Components of the thoracic cage

Professor Odom

Levels of Organization

Learning Objectives

Describe and Understand the Axial and Appendicular Skeleton

Identify the bones and bony structures of the skull, the cranial suture lines, the cranial fossae, and the openings in the skull

Discuss the vertebral column and regional variations in its bony components and curvatures

Be able to compare and contrast each segment of vertebrae

Describe the components of the thoracic cage

Identify key features for each axial and appendicular bones

Identify the features of the pelvis and explain how these differ between the adult male and female pelvis

Axial Skeleton: Overview

80 bones in the axial skeleton

Cephalic

Cranial (8)

Facial (14)

Auditory Ossicles (6)

Hyoid (1)

Thoracic Cage

Ribs (24)

True Ribs (14 total)

False Ribs (6 total)

Floating (4 total)

Sternum (1)

Vertebral Column

Vertebrae

Cervical (7)

Thoracic (12)

Lumbar (5)

Sacrum (1)

Coccyx (1)

This is more for overview, they don’t need to know the specific numbers for everything, EXCEPT true false and floating ribs

True-1-7

False-8-10

Float-11,12

Real-Quick-Review True or False

1. Bone growth occurs between the diaphysis and the epiphysis in the epiphyseal line

2. When growth is complete, the epiphyseal plate becomes the epiphyseal line

3. Hyaline cartilage is the least abundant throughout the body

4. The ribs would be classified as axial skeleton

False, plate

True

False, most abundant

True

Axial Skeleton: Cephalic: Cranial

Frontal

Sphenoid

Ethmoid

Temporal

Parietal

Occipital

Know and be able to identify each of these bones

KNOW THESE REALLY WELL 

Axial Skeleton: Cephalic: Facial

Palantine

Know and be able to identify each of these bones

KNOW THESE REALLY WELL 

The bones of the skull are the only things from these two slides that they’ll need to know for their quiz, but they WILL need to know foramina and other bone markings for their practical. A study guide will be posted next weekend with details regarding which bones/bone markings they need to know for the practical.

Foramen of Skull

Foramen of Sphenoid Bone

Axial Skeleton: Hyoid

Floats at the level of cervical vertebrae 3

Does not articulate other bones

Attached by ligaments from styloid and hangs like a swing

Serves as attachment site for other muscles

Cornu=horn

It exists

There’s not a whole lot they need to know about the hyoid—really just the three things in red. 

Axial Skeleton: Vertebral Column Anatomical Shape

Concave

Convex

Axial Skeleton: Vertebral Column Pathologic Shape

Scoliosis: Abnormal lateral curvature

Kyphosis: exaggerated thoracic curvature

Lordosis: exaggerated lumbar curvature

Mention pathologies associated with spinal column—kyphosis, lordosis, scoliosis

Anatomy of Individual Vertebrae

Vertebral Body

Vertebral Arch

Pedicle – (pillars)

Lamina – (arch)

Vertebral Foramen (opening/hole)

Spinous process (Process = projection)

Transverse processes

Anatomy of Individual Vertebrae

Vertebral Body

Vertebral Arch

Pedicle – (pillars)

Lamina – (arch)

Vertebral Foramen (opening/hole)

Spinous process (Process = projection)

Transverse processes

Axial Skeleton: Vertebrae:

C1-C7 vertebrae

C1=atlas

C2=axis

Dens

C7=vertebral prominens

Identifying Characteristics

Large vertebral foramina

Transverse Foramen

Bifid spinous process

Vertical angle

Small body

Transverse Foramen

Bifid Spinous Process

Cervical

Elephant 

They need to know C1 and C2 as well as their common names, Atlas and Axis

They need to know it is C7 they can easily palpate on themselves and others

Spend some time on the different types of vertebra, they’ll need to know how to identify each kind

Axial Skeleton: Vertebrae:

T1-T12

Identifying Characteristics

Medium size body

Costal facets that articulate with ribs

Vertically angled spinous process

Thoracic

Giraffe 

Axial Skeleton: Vertebrae:

L1-L5

Identifying Characteristics

Large bodies

Small vertebral foramina

More horizontal spinous process

Triangular vertebral foramen

Lumbar

Giraffe 

Difference between Vertebrae

Axial Skeleton: Vertebrae:

Sacrum is 5 fused vertebrae

S1 – S5

Base of Sacrum

Median Sacral Crest

Superior Articular Facet

Sacrum

Giraffe 

Axial Skeleton: Vertebrae:

Coccyx aka “tailbone”

Consists of 3-5 fused vertebrae

Anchors spinal cord

Coccyx

Giraffe 

Intervertebral Discs

intervertebral disc is a fibrocartilaginous pad that fills the gap between adjacent vertebral bodies

anulus fibrosus is the tough, fibrous outer layer of the disc. It forms a circle (anulus = “ring” or “circle”) and is firmly anchored to the outer margins of the adjacent vertebral bodies. Inside is the

nucleus pulposus, consisting of a softer, more gel-like material. It has a high water content that serves to resist compression and thus is important for weight bearing.

Herniated Disc

Herniation can happen when the Nucleus pulposus buldges through the annular layer

This can cause a pinched nerve

Important Ligaments of Vertebral Column

Supraspinous ligament is located on the posterior side of the vertebral column, where it interconnects the spinous processes of the thoracic and lumbar vertebrae. This strong ligament supports the vertebral column during forward bending motions. In the posterior neck, where the cervical spinous processes are short, the supraspinous ligament expands to become the nuchal ligament (nuchae = “nape” or “back of the neck”). The nuchal ligament is attached to the cervical spinous processes and extends upward and posteriorly to attach to the midline base of the skull, out to the external occipital protuberance. It supports the skull and prevents it from falling forward.

Important Ligaments of Vertebral Column

Anterior longitudinal ligament – lies anterior to vertebral body. It serves to resist excess backward bending of the vertebral column.

Posterior longitudinal ligament – lies posterior to the vertebral body and anterior to the spinal cord.

Ligamentum flavum (“yellow ligament”). This consists of a series of short, paired ligaments, each of which interconnects the lamina regions of adjacent vertebrae. It lies posterior to the spinal cord.

Real-Quick-Review Fill-In-The-Blank

1. C1 and C2 are also called the ________ and the __________

2. From the side, a ________ vertebra looks like a giraffe

3. From the side, a _________ vertebra looks like a moose

4. From the side, a _________ vertebra looks like an elephant

Atlas, Axis

Thoracic

Lumbar

Cervical

Axial Skelton: Thoracic Cage Anatomy of Sternum

Thoracic cage protects vital thoracic organs

Sternum is three fused bones

Manubrium, Body, and Xiphoid

Axial Skelton: Thoracic Cage Anatomy of Rib

Head- lies posterior and articulates with the sup/inf costal facets of thoracic vertebrae

Neck- lies between the head and tubercle

Articular facet of tubercle articulates with costal facet of transverse process

Costal groove- runs inferiorly and protects blood vessels and nerves

Angle of the rib- is the greatest curvature of the rib, just after the tubercle

Axial Skelton: Thoracic Cage

Ribs attach to the sternum via the costal cartilages

True Ribs 1-7

False Ribs 8-12

False Floating ribs are 11,12

Counting Ribs

{

True

Ribs

7 True Ribs on R side, so how many total?

}

False

Ribs

Floating Ribs

5 False Ribs on L side, so how many total?

How many of those are “floating”?

Axial Skeleton Review

Consists of:

Skull

Frontal

Sphenoid

Ethmoid

Parietal

Occipital

Temporal

Nasal

Lacrimal

Zygomatic

Maxilla

Mandible

Palatine

Vertebral Column

Cervical

Thoracic

Lumbar

Sacral

Coccyx

Laryngeal Skeleton, Hyoid

Thoracic Cage

Sternum

Manubrium

Body of Sternum

Xiphoid Process

Ribs

True

False

Floating

Appendicular Skeleton: Overview

Appendicular Skeleton (126)

Pectoral Girdle

Clavicles (2)

Scapula (2)

Upper Limbs

Humerus (2)

Radius (2)

Ulna (2)

Carpals (16)

Metacarpals (10)

Phalanges (28)

Pelvic Girdle

Os coxae (2)

Lower Limbs

Femur (2)

Patella (2)

Tibia (2)

Fibula (2)

Tarsals (14)

Metatarsals (10)

Phalanges (28)

Just an overview

Pectoral Girdle

Consists of:

Clavicle

Scapula

Pectoral Girdle: Clavicle

Orientation: The flat sternal end points medially, the acromial curve points anteriorly, and the conoid tubercle points inferiorly.

AC Joint: Acromion process and articulation of the clavicle

Help them learn to orient, since they’ll need to be able to differentiate right from left on the practical. They’re usually pretty nervous about this at first, but if you just calm them down and show them what to look for, they’ll see that it IS possible and it won’t seem quite so intimidating. 😉

Pectoral Girdle: Scapula

Orientation: The glenoid cavity faces laterally and the spine projects posteriorly. Coracoid process is more anterior than the acromial process.

Upper Limb: Arm: Humerus

Orientation: Head is directed medially while deltoid tuberosity is angled laterally. Olecranon fossa is located posteriorly.

Upper Limb: Forearm: Radius & Ulna

Orientation: The ulna is medial while the radius is lateral. The radial tuberosity is directed medially and rough surface on distal end is posterior. The ulnar styloid process is medial while the radial styloid is lateral. Trochlear notch faces anteriorly.

Radius rotates over the ulna

Upper Limb: Hand: Overview

Components of the Hand (from proximal to distal) :

Carpals (wrist)

Metacarpals (palm)

Phalanges (fingers)

Radius leads to the thumb while the ulna leads to the pinky.

Upper Limb: Hand: Carpals

Carpals – Greek Word for Wrist (think carpentry):

Scaphoid

Lunate

Triquetrum

Pisiform

Hamate

Capitate

Trapezoid

Trapezium

Long

Pinky,

Here

Comes

The

Thumb

Upper Limb: Hand: Carpals

Long

Pinky,

Here

Comes

The

Thumb

Carpals – Greek Word for Wrist (think carpentry):

Scaphoid

Lunate

Triquetrum

Pisiform

Hamate

Capitate

Trapezoid

Trapezium

Upper Limb: Hand: Metacarpals

Numbered (1-5) beginning laterally:

Phalange

Upper Limb: Hand: Phalanges

Numbered (1-5) beginning laterally:

Phalange

Each phalange has:

Proximal

Middle

Distal

**Only exception is 1st phalange, has proximal & distal (no middle)

Name the bone:

Answers:

Scaphoid

1st Metecarpal

5th Metecarpal

3rd middle phalynx (phalange)

1st proximal phalynx (phalange)

Capitate

Appendicular Skeleton: Overview

Appendicular Skeleton (126)

Pectoral Girdle

Clavicles (2)

Scapula (2)

Upper Limbs

Humerus (2)

Radius (2)

Ulna (2)

Carpals (16)

Metacarpals (10)

Phalanges (28)

Pelvic Girdle

Os coxae (2)

Lower Limbs

Femur (2)

Patella (2)

Tibia (2)

Fibula (2)

Tarsals (14)

Metatarsals (10)

Phalanges (28)

Just an overview

Pelvic Girdle: Os Coxae

The Os coxae is formed by the fusion of three bones:

Ilium

Ischium

Pubis

Orientation: Acetabulum is directed laterally, ischial spine points posteriorly, and connection of pubic bones at pubic symphysis is located anteriorly.

Pelvic Girdle: Os Coxae

The Os coxae is formed by the fusion of three bones:

Ilium

Ischium

Pubis

Orientation: Acetabulum is directed laterally, ischial spine points posteriorly, and connection of pubic bones at pubic symphysis is located anteriorly.

Important Ligaments of Pelvic Girdle

The pelvic girdle is held tightly to the axial skeleton via four major ligament:

Anterior sacrospinous ligament

Posterior sacrospinous ligament

Sacrospinous ligament

Sacrotuberous ligament

**This is different from the Pectoral girdle, which is highly mobile and attached via muscle

Important Foramen of Os Coxae

Greater sciatic foramen is formed by the greater sciatic notch, the sacrum, and the sacrospinous ligament.

Lesser sciatic foramen is formed by the lesser sciatic notch, the sacrospinous and the sacrotuberous ligaments.

Obturator Foramen is formed by the articulation of the pubic bone and the ischium.

Greater and Lesser Pelvis

Greater Pelvis / False Pelvis lies superior to the pelvic inlet

Large and small Intestines, sigmoid colon

Divided by Pelvic Inlet/Outlet & Pelvic Brim

The Pelvic Brim is the boarders of the pelvic inlet and outlet

The Pelvic Inlet is the area within the pelvic brim looking from a superior view

Lesser Pelvis / True Pelvis lies between the pelvic inlet and outlet

Urinary bladder, reproductive organs, rectum

Greater and Lesser Pelvis

Greater Pelvis / False Pelvis lies superior to the pelvic inlet

Large and small Intestines, sigmoid colon

Divided by Pelvic Inlet/Outlet & Pelvic Brim

The Pelvic Brim is the boarders of the pelvic inlet and outlet

The Pelvic Inlet is the area within the pelvic brim looking from a superior view

The Pelvic Outlet is the area within the pelvic brim looking from a inferior view

Lesser Pelvis / True Pelvis lies between the pelvic inlet and outlet

Urinary bladder, reproductive organs, rectum

Greater and Lesser Pelvis

Greater Pelvis / False Pelvis lies superior to the pelvic inlet

Large and small Intestines, sigmoid colon

Divided by Pelvic Inlet/Outlet & Pelvic Brim

The Pelvic Brim is the boarders of the pelvic inlet and outlet

The Pelvic Inlet is the area within the pelvic brim looking from a superior view

The Pelvic Outlet is the area within the pelvic brim looking from a inferior view

Lesser Pelvis / True Pelvis lies between the pelvic inlet and outlet

Urinary bladder, reproductive organs, rectum

Differences Male vs Female Pelvis

	Female pelvis	Male pelvis
Pelvic weight	Bones of the pelvis are lighter and thinner	Bones of the pelvis are thicker and heavier
Pelvic inlet shape	Pelvic inlet has a round or oval shape	Pelvic inlet is heart-shaped
Lesser pelvic cavity shape	Lesser pelvic cavity is shorter and wider	Lesser pelvic cavity is longer and narrower
Subpubic angle	Subpubic angle is greater than 80 degrees	Subpubic angle is less than 70 degrees
Pelvic outlet shape	Pelvic outlet is rounded and larger	Pelvic outlet is smaller
False Pelvis Depth	False pelvis is more shallow	False pelvis is deeper

Lower Limb: Thigh: Femur

Orientation: Head is directed medially while greater trochanter is directed laterally. The intercondylar fossa is located posteriorly while patellar surface is anterior.

Lower Limb: Knee: Patella

Orientation: The apex is the inferior most feature. Posterior medial facet is smaller than lateral facet.

Lower Limb: Leg: Tibia & Fibula

Orientation: Fibula is lateral while the tibia is medial

Fibular malleolus is lateral while Tibial malleolus is medial. Tibial tuberosity is anterior.

Lower Limb: Foot:

The Foot has three components (from proximal to distal):

Tarsals

Metatarsals

Phalanges

Lower Limb: Foot: Tarsals

Tarsals

Talus

Calcaneus

Navicular

Medial Cuneiform

Intermediate Cuneiform

Lateral Cuneiform

Cuboid

Tiger

Cubs

Need

MILC

Help them learn to orient. Mnemonic start on the top of the foot with the talus, below it to the calcaneus, and then moves clockwise towards the big toe and around to the little toe.

Lower Limb: Foot: Metatarsals

Numbered (1-5) beginning medially:

Phalange

Lower Limb: Foot: Phalanges

Numbered (1-5) beginning medially:

Phalange

Each phalange has:

Proximal

Middle

Distal

**Only exception is 1st phalange, has proximal & distal (no middle)

Name the Bone

Navicular

Talus

Calcaneus

Lateral cuneiform

1st Proximal Phalynx (Phalange)

5th Distal Phalynx (Phaleange)

Congratulations you’ve now learned the entire Axial and Appendicular Skeleton!

Calculate Price

Price (USD)

ORDER NOW

Pro Academia Help

Components of the thoracic cage

Calculate Price

Don't Miss Our Special Offers