Deep fascial spaces of the hand

The palm has three potential closed spaces with well-defined anatomical borders; the thenar, the midpalmar, and the hypothenar space. These spaces are deep to the flexor tendons but superficial to the interosseous muscles. Infections in these spaces occur following a penetrating injury in most cases and occasionally as an extension from a subcutaneous abscess or adjacent pyogenic flexor tenosynovitis.
(A) The deep spaces of the palmar aspect of the hand.
(B) The extent of the deep palmar spaces of the hand.