Digital Anatomy Companion Site

The Hand

msonnenfeld

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Learning Objectives

By the end of this section, you will be able to:

  • Identify the bones of the hand: carpals, metacarpals, and phalanges
  • Describe the general arrangement of these bones and their functional roles
  • Locate these bones on anatomical figures and interactive models

Bones of the Hand

There are 27 bones in the hand:

  1. Phalanges – Four fingers have three phalanges each (proximal, middle, distal), while the thumb has two.

View the rotating gif of the phalanges of the left hand highlighted in red. This image is rendered using Blender Blender with polygon data from BodyParts3D by DBCLS.

https://commons.wikimedia.org/wiki/File:
Phalanges_of_the_hand_(left_hand_-_animation01.gif) (CC BY 2.1 JP)

2. Metacarpals – Five bones forming the palm, numbered 1–5 starting from the thumb side.

View the rotating gif of the metacarpals of the left hand highlighted in red. This image is rendered using Blender Blender with polygon data from BodyParts3D by DBCLS.

https://commons.wikimedia.org/wiki/File:
Phalanges_of_the_hand_(left_hand_-_animation01.gif)(CC BY 2.1 JP)

3. Carpals – Eight wrist bones arranged in two rows of four. Two bones of the proximal row articulate with the radius. (You do not need to memorize individual names.)

View the rotating gif of the carpals of the left hand highlighted in red. This image is rendered using Blender Blender with polygon data from BodyParts3D by DBCLS.

https://commons.wikimedia.org/wiki/File:Carpus_(left_hand)_-_animation01.gif (CC BY 2.1 JP)

Study Hint: “Clap your carpals and tap your tarsals”

Examine the labeled figure below. Use it to identify the carpals, metacarpals, and phalanges. Pay attention to their arrangement and numbering.

Watch this AnatomyZone video for a guided overview of the hand and wrist bones. Click here to watch the video.

Interact with a 3D model of the hand and wrist. Rotate, zoom, and click on bones to test your knowledge. Click here to explore the hand and wrist in 3D!

Note; you do not have to know individual specific bone names.

Answer:
The thumb has only two phalanges because it needs greater mobility for opposition and precision grip. Reducing one phalanx shortens the thumb and allows it to rotate and touch the tips of other fingers, which is essential for grasping and manipulating objects.

Test Your Knowledge

Revisit the Innerbody website (Upper Limb: Bony Landmarks) before trying the Beat the Clock exercise below. Click 3D rotate and zoom to begin your journey. Try identifying hand bones before clicking on them —can you identify each category based on what you’ve learned already?