Chapter 2, THE SUPPORT STRUCTURE OF RESPIRATION

structures of respiration

1. bony thorax 2. visceral thorax 3. muscles of respiration

rib cage has 12 ribs divided into

7 true ribs, 3 false ribs, 2 floating ribs

chondral

Cartilaginous; often refers to the portion of the ribs that connect the rib bones to the sternum

final respiratory exchange region as a series of apartment houses

The respiratory bronchioles are the entryways for each apartment building, and the alveolar duct is the passageway to the individual "apartment", the alveolus.

trachea

a flexible tube, composed of a series of 16-20 hyaline cartilage rings that are open in the posterior aspect. This tube runs from the inferior border of the larynx for about 11cm where it bifurcates (divides) at a point known as the carina trachea to become left & right main stem brochi (or bronchial tubes), which serve the left and right lungs respectively. The trachea must be both rigid and flexible. It is built of hyaline cartilage rings connected by fibroelastic membrane. The cartilage provides support, while the membrane permits freedom of movement

ilium

a large, wing-like bone that provides the bulk of support for the abdominal musculature and the prominent hip bone

esophagus

a long, collapsed tube running parallel to and behind the trachea, providing a conduit to the digestive system

clavicle

aka collarbone, attached to the superior sternum, running laterally to join with the wing-like scapula. The clavicle provides the anterior support for the shoulder. Has its only skeletal attachment at the sternum/breast plate.

scapula

aka shoulder blade, the major structure of the pectoral girdle. Has its only skeletal attachment via the clavicle/collarbone. From the scapula are slung several muscles that hold it in a dynamic tension that facilitates flexible upper body movement without compromising strength

corpus

body

vertebral foramen

canal through which spinal cord passes. foramen of vertebral segment through which spinal cord passes

ribs

capable of a degree of movement so that the rib cage can rock up in front and flare out via lateral rotation, being hinged on the vertebral articulation with the rib cage. The rib cage is made up of 12 ribs, with all but the lowest 2 attached by means of cartilage to the sternum in the front aspect. The rib cage tends to slant down in front. The mobility of the rib cage is quite capable of elevating during inspiration to increase the size of the thorax. The rib cage gives significant protection to the heart & lungs.

5 divisions of the vertebral column

cervical, thoracic, lumbar, sacral, and coccygeal

tracheal rings

connected by a continuous mucous membrane lining which provides both continuity and flexibility. The gap between the rings is spanned by smooth muscle that is in a steady state of contraction until oxygen needs of an individual increase, at which time the muscle relaxes. The tube is in a state of slight constriction until oxygen needs are sufficiently great that the muscle action is inhibited, at which time the diameter of the trachea increases to improve air delivery to the lungs.

True, aka vertebrosternal ribs

consists of the upper ribs (1-7), all of which form more or less direct attachment with the sternum. Their actual attachment is by means of a cartilaginous union through the chondral portion of the rib

Right main stem bronchus

divides to supply the superior, middle, and inferior lobes of the right lung

Left main stem bronchus

divides/bifurcates to serve the superior and inferior lobes of the left lung, although there is a vestigial middle lobe (the lingula)

coccyx

four vertebrae fused together to form the tailbone. the fused coccygeal vertebrae, named after cuckoo because it is shaped like a birds' beak.

Manubrium sterni

handle of the sternum. provides the attachment of the clavicle and the first rib

4 components of ribs

head, neck, shaft, and angle

pelvic girdle

how the lower extremities are attached to the vertebral column- an area comprised of the ilium, sacrum, pubic bone, and ischium. The combination provides an extremely strong structure capable of bearing a great deal of translated weight from the use of the legs.

pectoral girdle

how the upper extremities are attached to the vertebral column

Type 1 (membranous) pneumocytes

in the alveoli, flat cells that are directly involved in gas exchange

Shoulder girdle, aka pectoral girdle

includes the scapula and clavicle, bones that support the upper extremities

bronchial tree

inside the lungs; characterized by increasingly smaller tubes as one progresses into the depths of the lungs. The left and right stem bronchi bifurcate (divide) off the trachea to serve the left and right lungs, respectively. The third level of branching serves the segments of each lobe. At this third level of division, the bronchi divide repeatedly into smaller and smaller cartilaginous tubes, with the final tube being the terminal bronchiole. This repeated branching has an important effect on respiratory function, amazing amount of surface area for respiration. The first 9 divisions of the bronchial tree are strictly conductive and cartilaginous, being designed only to transport gas between the environment and the lungs. The final 7 divisions are actual respiratory zones comprised of the respiratory bronchioles, alveolar ducts, and alveoli.

lungs

made of blood, arterial and venous network, connective tissue, the respiratory pathway, and tissue specialized for gas exchange

intervertebral foramen

opening located between adjacent vertebrae for exit of a spinal nerve. foramen through which spinal nerve exits and/or enters the spinal cord, located on either side of the vertebra

foramina

openings in bones that allow nerves and blood vessels to enter or leave the bone

spinous process

posterior most process of vertebrae- what you can feel when you rub someone's spine

Corpus (of the sternum)

provides articulation for 5 more ribs by means of relatively direct costal cartilage

Floating, aka vertebral ribs

ribs 11 & 12, articulate only with the vertebral column

False, aka vertebrochondral ribs

ribs 8-10 that are attached to the sternum by means of cartilage, although this chondral portion must run superiorly to attach at the sternum

lobar

secondary, intermediate- bronchial passageways connecting the mainstem bronchi with individual lobes of the lungs, supply the lobes of the lungs.

transverse process

specific part of the atlas (C1). lateral process of vertebrae

sacrum

the 5 sacral vertebrae fused as mass

axis

the C2 vertebra on which the skull pivots

pulmonary artery

the artery that branches to follow the bronchial tree, ultimately serving the gas exchange process to the alveolar level.

vertebral column

the bony structure made of vertebrae. The entire thorax is suspended from it. Composed of 33 segments of bone with a rich set of fossa and protuberances clearly designed for function. Although vertebrae have roughly the same shape, their form and landmarks vary depending on the location and the area they serve, their attachments, and their neural payload.

sternum

the breastbone, provides a vocal point for the rib cage, and the sternum turns out to be a significant structure for respiration

aspiration

the entry of liquid or solid materials into the lungs. Fluids or solids may enter the lungs as a result of some failure in strength, coordination, sensation, or awareness. Signs of aspiration are if the client's voice sounds wet or gurgly, or if the client has a history of respiratory illnesses.

vertebra/vertebrae

the functional unit of the vertebral column. Vertebrae are numbered sequentially from superior to inferior (top to bottom) by section: cervical vertebrae at the top, then thoracic vertebrae, then lumbar vertebrae, then the sacrum, then the coccyx. Vertebrae are seperated by intervertebral discs, which are made of fibrocartilage. Each disc consists of a gelatinous core that equalizes forces placed on the disc (the nucleus pulposus) and a fibrous ring knows as the annulus fibrosus. The role of the disc is to keep the vertebrae separated, and to allow free space for passage of the spinal nerves from the spinal cord to the periphery.

pubic symphysis

the joint and point of union between the 2 pubic bones in the pelvic girdle

Terminal respiratory bronchioles

the last bronchioles in the respiratory tree, connecting the respiratory tree to the alveoli. Small, and at its end becomes the alveolar duct, which in turn communicates with the alveolus.

shaft of rib

the long, relatively straight component of a rib, between the neck and the angle of the rib

3 components of the sternum

the manubrium sterni, the corpus (body), and the xiphoid or ensiform process

spinal cord

the nervous system supply for the body and extremities

Manubrosternal angle

the point of articulation of manubrium sterni and corpus, the 2nd rib articulates at this juncture

angle of rib

the portion of the rib between the head and shaft, at which the direction of the rib takes an acute turn

Type 2 (cuboidal) pneumocytes

the source of the surfactant, a substance that reduces surface tension, which is released into the alveolus to alter the surface tension to keep the alveoli from collapsing during respiration. When Type 1 cells are damaged, Type 2 cells will proliferate, becoming Type 1 cells in a regenerative process.

Suprasternal aka sternal notch

the superior surface of the manubrium sterni

atlas

the uppermost cervical vertebra, C1, supporting the skull for rotation- named after the mythical atlas figure that supports the world

palpation

to examine by touch. the process of examining structures with the hands, very useful when understanding anatomy. SLPs use palpation when you perform an oral peripheral examination as a clinician, it is a means of gathering information about your client's physical condition that may help your diagnosis and the remediation of speech problems

3 classes of ribs

true ribs, false ribs, and floating ribs

cervical vertebra(e)

vertebra of the cervical spinal column, numbered from C1 at the top, down to C7.

lumbar vertebra(e)

vertebra of the lumbar spinal column, numbered L1 at the top down to L5. These are quite large in comparison because of the stress placed on them during lifting and ambulation/walking. They provide direct or indirect attachment for a host of back and abdominal muscles, as well as for the posterior fibers of the diaphragm.

thoracic vertebra(e)

vertebra of the thoracic spinal column, numbered T1 at the top, down to T12. The 12 thoracic vertebrae (T1 to T12) provide the basis for the respiratory framework, because they form the posterior point of attachment for the ribs of the bony thorax. You should pay particular attention to the superior and inferior costal facets, because these are the points of attachment for the ribs. The first rib and the last 3 ribs (1, 10, 11, 12) attach nicely one-to-one. Each of the remaining ribs (2-9) attaches to the transfers process and corpus of the same-numbered vertebra and also attaches to the body of the vertebra above it (eg rib 2 attaches to transverse process of T2 and body of T1 and T2)

sacral vertebra(e)

vertebral components of the sacrum, numbered S1 down to S5.

coccygeal vertebrae

vestigial vertebral components of the coccyx, they are considered to be a fused unit, known as the coccyx.