Anatomy and Physiology / Unit 4: The Skeletal System
4.5 The Appendicular Skeleton
Notes
The appendicular skeleton (126 bones) includes the limbs and the girdles that attach them.
- Pectoral girdle: clavicle and scapula (very mobile, loosely attached to the axial skeleton). Upper limb: humerus, radius (thumb side), ulna (pinky side), 8 carpals, 5 metacarpals, 14 phalanges.
- Pelvic girdle: two hip bones (os coxae), each formed from ilium, ischium and pubis; with the sacrum and coccyx it forms the pelvis. Strong and stable for weight bearing. The female pelvis is wider and more shallow, adapted for childbirth.
- Lower limb: femur (longest, strongest), patella, tibia (shin, weight bearing), fibula (lateral, thin), 7 tarsals (the largest is the calcaneus, the heel), 5 metatarsals, 14 phalanges.
- Total: 80 axial + 126 appendicular = 206 bones.
Practice
Which bone of the forearm is on the thumb side in anatomical position?
In anatomical position the radius is lateral, on the thumb side.
Which bone is the longest and strongest in the body?
The femur (thigh bone) is the longest and strongest.
Which statement about the pectoral girdle is correct?
The clavicle and scapula are mobile. The ilium, ischium and pubis form the hip bone.
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