Ulnar Claw Hand (Claw Hand): this is because of a lesion on the ulnar nerve. The MCP joints are hyperextended to the ring and small fingers mainly because of the loss of the 3rd and fourth lumbrical muscles because of a lesion on the deep branch with the ulnar nerve. Dr https://www.theorthopaedicandpainpractice.com/what-are-the-different-bones-found-in-my-hand/