骨骼系统的疾病 　 脊 柱 强 直 症 颈 椎 退 化 骨 质 疏 松 症 Skeletal System 　 1. Skull 2. Sternum 3. Ribs 4. Vertebrae 5. Sacrum 6. Lower Limb Bones 7. Supporting Bones (Hip) 8. Upper Limb Bones 9. Supporting Bones (Scapula and Collarbone)