Ulnar Claw Hand (Claw Hand): this is due to a lesion in the ulnar nerve. The MCP joints are hyperextended to the ring and tiny fingers a result of the loss of the third and fourth lumbrical muscles as a result of a lesion with the deep branch of the ulnar https://www.theorthopaedicandpainpractice.com/what-are-the-different-bones-found-in-my-hand/