A 58-year-old accountant has had six months of numbness in the right little finger and clumsiness doing up buttons. He rests his elbows on his desk all day and cycles to work on dropped handlebars. The first dorsal interosseous muscle is wasted. Tapping just behind the medial epicondyle reproduces tingling in the little finger. When he pinches a sheet of paper between thumb and index finger, the thumb bends at its end joint.
Which one of the following combinations of finger posture and sensation over the dorsum of the medial hand would you expect in this man?