Human fingers do not have any muscles inside them.

There are 34 muscles that control your hand, but none are in the fingers. Your fingers are made of bones called phalanges, joints, and ligaments. Keeping the muscles in the arm allows fingers to stay thin and move easily for small tasks.The muscles that help you make a fist are in your forearm. These are called the flexor digitorum profundus and the flexor digitorum superficialis. They turn into long cords called tendons that travel through your wrist. When these muscles tighten, they pull the tendons to bend your fingers.Another set of muscles on the other side of your arm helps you straighten your fingers. These are called extensors. Small rings of tissue called pulleys hold the tendons close to the bone. These pulleys prevent the tendons from popping out when you bend your hand.The thumb is the only part with its own small muscles at the base. This helps the thumb move in many directions and touch the other fingers. However, the thumb still gets most of its power from the forearm. This is why your grip strength depends on how strong your arm muscles are.