Master Bone Count Reference
TOTAL ADULT HUMAN BONES = 206
Axial Skeleton (80 bones)
| Component | Count | Details |
|---|---|---|
| Skull | 22 | 8 cranial + 14 facial |
| Vertebral column | 26 | C7 + T12 + L5 + Sacrum (1 fused) + Coccyx (1 fused) |
| Ribs | 24 | 12 pairs (7 true + 3 false + 2 floating) |
| Sternum | 1 | Manubrium + body + xiphoid process |
| Hyoid | 1 | ONLY bone not articulating with any other bone |
| TOTAL | 80 |
Appendicular Skeleton (126 bones)
| Component | Count |
|---|---|
| Pectoral girdle (2 clavicles + 2 scapulae) | 4 |
| Upper limbs (30 per side × 2) | 60 |
| Pelvic girdle | 2 |
| Lower limbs (30 per side × 2) | 60 |
| TOTAL | 126 |
CHECK: 80 + 126 = 206 ✓
Vertebral Formula (Memorize!)
- Cervical: C7 (neck; C1=atlas, C2=axis)
- Thoracic: T12 (chest; articulate with ribs)
- Lumbar: L5 (lower back; largest, most robust)
- Sacrum: S1 (5 fused vertebrae, 1 bone)
- Coccyx: Cx1 (3-4 fused vertebrae, 1 bone)
- 7 + 12 + 5 + 1 + 1 = 26 vertebral bones
Rib Classification
- True ribs (1-7): 7 pairs, attach directly to sternum via own costal cartilage
- False ribs (8-10): 3 pairs, cartilage joins the rib above (not directly to sternum)
- Floating ribs (11-12): 2 pairs, NO anterior attachment
- TOTAL: 24 ribs = 12 pairs
NEET Special Facts
- Hyoid: Only non-articulating bone; part of axial skeleton; supports tongue
- Newborns have ~270-300 bones (many fuse to reach adult 206)
- Sesamoid bones (e.g., patella) are embedded in tendons; patella = largest sesamoid