Appendicular skeleton

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Appendicular skeleton
Human appendicular skeleton
Details
Identifiers
Latinskeleton appendiculare
TA98A02.0.00.010
TA2359
FMA71222
Anatomical terminology

The appendicular skeleton is the portion of the

caecillians), the appendicular skeleton and the associated skeletal muscles are the predominant locomotive
structures.

There are 126

feet.[1] These bones are homologous to those in the forelimbs and hindlimbs of all other tetrapods
.

Etymology

The

PIE root *(s)pen- meaning"to draw, stretch, spin").[3]

The organization of the appendicular system

Of the 206 bones in the human skeleton, the appendicular skeleton comprises 126. Functionally, it is involved in locomotion (lower limbs) of the axial skeleton and manipulation of objects in the environment (upper limbs).

The appendicular skeleton forms during development from cartilage, by the process of endochondral ossification.

The appendicular skeleton is divided into six major regions:

  • Shoulder girdle (4 bones) - Left and right clavicle (2) and scapula (2).
  • Arms and forearms (6 bones) - Left and right humerus (2) (arm), ulna (2) and radius (2) (forearm).
  • Hands (54 bones) - Left and right
    distal phalanges
    (10).
  • Pelvis
    (2 bones) - left hip bone and right hip bone (2).
  • Thighs and legs (8 bones) - Left and right femur (2) (thigh), patella (2) (knee), tibia (2) and fibula (2) (leg).
  • Feet and ankles (52 bones) - Left and right
    distal phalanges
    (10).

Through

sutural bones in the skull, cervical ribs, lumbar ribs, and a sixth lumbar vertebrae
. Some occurrences are rarer than others.

The appendicular skeleton of 126 bones and the axial skeleton of 80 bones together form the complete skeleton of 206 bones in the human body. Unlike the axial skeleton, the appendicular skeleton is unfused. This allows for a much greater range of motion.

See also

  • Legs

References

  1. ^ Skeleton Encyclopædia Britannica. Updated 24 August 2014.
  2. ^ "Appendicular (adj.)". Online Etymology Dictionary. Retrieved 2024-02-06.
  3. ^ "Appendix (n.)". Online Etymology Dictionary. Retrieved 2024-02-06.