Appendicular Skeleton Appendicular Skeleton 126 bones suspended by

Appendicular Skeleton

Appendicular Skeleton • 126 bones – suspended by girdles from axial skeleton • Designed for movement • Pectoral girdle – 4 bones • Upper extremity -Arm – 1 bone - forearm – 2 bones - hand = wrist, palm & fingers – 27 bones [each]

• Pelvic Girdle – 2 bones • Lower Extremity – leg – 1 bone - lower leg – 2 bones - foot = ankle, instep & toes – 26 bones [each ] - Patella – 2 bones *Pelvic or Hip Girdle: • Attaches the lower extremity to the axial skeleton • Provides support for body weight

Hip / Coxal bones [ ossa coxae, innominate bones] Ilium – ASIS, PSIS Ischium - tuberosity Pubis - rami Symphysis pubis Obturator foramen Acetabulum

Lower Extremity • Leg [thigh] – femur Head Fovea capitis Neck Trochanters – greater/lesser Condyles – medial/lateral Epicondyles

Lower Extremity *Leg – region between knee and ankle • Fibula – lateral bone • Tibia – medial bone Malleolus Condyles – medial/lateral Tibial tuberosity

Patella [kneecap] a flat, triangular sesamoid bone Enclosed within the quadriceps tendon

Ankle or Tarsus Contains 7 tarsal bones Calcaneous = heel bone Talus Cuboid Navicular Cuneiforms – lateral, intermediate & medial

Foot • Metatarsals – not named, but numbered 1 – 5 starting at medial side • Toes – phalanges or digits: 3 bones [proximal, distal & middle] for each toe, except big [great] toe which has 2 [no middle phalanx]

Pectoral or Shoulder Girdle • Clavicle [collarbone] – ‘S’ shaped bone * most frequently fx’d bone of body • Scapula [shoulder blade] – thin, flat, triangular bone. Acromion Spine Coracoid process Gleniod fossa/cavity

Upper Extremity • Arm [brachium] humerus Head Tubercles – greater/lesser Epicondlyes – medial/lateral Olecranon fossa Capitulum Trochlea

Upper Extremity *forearm – region between elbow and wrist • Ulna Olecranon process • Radius head Styloid process

Wrist or Carpus • Contains 8 carpal bones Bound tightly by ligaments Arranged in 2 rows Scaphoid Trapezium Lunate Trapezoid Triquetral Capitate Pisiform Hamate

Hand • Metarcarpals – not named, but numbered 1 -5 starting on lateral [thumb] side • Fingers – phalanges or digits: 3 bones [proximal, distal & middle] for each finger, except thumb, which has 2 [ no middle phalanx]