Black Jack (TV) - episode 13 - 30 Jan, 2005

Ichinoseki is a local star gymnast. He loses an arm to gangrene, and Black Jack replaces it with a metal pincer. Ichinoseki becomes depressed, but his arm talks him into playing competitive shogi. He wins the championship, and the arm turns out to be voiced via transistor by his long-suffering friend Toshie. (Source: Wikipedia)