Appendicular Skeleton (126 bones) Chapter 5 Appendicular Skeleton (126 bones)

Shoulder Girdle – aka Pectoral Girdle 2 bones Clavicle – collarbone Attaches to manubrium and scapula Helps form shoulder joint – holds shoulder away from thorax Scapula – shoulder blades Acromion – joins clavicle at acromioclavicular joint Coracoid process – anchors muscles Glenoid cavity – socket for humerus

Only directly connected to axial skeleton at sternoclavicular joint Allow for easy scapula movement – but is easily dislocated

Upper Limb Arm – humerus Head – joins scapula at glenoid cavity Greater/lesser tubercles – muscle attachment Deltoid tuberosity – ½ way down – deltoid attachment Trochlea and capitulum – join forearm Coronoid and olecranon fossas – allow elbow movement

Forearm Radius Ulna Connected by interosseous membrane Lateral – on thumb side with palm out Head joins capitulum Radial tuberosity – bicep attachment Ulna Medial – on little finger side with palm out Coronoid and olecranon processes surround trochlea Connected by interosseous membrane Styloid process on distal end of both

Hand Carpals – carpus (wrist) – 2 irregular rows of 4 bones each Metacarpals – palm - #1-5 from thumb Phalanges – fingers – 14 bones 3 in fingers, 2 in thumbs

Pelvic Girdle 2 coxal bones – aka ossa coxae – hip bones When combined with sacrum and coccyx = pelvis Attach securely to axial skeleton Bear weight of upper body Protect reproductive organs, bladder, large intestines

Formed from 3 fused bones Ilium Connects to sacrum at sacroiliac joint Upper edge – iliac crest Ischium Inferior (bottom) portion Ischial tuberosity – receives weight when sitting Pubis – pubic bone Pubic symphysis – cartilaginous anterior joint btw the pubic bones – forms pubic arch All 3 fuse at acetabulum – socket for femur

2 regions False pelvis – medial to flaring portions of ilia True pelvis – inferior to ilia – surrounded by bone Male and female slightly differ Female is adapted for childbirth

Lower Limbs Thigh – femur Greater/lesser trochanters – muscle attachment Joins hips at acetabulum – held tightly Lateral and medial condyles – join tibia Separated by intercondylar fossa Patellar surface – joint w/ patella

Leg Tibia – shinbone – medial Medial and lateral condyles join femur Separated by intercondylar eminence Tibial tuberosity – patellar ligament joins Medial malleolus – inner bulge of ankle Fibula – very thin Lateral malleolus – outer bulge of ankle

Foot Tarsals – tarsus – 7 bones Posterior ½ of foot Weight carried by 2 largest Calcaneus – heelbone Talus – btw tibia and calcaneus Metatarsals – sole – 5 bones Phalanges – toes – 14 bones Toes have 3 each, big toe has 2