Upper Arm

Ape Hand is just flattening of the thenar eminence. Look at an ape's hand if you get the chance, they don't have a buldge on the palm proximal to the thumb. It comes from median nerve palsy, like carpal tunnel.


Hand of benediction looks like the pope blessing someone. I bet you can google an image of it. The ring and little fingers are flexed (4th and 5th digits), while th e others are extended. Its an ulnar nerve palsy (a lot one, beyond mid forearm).

Saturday Night Palsy is a high radial nerve lesion, like from having your arm propped up on a movie chair or bar or such. Or crutches. So lack of extension, wrist drop, etc.

Just google the terms and you can get much more info.

Janders said:

Ape Hand is just flattening of the thenar eminence. Look at an ape's hand if you get the chance, they don't have a buldge on the palm proximal to the thumb. It comes from median nerve palsy, like carpal tunnel.


Hand of benediction looks like the pope blessing someone. I bet you can google an image of it. The ring and little fingers are flexed (4th and 5th digits), while th e others are extended. Its an ulnar nerve palsy (a lot one, beyond mid forearm).

Saturday Night Palsy is a high radial nerve lesion, like from having your arm propped up on a movie chair or bar or such. Or crutches. So lack of extension, wrist drop, etc.

Just google the terms and you can get much more info.

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Just a correction, the hand of papal benidiction is a median nerve paly, that is why you are able to flex the 4th and 5th digits (supplied by ulnar nerve) and fingers 2 and 3 are extended (unopposed action of radial nerve). Also the median nerve supplie the OAbF muscles but not the adductor. So the thumb would be adducted. Sorry for the drawn out explanation.

hamedn said:

Just a correction, the hand of papal benidiction is a median nerve paly, that is why you are able to flex the 4th and 5th digits (supplied by ulnar nerve) and fingers 2 and 3 are extended (unopposed action of radial nerve). Also the median nerve supplie the OAbF muscles but not the adductor. So the thumb would be adducted. Sorry for the drawn out explanation.

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Seems we are both right. On further google-review, I found official-looking medical websites blaming Hand of Benedication on both ulnar (via the fact that 4th & 5th fingers are hyperextended at MP joints by long extensors but flexed at interphalangeal joints) and median (as you said, can't flex 2 or 3) nerve lesions. I am not sure if both or right, or neither, or what. Perhaps someone else can add their two cents.

Can someone post a pic of the dif between the ulnar claw and the sign of benediction, they seem very similar from the descriptions I've read

me454555 said:

Can someone post a pic of the dif between the ulnar claw and the sign of benediction, they seem very similar from the descriptions I've read

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I beleive in one (claw hand) your hand is stuck like that), in the other (papal benidiction) it only has that appearance when the patient is asked to make a fist. Someone let me know if this is correct

I was just going over this with a friend who is much smarter than me. We both used Moore's anatomy text for school.

Hand of Benediction = Median nerve palsy. It's important to note that the median nerve has to be lesioned more proximally than at the carpal tunnel, more like up at the elbow. Otherwise you've got an unopposable thumb (like an ape).

Claw hand = Ulnar palsy. This injury is more, however, than simply a failure of the 4th and 5th digits to flex. Since the ulnar nerve innervates the interossei, the actions of the lumbricals and finger extensors become unopposed. The MCP joint is flat, pulled back into extension.

This stuff was confusing to learn, not least because of conflicting terms and sources. Of course, such confusion will have been sorted out by the authors of STEP 1, I'm sure . . .