Appendicular Skeleton. Allows us to move and manipulate objects Includes all bones besides axial skeleton: the limbs the supportive girdles.

Appendicular Skeleton

Allows us to move and manipulate objects

Includes all bones besides axial skeleton:• the limbs • the supportive girdles

Pectoral Girdle

Also called the shoulder girdle

Connects the arms to the body

Positions the shoulders

Provides a base for arm movement Consists of the scapula (shoulder

blade) and the clavicle (collarbone)

Scapula (shoulder blade) Features to know

• Scapular spine• Acromion process• Corocoid process• Glenoid cavity (glenoid fossa)• Borders – superior, medial, lateral• Corners – superior angle, inferior angle,

lateral angle

Clavicle• S-shaped bones• Run from the manubrium to the acromion

on the scapula

Upper Limb

Consists of arms, forearms, wrists, and hands

Note: arm (brachium) = 1 bone, the humerus

Humerus• Also called the arm • The long, upper armbone• Articulates with the pelvic girdle and

forearm

Humerus Features

• Head – articulates with glenoid fossa• Medial and lateral epicondyles• Trochlea – articulates with ulna• Capitulum – articulates with radius• Olecranon fossa

Forearm• Consists of 2 long bones:

ulna (medial) Olecranon process

radius (lateral)

Wrist 8 carpal bones:

• 4 proximal carpal bones (starting Laterally) Scaphoid bone Lunate bone Triquetrum Pisiform bone

• 4 distal carpal bones (starting Laterally) Trapezium: Trapezoid bone: Capitate bone: Hamate bone:

Hand (Metacarpals)• 5 long bones of the hand • Numbered I–V from lateral (thumb) to

medial

Fingers/Thumb• Pollex (thumb):

2 phalanges (proximal, distal) • Fingers:

3 phalanges (proximal, middle, distal)

Pelvic Girdle

Os Coxae Made up of 3 fused bones:

• ilium (articulates with sacrum)• ischium• pubis

Differences• Also called the hip socket• Is the meeting point of the ilium, ischium,

and pubis • Is on the lateral surface of the os coxae • Articulates with head of the femur (lunate

surface)

Ilium• Iliac crest• Anterior superior iliac spine (ASIS)• Posterior superior iliac spine (PSIS)

Ischium• Ischial tuberocity

Pubis• Pubic symphysis

Differences between male and female pelvic girdles.

Female pelvis:• smoother• lighter• less prominent muscle and ligament attachments

Modifications for Childbearing Enlarged pelvic outlet Broad pubic angle (> 100°) Less curvature of sacrum and coccyx Wide, circular pelvic inlet Broad, low pelvis Ilia project laterally, not upwards

Lower Limb

Consists of:• Femur (thigh)• Patella (kneecap)• Tibia and fibula (leg)• Tarsals (ankle)• Metatarsals (foot)• Phalanges (toes)

Femur• Largest, heaviest bone• Features

Head – articulates with acetabulum Neck Greater trochanter Medial and lateral epicondyles:

above the knee joint Medial and lateral condyles:

form part of knee joint

Patella (knee cap)• A sesamoid bone• Formed within tendon of quadriceps

muscles

Tibia (shin bone)• Medial bone in lower leg• Supports body weight• Features

Medial and Lateral Condyles Tibial tuberosity Medial Malleolus – medial “ankle bone”

Fibula• Lateral bone in lower leg• Does not support body weight• Features

Head Lateral Malleolus – lateral “ankle bone”

Ankle (Tarsus) Consists of 7 tarsal bones Talus Calcaneus (heel bone) Cuboid bone Navicular bone Medial cuneiform Intermediate cuneiform Lateral cuneiform

Feet (Metatarsals)• 5 long bones of foot • Numbered I–V, medial to lateral

Toes (phalanges) • Hallux:

big toe, 2 phalanges (distal, proximal)• Other 4 toes:

3 phalanges (distal, medial, proximal)

Feet Arches Arches transfer weight from 1 part of

the foot to another• Longitudinal arch• Transverse arch

Pes planus – flat arches Pes cavus – high arches