Hands

Last revised by David Carroll on 4 Dec 2022

The hand is part of the upper limb below the forearm and wrist. In the supinated anatomical position, the palm is facing anteriorly and the dorsum posteriorly.

The bones of the hand are:

As the thumb is structurally different to the other digits of the hand, with different movements and musculature, there is debate as to whether the thumb is considered a finger 2. It can therefore confusing to refer to the fingers by number - is the "first finger" the thumb or the first of the four other digits? For this reason it is advisable to refer to the digits by names given to them rather than by number. From the radial to the ulnar aspect of the hand, they are named as follows:

  • thumb

  • index finger

  • middle finger or long finger

  • ring finger

  • little finger

In the standard anatomical position, the hand is flat and supinated with the fingers spread. This positions the thumb at the lateral aspect of the hand and the little finger at the medial aspect of the hand. It is often easier to use radial and ulnar to refer to the lateral and medial aspects of structures in the hand, as these may be more intuitive without having to remember the anatomical position. 

Hand movement is complex and occurs across many joints, including those involved in wrist flexion.

Muscles of the hand can be divided into:

Fascial layers subdivide the underlying musculature into functional compartments; clinical relevance becomes manifest with pathologic increases in pressure resulting in ischemia and/or necrosis to the structures within the myofascial confines such as muscle and peripheral nerves.

The compartments are typically identified as the following 3:

  • thenar compartment

    • contains abductor pollicis brevis, opponens pollicis, flexor pollicis brevis, ulnar nerve branches

  • hypothenar compartment

    • opponens digiti minimi, flexor digiti minimi, abductor digiti minimi

  • adductor pollicis compartment

  • interossei compartments

    • encompasses 3 palmar and 4 dorsal compartments

    • no musculature, contains ulnar nerve branches

  • central or mid-palmar compartment

    • anatomically continuous with the carpal tunnel

    • contains the second through fourth lumbrical muscles

ADVERTISEMENT: Supporters see fewer/no ads

Cases and figures

  • Figure 1: flexor insertions at the hand and wrist
    Drag here to reorder.
  • Figure 1: extensor insertions at the hand and wrist
    Drag here to reorder.
  • Figure 2a: muscle attachments (Gray's illustration)
    Drag here to reorder.
  • Figure 2b: muscle attachments (Gray's illustration)
    Drag here to reorder.
  • Figure 3a: normal anatomy (frontal)
    Drag here to reorder.
  • Figure 3b: normal anatomy (oblique)
    Drag here to reorder.