For our homework in life drawing, I have to draw hands and creat ana animation.

I like to understand the underlying structure of hands over just blindly drawing a shape without an understanding of its underlying structure. And so I started by looking at the bones of the hand.

hand

The hand is comprised of three parts:

  1. Carpus
  2. Metacarpus
  3. Phalanges

Carpal Bones

These are arranged below the forearm int wo rows. Starting from the thumb side, the following bones are found in the upper row:

  1. Scaphoid
  2. Lunate
  3. Triquetral
  4. Pisiform

The lower row are:

  1. Trapezium
  2. Trapezoid
  3. Capitate
  4. Hamate

The largest bone of the wrist is the Capitate. The hamate bone has a hook-like pricess projecting on its palmar aspect. The bones of the upper row form, by their peculiar articulations, a concavity resembling an excavated joint surface which surrounds rhe capitate.

Metacarpal Bones

There are five metacarpal bones. They become gradually larger as they get cloer to the thumb and form a united mass. The thumb’s metacarpal bone differs from the metacarpal bones in the fingers in regard to form and poisiton, it is shorter and thicker than the others.

Phalanges

Each finger consists of three phalanges, whilst the thumb only consists of two. They are unqual in length.

Sesamoid Bones

Two small bones opposite the head of the metacarpus of the thumb. There are sometimes similar bones opposite the heads of the other metacarpal bones, particularly the second and the fifth.

The Joints and Movements of the Hand

The movements of the hand are various. It can be flexed, hyoerextended, adducted and rotated. The function of the carpo-metacarpal joints is not unifrm, as the thumb moves differently from the fingers. The joints of the fingers are rigid, whilst the thumb has a saddle-like articular surface, giving it more mobility.

Joints and Movements of the Fingers

The articular surfaces of the metacapro-phalangeal joints are, in the three-phalangeal fingers, sphereical and cylindrical, allowing these joints to flex, extend, adduct, abduct and even rotate. The articular surfaces of the two interphalangeal joints are cylindrical; thus they represent hinge-joints.Between the two phalanges of the thumb there is a hinge-joint, allowing movements in one plane only.

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