Lecture Notes: Classifications of Bones in the Skeleton

Overview of Skeleton

• Axial Skeleton

  • Includes the skull, vertebral column, thoracic cavity (ribs and sternum)

• Appendicular Skeleton

  • Includes bones of the arms, legs, shoulder, and pelvis

Bone Classifications

Irregular Bones

• Vertebrae
  • Unusually shaped, part of the vertebral column
• Coxal Bone
  • Large pelvic bone, includes front and bottom part
• Facial Bones
  • Irregular structures in the face

Long Bones

• Arms
  • Humerus, ulna (midline), radius (thumb side)
  • Metacarpals and phalanges in hands (considered long because longer than wide)
• Legs
  • Femur, tibia (larger), fibula (lateral side)
  • Metatarsals and phalanges in feet
• Clavicle
  • Part of appendicular skeleton, longer than it is wide

Short Bones

• Tarsals
  • Small bones in the foot, part of the ankle
• Carpals
  • Bones in the wrist
• Patella
  • Also known as a sesamoid bone due to its sesame seed shape, referred to as a short bone

Flat Bones

• Ribs
  • Curved and flat, part of the thoracic cavity
• Skull
  • Curved and flat bones at the top
• Scapula
  • Flat and curved
• Sternum
  • Flat bone in the middle of the thoracic cavity

Key Points

• Irregular bones do not fit other classifications due to unusual shapes.
• Long bones are typically found in the arms and legs.
• Short bones are small and often cube-shaped, like the tarsals and carpals.
• Flat bones are typically thin and curved.
• Understanding classification helps identify each bone's characteristics and functions.

Conclusion

• Each bone in the body can be classified as either long, short, flat, or irregular, aiding in their identification and study.