When I first saw the show as a kid I didn't get the joke at the end of the theme song, so for a while I thought Dr. Claw was just a hand stuck to a chair.
There is a fan theory along those lines: once upon a time a police inspector was horribly injured in the line of duty, and his niece created a robot replica of him. And the original ... ? All that's left is an arm, stuck to a chair. An arm who hates the robot replica, but still has enough feelings for his niece to never put her in harm's way.