Presentation is loading. Please wait.

Presentation is loading. Please wait.

The Appendicular Skeleton

Similar presentations

Presentation on theme: "The Appendicular Skeleton"— Presentation transcript:

1 The Appendicular Skeleton

2 THE SKELETAL SYSTEM The Appendicular Skeleton
2 pairs of limbs and 2 girdles Pectoral (shoulder) girdle attaches upper limbs Pelvic (hip) girdle secures lower limbs 3-Segmented limbs Upper = arm Arm Forearm Hand Lower = leg Thigh Leg Foot

3 Pectoral Girdle (Shoulder Girdle)
Clavicle – anterior: collar bone Sternal end attaches to the manubrium medially Acromial end articulates with the scapula laterally Scapula – posterior: shoulder blade

4 Scapulae: triangular, paired, but don’t connect in back (adds thoracic flexibility)

5 Scapula Glenoid cavity articulates with the humerus
Acromium articulates with clavicle Coracoid process projects anteriorly

6 Upper extremity Arm or Brachium = upper arm Forearm or Antebrachium
Between shoulder and elbow (humerus) Forearm or Antebrachium Radius & ulna Hand includes: Wrist (carpus) Palm (metacarpus) Fingers (phalanges)

7 Arm Humerus is the only bone
Head of humerus fits into glenoid cavity of scapula Distal & medially, trochlea articulates with the ulna Distal & laterally capitulum articulates with the radius Medial & lateral epicondyles

8 Right humerus, anterior view

9 Right humerus, posterior view

10 Forearm 2 bones: articulate with each other proximally and distally
Radius is thinner proximally, like a spool of thread, and wide distally; ulna is slightly longer and looks like a monkey wrench (supposedly!) 2 bones: articulate with each other proximally and distally Interosseous membrane between them Ulna Olecranon hinges with the humerus forming elbow Styloid process distally Radius Contributes to wrist joint Styloid process anchors a ligament to wrist (thumb side)

11 Right forearm bones, anterior view

12 Right forearm bones, posterior view

13 In the anatomical position, the radius is lateral (thumb side); with pronation the palm faces posteriorly and the bones cross Left forearm Anatomical position Prone: body lying face down Suppine: body lying face up prone (you can remember prone if you think about how you would fall forward onto your face if you passed out) pronation moves the forearm into the prone position and supination moves it back to the anatomical position

14 Proximal and distal joints of the forearm
proximal ulna

15 Hand Proximal is “wrist” – 8 carpal bones Palm of hand - 5 metacarpals
Fingers (or digits) consist of miniature long bones called phalanges: thumb (“pollex”) has 2; fingers have 3: proximal, middle, distal Right hand, 2 views:



18 Pelvic Girdle (Hip Girdle)
Strongly attached to axial skeleton (sacrum) Deep sockets More stable than pectoral (shoulder) girdle Less freedom of movement Made up of the paired hip bones “Bony pelvis” is basin-like structure: hip bones plus the axial sacrum and coccyx

19 Hip bone (os coxae): 3 separate bones in childhood which fuse
Ilium Ischium Pubis

20 Ilium Iliac crest Anterior superior iliac spine Greater sciatic notch
Forms part of “acetabulum” (hip socket) which receives ball-shaped head of femur ilium

21 Ischium Body Ramus Ischial spine Ischial tuberosity Part of socket

22 Pubis Joins medially in pubic symphysis
Forms “obturator foramen” (large hole) with ischium Part of socket pubis pubis

23 Hip bones with labels

24 False (greater) and true (lesser) pelvis Ligaments

25 Pelvis and childbearing
Male/female differences Large & heavy vs light & delicate Heart shaped pelvic inlet vs oval Narrow deep true pelvis vs wide & shallow Narrow outlet vs wide Less than 90 degree pubic arch vs more than 90 degree Birth canal changes shape as baby descends: head turns ¼ Higher: pelvic inlet (brim) - side to side largest Lower: pelvic outlet - largest in AP direction

26 Lower limb Thigh: femur Leg (lower leg) Tibia Fibula Foot

27 Thigh Femur is largest, longest and strongest bone in the body
Head fits in socket (acetabulum) of pelvis Neck is weakest Greater trochanter Distal: lateral & medial condyles and epicondyles Patella: sesmoid bone

28 Right femur, anterior view

29 Right femur, posterior view

30 Leg Tibia: shin bone Fibula Interosseous membrane
Medial and lateral condyles Tibial tuberosity Distal medial malleolus (medial ankle) Fibula Distal lateral malleolus (lateral ankle) Interosseous membrane

31 Right lower leg, anterior view


33 Foot Tarsus: 7 tarsal bones 5 metatarsals 14 phalanges
Talus: articulates with tibia and fibula anteriorly and calcaneus posteriorly Calcaneus: heel bone Smaller cuboid, navicular, and 3 cunieforms (medial, intermediate and lateral) 5 metatarsals 14 phalanges Great toe is hallux

34 Right foot, superior (dorsal) view and inferior (plantar) view

35 Right foot, lateral and medial views

36 Arches

Download ppt "The Appendicular Skeleton"

Similar presentations

Ads by Google