve to the cord containing only motor (efferent) fibers.

Dermatome

A specific area of skin that sends sensory information to a single spinal nerve root.

Myotome

A group of muscles innervated by a single spinal nerve level for motor action.

Costal Margin

The lower boundary of the thorax formed by the cartilage of ribs 7 through 10.

True Ribs

Rib pairs 1 through 7 which attach directly to the sternum via individual costocartilages.

Floating Ribs

Rib pairs 11 and 12 which have no anterior connection.

VAN Structure

The arrangement of the intercostal Vein, Artery, and Nerve located in the costal groove at the top of the intercostal space.

Pectoralis Major

A thoracic muscle innervated by both the medial and lateral pectoral nerves.

Serratus Anterior

A muscle responsible for holding the scapula against the ribcage, innervated by the long thoracic nerve; damage causes "winging" of the scapula.

Retromammary Space

The space between the breast tissue and the deep fascia covering the pectoral muscles.

Peau d'orange

A pitted, dimpled skin texture on the breast caused by blocked lymphatic vessels, often indicating breast cancer.

Axillary Sheath

Deep fascia that encompasses the brachial plexus and axillary vessels; it helps localize anesthetics during nerve blocks.

Brachial Plexus

A nerve bundle originating from $C_5$-$T_1$ that provides nerves to the upper limbs and parts of the thorax.

Thoracic Outlet Syndrome

Compression or irritation of nerves or blood vessels in the superior thoracic aperture between the neck and armpit.

Ventral Horns

Regions of gray matter in the spinal cord that house somatic motor nuclei.

Lateral Horns

Regions of gray matter in the spinal cord (specifically $T_1$-$L_2$) that house visceral motor nuclei for the sympathetic nervous system.

Sympathetic Nervous System

The "Fight or Flight" division of the ANS with nerves originating in the thoraco-lumbar regions ($T_1$-$L_2$).

Parasympathetic Nervous System

The "Rest and Digest" division of the ANS with nerves originating from cranial nerves ($III$, $VII$, $IX$, $X$) and sacral levels ($S_2$-$S_4$).

Referred Pain

Sensation felt in one part of the body derived from an injury in an organ, presenting in dermatomes supplied by the organ's sympathetic innervation.

Mediastinum

A thick median partition between the pleural cavities extending from the sternum to the backbone, housing all major thoracic organs except the lungs.

Ligamentum Arteriosum

A fibrous remnant of the fetal ductus arteriosus that connects the left pulmonary artery to the aortic arch.

Thoracic Duct

The largest lymphatic vessel in the body, providing drainage for all of the body except the right side of the head, neck, thorax, and right upper limb.

Costodiaphragmatic Recess

The largest potential space in the pleural cavity located where the chest wall meets the diaphragm, allowing for lung expansion.

Lingula

A tongue-shaped flap of tissue on the bottom-most section of the left lung's upper lobe, located below the cardiac notch.

Horizontal Fissure

A lung fissure seen only on the right lung, separating the upper lobe from the middle lobe.

Hilum

A wedge-shaped depression on the medial surface of the lung where the root of the lung (bronchus, vessels, nerves) enters and exits.

Conducting Zone

The respiratory passageways (trachea, bronchi) that filter and warm air but do not participate in gas exchange.

Respiratory Zone

Deep microscopic lung tissues, such as alveoli, where gas exchange actually occurs.

Pericardium

A fibroserous sac that encloses the heart and the roots of the great vessels, composed of fibrous and serous layers.

Coronary Sinus

The largest vein in the heart, located on the posterior surface, which delivers deoxygenated blood directly into the right atrium.

Azygos Vein

An unpaired vein running on the right side of the body that drains the thoracic wall and terminates in the superior vena cava.