Anatomy & Physiology: Organization of the Skeleton

The bones of the body are categorized into two groups, the axial skeleton and the appendicular skeleton . The bones of the axial skeleton revolve around the vertical axis of the skeleton, while the bones of the appendicular skeleton make up the limbs that have been appended to the axial skeleton. A list of the bones in the axial and appendicular skeletons is given in Tables 1 and 2 , respectively. Major bones of both skeletons are shown in Figure 1 .

Figure 1

Major bones of the axial and appendicular skeletons.

TABLE 1

Axial Skeleton Bones (80 Bones)

General Description	Name of Bone	No. of Bones	Additional Information
cranium (8)	frontal	1
	parletal	2
	temporal	2
	sphenoid	1
	ethmoid	1
	occipital	1
facial bones (14)	mandible	1	lower jawbone
	maxilla	2	upper jawbone
	zygomatic bone	2	cheek bones
	nasal bone	2
	lacrimal bone	2
	palatine	2
	inferior nasal concha	2
	vomer	1
hyoid	hyoid	1
ear ossicles	malleus, incus, stapes	6	2 each
vertebral column (26)	cervical vertebrae	7	C₁-C₇
	thoracic vertebrae	12	T₁-T₁₂
	lumbar vertebrae	5	L_1-L₅
	sacrum	1	5 fused S₁ - S₅
	coccyx	1	4 fused
thorax (thoracic cage or bony thorax)	sternum	1
	true ribs (7 pair)	14	vertebrosternal
	false ribs (3 pair)	6	vertebrochondral
	false ribs (floating ribs)	4	vertebral ribs

TABLE 2

Appendicular Skeleton Bones (126 Bones)

General Description	Name of Bone	No. of Bones	Additional Information
pectoral girdle	clavicle	2	collarbone
(shoulder girdle)	scapula	2	shoulder blade
*upper limb (60)*	*humerus*	2	*1 per arm*
	*ulna*	2	*1 per forearm*
	*radius*	2	*8 per wrist*
	*carpals (16)*
	*1. scaphoid*	2
	*2. trapezium*	2
	*3. capitate*	2
	*4. trapezoid*	2
	*5. lunate*	2
	6. triquetrum	2
	7. pisiform	2
	8. hamate	2
	metacarpals	10	5 in each arm
	phalanges	28	3 per digit (pollex has 2)
pelvic girdle	coxal bones (os coxae)	2	hip bones
(hip) (2)	1. ilium
	2. ischium		(3 fused pairs)
	3. pubis
lower limb (60)	femur	2
	patella	2
	tibia	2
	fibula	2
lower limb (60)	tarsal (14)
1. talus	2
2. calcaneus	2
3. cuboid	2
4. navicular	2
5. medial cuneiform	2
6. interm. cuneiform	2
7. lateral cuneiform	2
lower limb (60)	metatarsals	2	5 per foot
	phalanges	2	3 per toe (hallux has 2)