Chapter 8 | The Appendicular Skeleton | Exam 2 | USF

The Appendicular Skeleton has how many bones?

126 bones

What is included in the Appendicular skeleton?

The upper & lower limbs

Pectoral Girdle does what?

Attaches the upper limbs to the tru

Pelvic Girdle does what?

Attaches the lower limbs to the trunk

Upper & Lower limbs differ in function but..

share the same structural plan

What does the pectoral girdle include?

The clavicle and scapula

Pectoral girdle provide what?

attachment for many muscles that move the upper limb

How would you describe the pectoral girdle?

very light and upper limbs are mobile

What is the bone that articulates with the axial skeleton?

The clavicle

How would you describe the socket of the shoulder joint?

Shallow

What’s another name for the shoulder joint?

Glenoid cavity

A shallow socket is good for what?

Flexibility but bad for stability.

The Clavicle sternal end articulates with the ____.

Manubrium

The Clavicle acromial end articulates with the ___.

Scapula

What are the purposes for the clavicles?

-Provide attachment for muscles

-Hold the scapulae & arms laterally

-Transmit compression forces (upper limbs → axial skeleton)

How would you describe a Scapulae?

Thin, triangular bones located on the dorsal surface of rib cage

What are the 3 borders to a scapulae?

Superior, Medial, Lateral

What are the 3 angles of the Scapulae?

Lateral, Superior, Inferior

What two things form the shoulder joint?

Glenoid cavity with humerus

How many bones does the upper limb have?

30 bones from each upper limb

The only bone of the arm?

Humerus

How would you describe the humerus?

The longest and strongest bone of the upper limb. Articulates with scapula, radius, & ulna.

Many structures of the humerus provide what?

Sites for muscle attachment and others provide articulation sites for other bones

What are the distal features of the humerus?

Trochlea, Capitulum, Medial & lateral epicondyles, the coronoid, olecranon, & radial fossae

What makes up the forearm?

The radius and ulna

What does the forearm articulate with?

Proximal with humerus, distal with carpals

Radius and Ulna articulate with each other because of what joint?

The radioulnar joint

What interconnects the radius and ulna?

The interosseous membrane

What is the main bone that forms the elbow joint with humerus?

Ulna

What separates the Ulna distal end and carpals?

Fibrocartilage

Ulna landmarks:

• Olecranon

• Radial Notch

• Trochlear notch

• Coronoid process

• Ulnar styloid process

What does the superior head of radius articulate with on the humerus?

The Capitulum

What bone contributes heavily to the wrist joint?

The Radius because the hand moves when the radius moves

Major landmarks of the radius:

• head

• neck

• radial tuberosity

• radial styloid process

What forms the true wrist?

The carpus

What happens between the carpals?

Gliding movements

How much bones are in the carpus?

8 marble sized bones

What phrase helps you know the carpal bones?

“Sally left the party to take Camen home”

What bones form the palm?

Metacarpals

Each finger expect which one has proximal, middle, and distal phalanges?

The thumb has no middle.

What is pelvic girdle known for?

Weight barring and supporting visceral (gut) organs

The pelvic girdle has what type of socket?

A deep cup-shaped socket (acetabulum)

The Pelvic girdle does what for movement?

Lower limbs have less freedom of movement

What does the pelvic girdle include?

Hip bones (coxal/pelvic) & the sacrum

What three separate bones does the pelvic girdle consist of in childhood?

Ilium, Ischium, & Pubis

What is the structure that is very weight barring?

Acetabulum

The Ilium is what?

The flaring bone that is superior. It is the site of attachment for many muscles

What is the articulation with the sacrum and ilium called?

The sacroiliac joint

What does the Ischium join anteriorly with?

The pubis

What is the strongest part of the hip bone?

Ischial tuberosities

What is the Pubic Symphysis?

2 pubic bones joined by fibrocartilage at the midline

What is the Pubic arch?

Inferior to the pubic symphysis and the angle helps distinguish male from female pelvis

What regions the pelvis divided into?

False and true pelvis

What is the False pelvis?

Bounded by alae of the iliac bones. It is on top.

What is the true pelvis?

Inferior to pelvic brim and forms a bowl containing pelvic organs.

What separates the false and true pelvis?

The pelvic brim

How would a female pelvis be different than a males?

Female pelbis is wider, shallower, & lighter

Describe the Pelvic inlet

Delineated by pelvic brim & largest in diameter right to left

Describe the Pelvic outlet

Inferior margin of true pelvis & largest in diameter anteroposteriorly

What carries the entire weight of the erect body?

The lower limb

What bone is in the thigh?

Femur

What is the longest and strongest bone of the body?

The Femur

What direction does the femur curve to?

The midline for better balance and strength

What type of bone is the Patella?

A triangular sesamoid bone

What is the patella embedded in?

The tendon that secures the quadriceps muscles which then protects the knee

This improves leverage of the thigh muscle across the knee?

The patella

What is the leg made up of?

The tibia and fibula

Which bone receives weight of the body from the femur?

The Tibia

What connects the Tibia & Fibula?

Interosseous membrane (dense connective tissue)

-allow almost no movement

What are the 3 arches the foot has?

Medial longitudinal, lateral longitudinal, and transverse

What do the arches of the foot do?

Distribute body weight and provide resilience

What are the important functions of the foot?

-Support body weight

-acts as lever to propel body forward

-segmentation makes foot pliable & adapted to uneven ground

How many bones does the tarus have?

7 bones

Where is the body weight in the tarus primarily?

The Talus & Calcaneus

What is the trochlea of the talus?

It is the site of articulation with the tibia

How many Metatarsus?

5 small long bones

What is the great toe called?

The hallux

How many phalanges of the toes are there?

14 phalanges

How are the arches maintained in the foot?

-Interlocking shapes of tarsals

-Ligaments & tendons