Skeletal System Part B. VERTEBRAL COLUMN Extends from the skull to the pelvis and protects the spinal cord. Extends from the skull to the pelvis and

Skeletal Skeletal System Part BSystem Part B

Skeletal Skeletal System Part BSystem Part B

VERTEBRAL VERTEBRAL COLUMNCOLUMN

Extends from the skull to the pelvis Extends from the skull to the pelvis and protects the spinal cord. and protects the spinal cord.

It is composed of a vertebrae It is composed of a vertebrae separated by intervertebral disk.separated by intervertebral disk.

An infant has 33 vertebral bones and An infant has 33 vertebral bones and an adult has 26an adult has 26

The vertebral bones have 4 The vertebral bones have 4 curvatures- Cervical, thoracic, lumbar, curvatures- Cervical, thoracic, lumbar, and pelvic.and pelvic.



VertebraVertebra

A Typical VertebraA Typical Vertebra All vertebrae have a All vertebrae have a

common structural common structural pattern. Each pattern. Each vertebra consists of a vertebra consists of a body, vertebral arch, body, vertebral arch, vertebral foramen vertebral foramen and vertebral canal.and vertebral canal.

VertebraVertebra

Cervical Vertebrae (7)Cervical Vertebrae (7) C1 and C2 are the smallest and are C1 and C2 are the smallest and are

unusual. Often called the atlas and the unusual. Often called the atlas and the axisaxis

They have no intervertebral disc They have no intervertebral disc between them and are highly modified. between them and are highly modified.

The dens of the axis (2The dens of the axis (2ndnd vertebra) vertebra) provides a pivot for the atlas when the provides a pivot for the atlas when the head is turned from side to side.head is turned from side to side.

C1 has no spinous process nor body.C1 has no spinous process nor body.

VertebraVertebra

Cervical Vertebrae Cervical Vertebrae (7)(7)

The remaining The remaining cervical vertebra help cervical vertebra help to make up the neck. to make up the neck.

Thoracic Thoracic Vertebrae (12)Vertebrae (12)

Larger than the Larger than the cervicalcervical

Slope downward Slope downward and faces the sides and faces the sides of bodies articulate of bodies articulate with the ribswith the ribs

VertebraVertebra

Lumbar Lumbar Vertebrae (5)Vertebrae (5)

Large and strongLarge and strong

VertebraVertebra

Starts as 5 bones but Starts as 5 bones but fuses together between fuses together between 18-3018-30

Triangular structure that Triangular structure that bears rows of dorsal sacral bears rows of dorsal sacral foraminaforamina

United with coxal bones at United with coxal bones at the sacroiliac joints.the sacroiliac joints.

Provides a guide for Provides a guide for determining the size of the determining the size of the pelvis.pelvis.

VertebraVertebra

SacrumSacrum

SacrumSacrum

Composed of 4 Composed of 4 bones that fuse bones that fuse together by age 25together by age 25

Forms the lowest Forms the lowest part of the part of the vertebral columnvertebral column

Acts a shock Acts a shock absorber when a absorber when a person sits.person sits.

VertebraVertebraCoccyxCoccyx

THORACIC CAGETHORACIC CAGE

Includes the ribs, Includes the ribs, thoracic vertebrae, thoracic vertebrae, sternum, and costal sternum, and costal cartilagescartilages

It supports the It supports the shoulder girdle and shoulder girdle and upper limbs, upper limbs, protects viscera, protects viscera, and functions in and functions in breathing.breathing.


RIBSRIBS 12 pairs of ribs are 12 pairs of ribs are

attached to the 12 attached to the 12 thoracic vertebraethoracic vertebrae

First 7 rib pairs are called First 7 rib pairs are called true ribstrue ribs, join the sternum , join the sternum directly by their costal directly by their costal cartilages. cartilages.

Remain 5 pairs called Remain 5 pairs called false ribsfalse ribs, their cartilages , their cartilages do NOT reach the do NOT reach the sternum directlysternum directly..


RIBSRIBS In fact the first 3 of the false ribs join the In fact the first 3 of the false ribs join the

cartilage of the 7cartilage of the 7thth true rib. true rib. The remain two ribs are called The remain two ribs are called floating floating

ribsribs, because they have no attachment , because they have no attachment to any cartilage. to any cartilage.

Typical rib has a shaft, head, and Typical rib has a shaft, head, and tubercle that articulate with the tubercle that articulate with the vertebrae.vertebrae.


SternumSternum is a flat is a flat elongated bone elongated bone that develops in that develops in three parts- an three parts- an upper upper ManubriumManubrium, a , a middle middle bodybody, and , and a lower a lower xiphoidxiphoid process. process.

Articulates with Articulates with costal cartilages costal cartilages and clavicles.and clavicles.

PECTORAL PECTORAL GIRDLEGIRDLE

Composed of 2 Composed of 2 clavicles (collar bone) clavicles (collar bone) and 2 scapulae and 2 scapulae (shoulder blades) (shoulder blades)

It forms an incomplete It forms an incomplete ring that supports the ring that supports the upper limbs and upper limbs and provides attachments provides attachments for muscles that move for muscles that move the upper limbsthe upper limbs


CLAVICLE Rodlike bones that run horizontally

between the sternum and shoulders. Hold shoulders in place and provide

attachments for muscles. Has a medial (sternal) end and a lateral

(acromial ends)



SCAPULA Broad, triangular bones Articulate with the humerus of each limb and

provides attachment for muscles of the upper limbs and chest.

Has a Acromion process that forms the tip of the shoulder

A Coracoid process that curves anteriorly and inferiorly to the clavicle.

Has a Glenoid cavity, it articulates with the head of the arm bone (humerus).

UPPER LIMBSUPPER LIMBS

Provide the frameworks and Provide the frameworks and attachments of muscles, and attachments of muscles, and function in levers that move function in levers that move the limb and its parts.the limb and its parts.

Humerus-Humerus-extends from scapula to extends from scapula to elbow.elbow.

Radius-Radius-Located on thumb side of Located on thumb side of the forearm between elbow and wristthe forearm between elbow and wrist

Ulna-Ulna-Longer than radius and Longer than radius and overlaps the humerus posteriorly.overlaps the humerus posteriorly.

Hand-Hand- Has a wrist, palm, and 5 Has a wrist, palm, and 5 fingersfingers

8 carpals that form a carpus, 5 8 carpals that form a carpus, 5 metacarpals, and 14 phalanges.metacarpals, and 14 phalanges.

UPPER LIMBSUPPER LIMBS

HUMERUSHUMERUS

Its upper end has a smooth round head Its upper end has a smooth round head that fits into the glenoid cavity. that fits into the glenoid cavity.

Below the head are two processes a Below the head are two processes a greater tuberclegreater tubercle on the lateral side and a on the lateral side and a lesser tuberclelesser tubercle on the anterior side. on the anterior side.

Near the middle of the bony shaft on the Near the middle of the bony shaft on the lateral side is a rough V-shaped area called lateral side is a rough V-shaped area called the the deltoid tuberositydeltoid tuberosity. .

On the bottom section of the humerous are On the bottom section of the humerous are EpicondylesEpicondyles which provide attachments which provide attachments for muscles and ligaments of the elbow. for muscles and ligaments of the elbow. (medial and lateral)(medial and lateral)

HUMERUSHUMERUS

HUMERUSHUMERUS

RadiusRadius

RadiusRadius--Located on thumb side of the Located on thumb side of the forearm between elbow and wrist.forearm between elbow and wrist.

Shorter than the ulnaShorter than the ulna A thick-disklike A thick-disklike head head at the upper endat the upper end On the radial shaft just below the head is a On the radial shaft just below the head is a

process called the process called the radial tuberosityradial tuberosity. An . An attachment for muscles.attachment for muscles.

At the distal end of the radius, a At the distal end of the radius, a lateral lateral styloid processstyloid process provides attachments for provides attachments for ligaments of the wrist.ligaments of the wrist.

Longer than radius and overlaps the Longer than radius and overlaps the humerus posteriorly.humerus posteriorly.

A A Medial StyloidMedial Styloid process at the process at the distal end of the ulna proves distal end of the ulna proves attachemnts for ligaments of the attachemnts for ligaments of the wrist. wrist.

The Ulna also has a The Ulna also has a headhead…on the …on the opposite side as the radiusopposite side as the radius

UlnaUlna

Remember….when thinking of Remember….when thinking of medial/lateral processes…you must medial/lateral processes…you must put your arms in the correct put your arms in the correct anatomical position! anatomical position!

Styloid Styloid Process Process

Radius and Radius and UlnaUlna

Wrist and HandWrist and Hand

The The wrist jointwrist joint is at the junction of is at the junction of the forearm and the hand. The the forearm and the hand. The skeleton of the wrist consists of 8 skeleton of the wrist consists of 8 small carpal bones that are firmly small carpal bones that are firmly bound in two rows of four bones bound in two rows of four bones each. The resulting compact mass is each. The resulting compact mass is called a called a carpuscarpus. .


• HandHand-- Has a palm, and 5 fingers. Has a palm, and 5 fingers. • Five Five metacarpals bonesmetacarpals bones, one in line with , one in line with

each finger, form the framework of the each finger, form the framework of the palm. These bones are cylindrical, with palm. These bones are cylindrical, with rounded distal ends that form the knuckles rounded distal ends that form the knuckles of clench fist. These bones are numbered 1-of clench fist. These bones are numbered 1-5 beginning with the metacarpal of the 5 beginning with the metacarpal of the thumb.thumb.


• HandHand-- Has a palm, and 5 fingers. Has a palm, and 5 fingers. • Phalanges are the finger bones. Phalanges are the finger bones.

There are three in each finger. A There are three in each finger. A proximal, a middle, and a distal proximal, a middle, and a distal phalanx and two in the thumb.phalanx and two in the thumb.


PELVIC GIRDLEPELVIC GIRDLE

The PG consists of The PG consists of 2 2 coxalcoxal bones bones (hipbones) that (hipbones) that articulate with each articulate with each other anteriorly and other anteriorly and with the sacrum with the sacrum posteriorly. Along with posteriorly. Along with sacrum and coccyx sacrum and coccyx they form the pelvis. they form the pelvis.

Provides support for Provides support for the weight, and the weight, and attachments for attachments for muscles, and protects muscles, and protects visceral organs.visceral organs.


Each coxae (hipbone) develops from Each coxae (hipbone) develops from three key parts. An ilium, an three key parts. An ilium, an ischium, and a pubis. ischium, and a pubis.

These parts fuse in the region of a These parts fuse in the region of a cup-shaped cavity called cup-shaped cavity called acetabulumacetabulum. .

This depression, on the lateral This depression, on the lateral surface of the hipbone receives the surface of the hipbone receives the rounded head of the femur.rounded head of the femur.


IlliumIllium- - largest portion of the coxal largest portion of the coxal bone, flares outward, forming the bone, flares outward, forming the prominence of the hip. prominence of the hip.

The margin of the prominence is The margin of the prominence is called the called the Iliac Crest.Iliac Crest.

Joins the sacrum at sacroiliac Joins the sacrum at sacroiliac jointjoint


IschiumIschium- Lowest - Lowest portion of the coxa portion of the coxa bones.bones.

L-shaped.L-shaped.


PubisPubis- constitutes - constitutes the anterior portion of the anterior portion of the coxa. the coxa.

The two pubic bones The two pubic bones come together at the come together at the midline to form a joint midline to form a joint called the smyphysis called the smyphysis pubis. pubis.

The angle these bones The angle these bones form below the form below the symphysis is the pubic symphysis is the pubic arch.arch.

PELVIC GIRDLEPELVIC GIRDLECOXA(E)COXA(E)

PELVIC GIRDLEPELVIC GIRDLEGreater and Lesser Greater and Lesser

PelvisPelvis

Below the pelvic brim; greater Below the pelvic brim; greater pelvis is above itpelvis is above it

Lesser pelvis functions as a Lesser pelvis functions as a birth canal; Greater pelvis birth canal; Greater pelvis helps support abdominal helps support abdominal organs.organs.

Female: Tilted forward, adapted for childbearing, cavity of the true pelvis is broad, shallow, and has a greater capacity.

Bones are lighter, thinner, and smoother The acetabula are smaller and farther apart The pubic arch is broader and more rounded. The sacrum are wider, shorter, sacral

curvature is accentuated. The coccyx more movable and much

straighter.

PELVIC GIRDLEPELVIC GIRDLEDifference: Male/FemaleDifference: Male/Female

Male: Tilted less far forward, adapted for support of a male’s heavier build and stonger muscles; cavity of the true pelvis is narrow and deep.

Bones are heavier and thicker; and markings are more prominent

The acetabula are larger and closer together. The pubic arch is more acute. The sacrum is narrow; longer; The coccyx less movable and curves

ventrally.

PELVIC GIRDLEPELVIC GIRDLEDifference: Male/FemaleDifference: Male/Female

LOWER LIMBSLOWER LIMBS

Provide the frameworks Provide the frameworks of the thigh, leg, and of the thigh, leg, and foot.foot.

FEMURFEMUR

FEMURFEMUR- Extends - Extends from the hip to from the hip to knee; Longest bone knee; Longest bone in the body.in the body.

A large, rounded A large, rounded headhead at its proximal at its proximal end which projects end which projects medially into the medially into the acetabulumacetabulum of the of the coxal bonecoxal bone

FEMURFEMUR

Just below the head are Just below the head are a constriction, or neck a constriction, or neck and two large processes.and two large processes.

A A greater trochantergreater trochanter and a and a lesser lesser trochantertrochanter. .

These processes provide These processes provide attachments for muscles attachments for muscles of the lower limbs and of the lower limbs and buttocks.buttocks.

FEMURFEMUR

• At the distal end of the femur are two At the distal end of the femur are two rounded processes, the rounded processes, the lateral and lateral and medial condylesmedial condyles, articulate with the tibia , articulate with the tibia of the leg.of the leg.

• On the medial surface at its distal end is a On the medial surface at its distal end is a prominent prominent medial epicondylemedial epicondyle, and on the , and on the lateral surface is a lateral surface is a lateral epicondylelateral epicondyle. . These projections provide attachments for These projections provide attachments for muscles and ligaments.muscles and ligaments.

FEMURFEMUR

FEMURFEMUR

PATELLAPATELLA

Flat seasamoid bone located in a Flat seasamoid bone located in a tendon that passes anteriorly over tendon that passes anteriorly over the knee.the knee.

Controls the angel of this tendon and Controls the angel of this tendon and functions in lever actions associated functions in lever actions associated with lower limbs movement. with lower limbs movement.

PATELLAPATELLA

TIBIA

AKA- Shin Bone, AKA- Shin Bone, Larger of the two Larger of the two leg bones.leg bones.

Located on the Located on the medial side of the medial side of the legleg

TIBIA

Its proximal end is expanded into Its proximal end is expanded into medial medial andand lateral condyleslateral condyles..

Below the condyles on the anterior surface Below the condyles on the anterior surface is a process called the is a process called the tibial tuberositytibial tuberosity. .

At its distal end, the tibia expands to form At its distal end, the tibia expands to form a prominence on the inner ankle called the a prominence on the inner ankle called the medial malleolusmedial malleolus, which is an , which is an attachment for ligaments. (Its lateral attachment for ligaments. (Its lateral cousin is on the fibula). cousin is on the fibula).

FibulaFibula

A long slender bone located A long slender bone located on the lateral side of the tibia. on the lateral side of the tibia.

Ends are slightly larger, with a Ends are slightly larger, with a proximal head and a distal proximal head and a distal lateral maleolus.lateral maleolus.

Ankle and Ankle and FootFoot

The foot is an The foot is an amazing and amazing and intricate structure. intricate structure. The bones in your The bones in your feet make up about feet make up about one-fourth of all one-fourth of all the bones in your the bones in your body. body.

Each foot contains Each foot contains 26 bones. It takes 26 bones. It takes 33 joints, 107 33 joints, 107 ligaments, 19 ligaments, 19 muscles and muscles and numerous tendons numerous tendons to hold the bones to hold the bones in place and to in place and to move in a variety move in a variety of ways.of ways.

Ankle and FootAnkle and Foot

In addition, each In addition, each foot has about foot has about 125,000 sweat 125,000 sweat glands that glands that excrete as much excrete as much as a half a pint as a half a pint of moisture each of moisture each day.day.


Consists of an Consists of an tarus, a metatarsus, tarus, a metatarsus, and five toes.and five toes.

The tarsus is The tarsus is composed of seven composed of seven tarsal bones. These tarsal bones. These bones are arranged bones are arranged so that one of so that one of them, the talus, can them, the talus, can move freely. move freely.

The largest of the tarsals, the The largest of the tarsals, the calcaneus or heel bone. It helps to calcaneus or heel bone. It helps to support the weight of the body and support the weight of the body and provides an attachment for muscles provides an attachment for muscles that move the foot. that move the foot.



The metatarsus The metatarsus consists of five consists of five elongated elongated metatarsal bones.metatarsal bones.

They are numbered They are numbered 1-5, beginning on 1-5, beginning on the medial side. the medial side.


The phalanges of the The phalanges of the toes are shorter, but toes are shorter, but otherwise similar to otherwise similar to those of the fingers, those of the fingers, and align, and and align, and articulate with the articulate with the metatarsals.metatarsals.

Each toe has three Each toe has three phalanges, a proximal, phalanges, a proximal, a middle, and distal a middle, and distal phalanx- except the big phalanx- except the big toe which only has the toe which only has the first two. first two.

How well How well can you do? can you do?

On a scrape On a scrape piece of piece of paper take paper take this mini-this mini-quiz!quiz!

How did you How did you do???do???

Documents

Skeletal System Part B. VERTEBRAL COLUMN Extends from the skull to the pelvis and protects the spinal cord. Extends from the skull to the pelvis and