What are the muscles actions when fingers are extended and splayed?

When fingers are extended and splayed, the primary muscles involved are the extensor digitorum, which extends the fingers at the metacarpophalangeal joints, and the intrinsic muscles of the hand, particularly the dorsal interossei, which help to abduct the fingers. The extensor tendons facilitate extension, while the interossei muscles provide the necessary spread between the fingers. Additionally, the extensor indicis and extensor digiti minimi can assist in extending the index and little fingers, respectively. Overall, this action is coordinated to allow for a wide range of finger movement and function.