(pahl'măr met'ă-kahr'păl ahr'tĕr-ē) One of three arteries springing from the deep palmar arch and running in the three medial interosseous metacarpal spaces; they anastomose with the common palmar and, through perforating branches, with the dorsal metacarpal arteries. Synonym(s): arteria metacarpalis palmaris, palmar interosseous artery.