Anatomy Flashcards
The thoracic skeleton consists of:
- Sternum
- The 12 pairs of ribs and the associated costal cartilages
- The 12 thoracic vertebrae and their associated intervertebral (IV) discs
- Intervertebral (IV) discs are joints located between the vertebrae
The sternum is composed of 3 parts:
Manubrium
Body
Xiphoid process
(The sternal angle is the articulation between the manubrium and the body)
The ______ is the articulation between the manubrium and the body
sternal angle
The sternal angle marks the articulation site for the ____ rib and its ____
The sternal angle marks the articulation site for the 2nd rib and its costal cartilage
The sternal angle is directly opposite the approximate level of the ____ thoracic vertebra
The sternal angle is directly opposite the approximate level of the 4th thoracic vertebra
(or about T4/T5 level)
The ____ is the easily palpable concave notch along the superior border of the manubrium
Jugular notch
The thoracic cage has superior and inferior openings called _____
apertures
The ____ aperture is considered the doorway between the thoracic cavity and the neck
The superior thoracic aperture is considered the doorway between the thoracic cavity and the neck
clinicians generally reger to the superior thoracic aperture as the “thoracic outlet”
The _____ closes the inferior thoracic aperture, separating the thoracic cavity from the ____ cavity
The muscular diaphragm closes the inferior thoracic aperture, separating the thoracic cavity from the abdominal cavity
A typical thoracic vertebra consists of 3 major features:
- Vertebral body- for weight bearing
- Vertebral (neural) arch consisting of pedicles and laminae- protection of the spinal cord
- Numerous (7) processes for muscular attachment and joint surfaces
What portion of the vertebra is used for weight bearing?
The vertebral body
Which portion of the vertebra serves to protect the spinal cord?
The vertebral (neural) arch
(Consists of pedicles and laminae)
What portion of vertebra serves for muscular attachment and joint surfaces?
The numerous (7) processes
______ are heart-shaped and have 2 costal facets- (superior and inferior) on each side of the body for articulation with the head of a rib
Vertebral bodies are heart-shaped and have 2 costal facets- (superior and inferior) on each side of the body for articulation with the head of a rib
_________ are long and slender and have a transverse costal facet for articulation with the tubercle of a rib
Transverse processes are long and slender and have a transverse costal facet for articulation with the tubercle of a rib
Transverse processes are long and slender and have a _________ for articulation with the tubercle of a rib
Transverse processes are long and slender and have a transverse costal facet for articulation with the tubercle of a rib
Spinous processes are long and slant ______
inferiorally
_______ and their associated joint surfaces (facets) serve for articulation with adjacent vertebrae
Articular processes (4) and their associated joint surfaces (facets) serve for articulation with adjacent vertebrae
Articular processes (4) and their associated joint surfaces (facets) serve for articulation with _________
Articular processes (4) and their associated joint surfaces (facets) serve for articulation with adjacent vertebrae
What are the 3 types of ribs?
1.Vertebrocostal (True) - articulates directly with sternum via its own costal cartilage (1-7)
2.Vertebrochondral (False) - indirect articulation with sternum via costal cartilage of the superior rib (8-10)
3.Vertebral (Floating) - do not articulate with sternum, end in the posterior abdominal wall (11-12)
These ribs articulate directly with the sternum via their own costal cartilage:
Vertebrocostal (true) ribs
(1-7)
These ribs articulate indirectly with the sternum via costal cartilage of the superior rib:
Vertebrochondral (False) ribs
(8-10)
These ribs do not articulate with the sternum, and end in the posterior abdominal wall:
Vertebral (floating) ribs
(11-12)
The head of a typical rib has two facets (____ and ____) for articulation with the bodies of two vertebrae. There is a ___ between these two facets.
The head of a typical rib has two facets (superior and inferior) for articulation with the bodies of two vertebrae. There is a crest between these two facets.
The ___ is the slightly constricted area just distal to the head of a typical rib
The neck is the slightly constricted area just distal to the head of a typical rib
The ____ is the portion of the rib located at the junction of the neck and the shaft. It has a ____ for articulation with corresponding transverse process of the vertebra
The tubercle is the portion of the rib located at the junction of the neck and the shaft. It has a facet for articulation with corresponding transverse process of the vertebra
The ____ is the portion of the rib located at the junction of the neck and the shaft. It has a facet for articulation with the corresponding _______ of the vertebra
The tubercle is the portion of the rib located at the junction of the neck and the shaft. It has a facet for articulation with the corresponding transverse process of the vertebra
The ____ has a costal angle where rib turns anterolateral and a costal groove inferiorly for neurovascular structures
The shaft has a costal angle where rib turns anterolateral and a costal groove inferiorly for neurovascular structures
The shaft has a costal angle where rib turns anterolateral and a costal groove inferiorly for ______ structures
neurovascular
The head of typical ribs articulates with two vertebrae:
The body of the numerically corresponding vertebra
and
the body of the vertebra superior to it
e.g. rib 5 articulates with the body of T5 and T4
The tubercle of a typical rib articulates with the ______ transverse process
The tubercle of a typical rib articulates with the numerically corresponding transverse process
e.g. rib 5 articulates with the transverse process of T5
Rib 5 articulates with (3):
Transverse process of T5
Body of T5
Body of T4
Costochondral joint:
cartilaginous joints between the rib and its costal cartilage
Sternocostal joint:
synovial joints between the costal cartilage and the sternum
Costovertebral joints:
synovial joints between the ribs and the vertebral column
the upper limit of the heart reaches as high as the ____ costal cartilage on the right side of the sternum and the ____ intercostal space on the left side of the sternum.
the upper limit of the heart reaches as high as the 3rd costal cartilage on the right side of the sternum and the 2nd intercostal space on the left side of the sternum.
The heart rests on the diaphragm and is covered anteriorly by the _______ and approximately the _____ costal cartilages of both sides.
The heart rests on the diaphragm and is covered anteriorly by the body of the sternum and approximately the 3rd-6th costal cartilages of both sides.
The right margin of the heart extends from approximately the right ____ costal cartilage to near the right ___ costal cartilage.
The right margin of the heart extends from approximately the right 3rd costal cartilage to near the right 6th costal cartilage (at the 6th chondro-sternal junction).
The left margin of the heart descends laterally from the ____ intercostal space to the apex located near the midclavicular line in the ___ intercostal space.
The left margin of the heart descends laterally from the 2nd intercostal space to the apex located near the midclavicular line in the 5th intercostal space.
The lower margin of the heart extends from the sternal end of the right ____ costal cartilage to the apex in the ____ intercostal space near the midclavicular line
The lower margin of the heart extends from the sternal end of the right 6th costal cartilage to the apex in the 5th intercostal space near the midclavicular line
The arch of the aorta lies behind the ______ of the manubrium. The left brachiocephalic vein courses obliquely behind the ____ just above the aortic arch
The arch of the aorta lies behind the sternal angle/lower portion of the manubrium. The left brachiocephalic vein courses obliquely behind the manubrium just above the aortic arch
What is the weakest part of the ribs?
Just anterior to its angle
What ribs are the most commonly fractured?
Middle ribs (5-9) via e.g. auto accidents or sports injuries
Pectus excavatum:
(aka funnel chest) is a condition in which a person’s sternum is sunken into his or her chest
More common in males than females
If the depth of the sternum is severe, it may reduce the ability of the lungs to expand
Severe compression can also squeeze the heart, reducing its ability to fill/pump efficiently
The exact cause is unknown…it may be an inherited (genetic) and/or associated with some syndromes (i.e. Marfan Syndrome
Pectoralis major:
Large fan-shaped muscle in superior thorax
Two heads of origin: clavicular and sternocostal
Inserts into the humerus
Powerful adductor; flexor, and medial (internal) rotator of the arm
Innervated by the medial & lateral pectoral nerves
Pectoralis Minor:
Originates from anterior surface of the 3rd - 5th ribs
Inserts into the coracoid process of the scapula
Stabilizes the scapula against thoracic wall (accessory respiratory muscle also)
Innervated primarily by the medial pectoral nerve
Serratus Anterior Muscle:
Originates on the surface of the 1st - 8th ribs
Inserts into the medial border of the scapula
Stabilizes and protracts the scapula (shoulder blade)
Serratus Anterior…“Boxer’s Muscle”
Innervated by long thoracic nerve
What are the 3 intrinsic muscles of the thorax?
External intercostals
Internal intercostals
Innermost intercostals
The intercostal muscles are all accessory muscles of ____
respiration
What is the order of the neurovascular structures within the costal groove?
VAN:
Intercostal Vein
Intercostal Artery
Intercostal Nerve
Intercostal nerve blocks:
Local anesthetic infiltrated around one or several intercostal nerves to provide anesthesia to thoracic wall
Can be used for reducing pain associated with fractured ribs or to reduce pain associated with bone cancer within the rib cage
How many intercostal muscles are there?
11 on each side (one in each intercostal space)
_____ intercostal muscles course “down and in” and are visualized more laterally
External
_____ intercostal muscles course “down and out” and are visualized more medially
Internal
____ intercostals are located on the inside of the thoracic wall
Innermost intercostals
The neurovascular plane is located between the _____ layer AND the _______ layer. This is where the intercostal nerves, arteries, and veins traverse
The neurovascular plane is located between the internal intercostal muscle layer AND the innermost intercostal layer. This is where the intercostal nerves, arteries, and veins traverse.
The _______ is located between the internal intercostal muscle layer AND the innermost intercostal layer. This is where the intercostal ___, ___, and ____ traverse.
The neurovascular plane is located between the internal intercostal muscle layer AND the innermost intercostal layer. This is where the intercostal nerves, arteries, and veins traverse.
Transversus thoracis muscle:
A particular innermost intercostal
Located on the inside of the thoracic wall, just deep to the sternum
Origin: posterior surface of the sternum
Inserts onto the internal surface of costal cartilages of ribs 2-6