Bio210 Lecture 5: The Appendicular Skeleton

Front 1

The Clavicles:
Acromial End

Back 1

S shaped bones that connect to sternum on pyramid shaped sternal end and scapula on acromion via wider acromial end.

sternoclavicular joint is the only connection of axial skeleton to pectoral girdle.

the clavicles are very fragile, easy to fracture if fall with hands stretched out but heal fast

used to be a dermal bone but became endochondreal

can survive without it, least important joint in shoulder girdle

Front 2

The Scapula:
coracoid process, acromion and spine, Supraspinous and Infraspinous fossae, Glenoid cavity

Back 2

Glenoid Cavity is the surface area for attachment of humerus

Coracoid process - small anterior projection, hook-like, only remnant of old anterior and posterior corocoids, make shoulder girdle moveable due to soft tissue and clavicle

Acromion - larger projection that articulates to the clavicle, forming acromioclavicular joint

(both coracoid process and acromion are attached to ligaments and tendons associated with the shoulder joint)

Scapular Spine - continuous with the acromion and medial border, divides the posterior surface of the scapula into two regions

Supraspinous fossa the region above the spine

Infraspinous fossa - region below spine (larger SA)

Front 3

How many groups of bones are in the appendicular skeleton?

Back 3

4: Pectoral Girdle, Upper (fore) Limb, Pelvic Girdle, Lower (hind) Limb

Front 4

Pectoral Girdle

Back 4

Scapulae and Clavicles

Front 5

Upper Limb

Back 5

Humerus, Ulna, Radius, Manus

Front 6

Humerus:
head, greater tubercle, anatomical neck, shaft, condyle with capitulum and trochlea, medial and lateral epicondyles

Back 6

head - articulates with the glenoid cavity of the scapula

greater tubercle - est lateral contour of shoulder

anatomical neck - where joint capsule ends

medial and lateral epicondyles - develop proximal to an articulation, provide additional surface area for muscle attachment

Condyle with capitulum and trochlea - attachment area for ulna and radius

Front 7

Humerus:
head, greater tubercle, anatomical neck, shaft, condyle with capitulum and trochlea, medial and lateral epicondyles

Back 7

head - articulates with the glenoid cavity of the scapula

greater tubercle - est lateral contour of shoulder

anatomical neck - where joint capsule ends

medial and lateral epicondyles - develop proximal to an articulation, provide additional surface area for muscle attachment

Condyle with capitulum and trochlea - attachment area for ulna and radius

Front 8

Humerus:
head, greater tubercle, anatomical neck, shaft, condyle with capitulum and trochlea, medial and lateral epicondyles

Back 8

head - articulates with the glenoid cavity of the scapula

greater tubercle - est lateral contour of shoulder

anatomical neck - where joint capsule ends

medial and lateral epicondyles - develop proximal to an articulation, provide additional surface area for muscle attachment

Condyle with capitulum and trochlea - attachment area for ulna and radius

Front 9

Humerus:
head, greater tubercle, anatomical neck, shaft, condyle with capitulum and trochlea, medial and lateral epicondyles

Back 9

head - articulates with the glenoid cavity of the scapula

greater tubercle - est lateral contour of shoulder

anatomical neck - where joint capsule ends

medial and lateral epicondyles - develop proximal to an articulation, provide additional surface area for muscle attachment
*epicondyles are used for muscle leverage (large in bears and moles - digging etc)

Condyle with capitulum and trochlea - attachment area for ulna and radius

Front 10

Ulna:
olecranon, trochlear notch, radial notch, proximal radioulnar joint, distal radioulnar joint, styloid process of ulna

Back 10

olecranon - superior end of ulna, point of elbow, extends to olecranon fossa of humerus when stretch arm out

trochlear notch - articulates with the trochlea of the humerus (elbow joint)

radial notch - smooth, accommodates head of the radius (where proximal radioulnar joint is)

distal radioulnar joint - so radius and ulna can coordinate

styloid process of ulna - attachment site for wrist bones (cartilage separating them)

Front 11

Radius:
radial head, radial tuberosity, ulnar notch, styloid process

Back 11

radial head - disc-shaped, articulates with the capitulum of humerus

ulnar notch - site of articulation for ulna head (distal portion of radius)

styloid process - radius and ulna articulate to wrist bones on distal end, styloid of radius stabilizes this

radial tuberosity - attachment site for biceps brachii muscles

Front 12

Manus

Back 12

there's curvature in hand for locomotion, convex, complex bones to move wrist in many ways

8 carpal bones: 4 proximal, 4 distal

metacarpal bones - support the hand, connect with distal carpal bones

phalanges - 14 finger bones (each finger has 3 phalanges proximal, middle, distal + pollex - thumb, first finger, 2 phalanges)

Front 13

Carpal Bones

Back 13

"Sam Likes To Push The Toy Car Hard" (linear order NOT circular)

(start at proximal thumb) Scaphoid, Lunate, Triquetrum, Pisiform, Trapezoid, Capitate, Hamate (end between digit 4 and 5)

Front 14

Metacarpals and Phalanges

Back 14

Metacarpals are numbered I - V from the thumb to the pinky BUT remember they support the hand (in palm area)

Phalanges - actual fingers, proximal = closest to metacarpals, middle, distal = finger tips

phalangial formula of 2, 3, 3, 3, 3

Front 15

The Pelvic Girdle

Back 15

consists of two hip bones (coxal bones or ox coxae)

a coxal bone/ox coxae is divided into ilium (top), ischium (widers bottom) and pubis (thinner bottom)

Front 16

Ilium

Back 16

articulates with the sacrum via auricular surface for articulation with sacrum

Front 17

Acetabulum

Back 17

forms the concave socket where femur head inserts itself via lunate surface of acetabulum.

easy to dislocate between acetabulum and femur because it's shallow.

it's a very large, weight bearing region

ilium, ischium and pubis come together at acetabulum

Front 18

ischial spine and ischial tuberosity

Back 18

ischial spine is located above the lesser sciatic notch and the ischial tuberosity is below the lesser sciatic notch

the ischial tuberosity is a projection that carries the weight of your body while sitting down

Front 19

obturator foramen

Back 19

a space closed by a sheet of collagen for hip muscle attachment

Front 20

pubic symphysis

Back 20

the two pubic bones attach via median fibrous cartilage pad to make pelvic bone

Front 21

The Lower Hind Limb

Back 21

Femur, Tibia and Fibula and Pes - tarsus

Front 22

Femoral head

Back 22

rounded epiphysis that articulates to the acetabulum of the pelvis

Front 23

Neck and shaft

Back 23

neck joins shaft at an angle (125 degrees)

Front 24

Greater and lesser trochanters

Back 24

located at junction between neck and shaft.

large tendons attach to femur here

massive weight bearing muscles attach as well

Front 25

medial and lateral epicondyles,
medial and lateral condyles,
intercondylar fossa

Back 25

medial and lateral epicondyles form superior to medial and lateral condyles which participate in the knee joint

the medial and lateral condyles are separated by a deep intercondylar fossa and on the anterior surface are separated by patellar surface which is a smooth articulation where patella glides against.

medial epicondyle is for back and forth movement only therefore not as large

Front 26

popliteal surface

Back 26

even deeper than intercondylar fossa

Front 27

patella

Back 27

large sesamoid bone that forms within the tendon of the quadriceps femoris - knee cap

Front 28

medial and lateral tibial condyles

Back 28

articulate with medial and lateral condyles of the femur

Front 29

medial malleolus

Back 29

a large projection at the end of the tibia, supports joint between tibia and ankle

Front 30

fibula:
lateral malleolus

Back 30

provides lateral stability to the ankle, fractures easily (pott fracture) if too much pressure on it

Front 31

The Tarsal Bones

Back 31

Seven tarsal bones:

"Tom Can Control Not Much In Life"

Talus, Calcaneus, Cuboid, Navicular, Medial cuneiform, Intermediate cuneiform, Lateral cuneiform

Front 32

Talus, Calcaneus

Back 32

Talus - transmits weight from tibia toward the toes

Calcaneus - heel bone, largest of the tarsal bones, when standing the weight is transmitted from tibia to talus to calcaneus to ground

Front 33

Cuboid and Cuneiform bones

Back 33

articulate with the metatarsal bones

Front 34

Metatarsal bones and Phalanges

Back 34

Metatarsals support foot, labeled I-V from hallux (big toe) to pinky toe BUT REMEMBER it's NOT your toes!

Your toes are the phalanges - Hallux - big toe, same phalangical formula as hands - 2, 3, 3, 3, 3 - proximal, middle and distal phalanx

Front 35

Longitudinal Arch and Transverse Arch

Back 35

Longitudinal Arch - elevates surface of the feet, prevents muscles, veins and blood vessels from being squished by the metatarsal bones and the ground. Never developing a longitudinal arch or losing it causes flat feet.

Transverse Arch - from medial to lateral borders of the foot.
Resistance to motion so can bounce, flexible not break foot.
Bunions are caused by a loose transverse arch.