The palm of the hand HAS to be the worst source of blood...right?

[Ionathus]

I feel like I see this in TV shows and movies all the time. A character needs a few drops of blood for whatever reason, so they cut themselves on the hand or on the finger. A short list that comes to mind now:

• In National Treasure, the main character cuts his thumb to spread some blood on a cylindrical "stamp" and get the next clue
• In Pirates of the Caribbean 1, giving blood to the cursed chest of gold always comes from the palm of the hand. The pirates cut Elizabeth's palm against her will, and then later, Jack and Will both willingly cut their palms for the same reason.
• In Damsel (the new Millie Bobby Brown film), two characters need to be "joined by blood", which they accomplish by cutting their palms and holding hands to let the blood mingle (gross).

(I'm certain there are others -- I feel like I see this trope A LOT -- but those are the ones that come to mind right this moment. Weirdly, Jerry Bruckheimer directed two of them. Connection...?)

Anyway, to my point: that can't be the best way to go about that, right? Hand wounds feel like the absolute worst spot just in day-to-day life, and I don't even live in a swashbuckling or adventure story. Wouldn't it make more sense to make a small cut on the back of your forearm, or your bicep, or somewhere that doesn't require a ton of manual dexterity and can be easily bandaged? Obviously you wouldn't want to, like, open a major artery since that would be a different kind of problem. But I feel like there have to be better options than "the part of my skin that I use to touch every external object".

Is there something anatomically "perfect" about the hand, where you get a reliable blood supply but there's no danger of bleeding out? Do the wounds heal more quickly or reliably? I know finger-pricks have a long tradition of consistent blood testing, so maybe there's something else going on here that I don't know about.

And of course, I understand that cutting the palm of your hand is really visually interesting to represent a token blood sacrifice. I totally get why filmmakers choose it, for the symbolic value and the "ouch" factor you get from audiences imagining cutting their own hands. But come on! There's gotta be a more practical spot to get a teaspoon of blood from!

[Mx.Silver]

I feel like I see this in TV shows and movies all the time. A character needs a few drops of blood for whatever reason, so they cut themselves on the hand or on the finger. A short list that comes to mind now:

• In National Treasure, the main character cuts his thumb to spread some blood on a cylindrical "stamp" and get the next clue
• In Pirates of the Caribbean 1, giving blood to the cursed chest of gold always comes from the palm of the hand. The pirates cut Elizabeth's palm against her will, and then later, Jack and Will both willingly cut their palms for the same reason.
• In Damsel (the new Millie Bobby Brown film), two characters need to be "joined by blood", which they accomplish by cutting their palms and holding hands to let the blood mingle (gross).

(I'm certain there are others -- I feel like I see this trope A LOT -- but those are the ones that come to mind right this moment. Weirdly, Jerry Bruckheimer directed two of them. Connection...?)

Anyway, to my point: that can't be the best way to go about that, right? Hand wounds feel like the absolute worst spot just in day-to-day life, and I don't even live in a swashbuckling or adventure story. Wouldn't it make more sense to make a small cut on the back of your forearm, or your bicep, or somewhere that doesn't require a ton of manual dexterity and can be easily bandaged? Obviously you wouldn't want to, like, open a major artery since that would be a different kind of problem. But I feel like there have to be better options than "the part of my skin that I use to touch every external object". Is there something anatomically "perfect" about the hand, where you get a reliable blood supply but there's no danger of bleeding out? Do the wounds heal more quickly or reliably? I know finger-pricks have a long tradition of consistent blood testing, so maybe there's something else going on here that I don't know about.

If you're just trying to get blood then yes, there would be better options. But that's the thing: none of these examples are "just" getting blood, they're applying it, and in that case the hand is the most practical option because it's what you use to touch external objects. They're one of the least likely places to be clothed (making access easier) and, while long-term healing is annoying, in terms of wound care they're easy to inspect, apply pressure to, and are easier to self-bind than arm cuts.
It's sort of a short-term practicality vs long-term inconvenience trade-off.

With regards to blood oaths/blood brotherhood (such as the last example) the fact that hand contact is also a bonding gesture to start with could potentially be a factor too. The long-term inconvenience of hand wounds might also lend some symbolic weight to it, but that would probably depend a lot on which cultural tradition you're looking at.

And of course, I understand that cutting the palm of your hand is really visually interesting to represent a token blood sacrifice. I totally get why filmmakers choose it, for the symbolic value and the "ouch" factor you get from audiences imagining cutting their own hands. But come on! There's gotta be a more practical spot to get a teaspoon of blood from!

Palm cuts are also quite easy to stage, since it's fairly trivial to hide a small squib/blood packet in your hand and disguise it being opened from the audience. Which is partly why they're a bit over-represented in film and theatre.

[Mordar]

Don't forget - there is a reason diabetic blood testing has used finger pricks for decades. Reliable, easily managed, easily cleaned, and while a bit of an annoyance, not debilitating.

For arcane rituals and such, maybe the palm gives more control...or it is simply supposed to suck more to power the magic (makes it more of a sacrifice than using a few vacutainers to draw from the antecubital with no muss, fuss and just a cottonball and a bit of coban).

- M

[Ionathus]

All good points, thank you both for your responses! The control and ease of wound care are both good points (more so for fingertips than the palm of your hand -- palm wounds are just awful to bandage in my experience).

I guess I'm still hung up on two nitpicky practical things: the risk of infection, and the annoyance of bumping your cut on stuff. Major knee or arm scrapes are annoying, but nothing's worse to me than a finger cut brushing against the edge of my pocket or a pen I'm trying to hold.

The first one is unheard of in fiction (despite most of these settings being pre- or non-antibiotics ) and the second is probably a net positive in fiction as Mx. Silver said, since "I'm willing to casually inconvenience myself with this wound" usually makes someone more of a badass and never presents any of the logistics wrinkles that real life would encounter. So I understand why they do it, for the most part, even if it still doesn't feel like the most practical option.

[halfeye]

There was a time when I was having a lot of small blood tests, they typically took from the inside of the elbow, the back of my hands were a second choice, but they were looking for veins, not arteries.

[Quizatzhaderac]

I suspect that there's something with stagecraft here.

Like, maybe in a live theater performance you could pre-bloody the palm of your hand and only show it after "cutting" it.

When film becomes a thing, nobody bothers thinking up a clever editing or angle trick, because we all know this perfectly good palm trick from theater.

[Murk]

Is there something anatomically "perfect" about the hand, where you get a reliable blood supply but there's no danger of bleeding out? Do the wounds heal more quickly or reliably?

This got me thinking what the perfect location would be, and my money is on the inside of the nose.

- Very easy to make it bleed, I can do it with my own fingernail!
- Bleeds a lot and easy to keep the wound open, so reliable supply
- but also easy to stop the bleeding when you want, so not very dangerous.
- Easy to aim.
- I've never heard of a nosebleed getting infected, it doesn't even need to get bandaged.
- Not on the outside of your skin so it won't touch anything while it heals

And as a cinematic bonus:
- Easy to hide fake blood capsules on stage.
- Very symbolic: close to the brain!
- Properly gross.

[Batcathat]

This got me thinking what the perfect location would be, and my money is on the inside of the nose.

- Very easy to make it bleed, I can do it with my own fingernail!
- Bleeds a lot and easy to keep the wound open, so reliable supply
- but also easy to stop the bleeding when you want, so not very dangerous.
- Easy to aim.
- I've never heard of a nosebleed getting infected, it doesn't even need to get bandaged.
- Not on the outside of your skin so it won't touch anything while it heals

And as a cinematic bonus:
- Easy to hide fake blood capsules on stage.
- Very symbolic: close to the brain!
- Properly gross.

I think one potential downside (though that might apply to some of the alternatives, too) is that some of this depends on the individual. When I was a kid, my nose started bleeding quite frequently for little to no reason, but it bled so little I usually didn't even had to do anything but lean my head back a little. Meanwhile, my sister's nose didn't start bleeding nearly as often but when it did, it was basically like someone had turned on a tap of blood, I remember her even having to sit over the sink a couple of times since it just bled through paper or wool (and she eventually had to cauterize her blood vessels or something along those lines). I don't know how representative either of us is, but still.

[Maat Mons]

I remember my dad telling me about a guy he knew in high school who suffered an injury to his palm. Apparently the wound went deep enough to cut a ligament or tendon or something. The hand was never really the same.

[Ionathus]

I donated blood yesterday, which involved a finger prick to test and then an arm vein blood draw, and it reminded me of this conversation.

Honestly, the finger prick wasn't nearly as bad as I remembered. I recalled it getting in the way a lot more, but finger prick was actually more convenient than I remembered. Makes sense why that was the convention for testing blood sugar for ages and ages...That doesn't mean I'm going to forgive Nicholas Cage for jabbing a knife directly into the pad of his thumb in National Treasure of course

I remember my dad telling me about a guy he knew in high school who suffered an injury to his palm. Apparently the wound went deep enough to cut a ligament or tendon or something. The hand was never really the same.

This is always my fear! I just wince whenever they do it in fiction -- Pirates of the Caribbean 1 in particular, the move that Jack does to coat the cursed gold with his blood is really cool but holy hell, does it look painful and dangerous.

[Bohandas]

For arcaane rituals and such, maybe the palm gives more control...or it is simply supposed to suck more to power the magic

Cutting the palm of your hand changes your destiny and it's a lot easier than moving the stars around

[Eldan]

This got me thinking what the perfect location would be, and my money is on the inside of the nose.

- Very easy to make it bleed, I can do it with my own fingernail!
- Bleeds a lot and easy to keep the wound open, so reliable supply
- but also easy to stop the bleeding when you want, so not very dangerous.
- Easy to aim.
- I've never heard of a nosebleed getting infected, it doesn't even need to get bandaged.
- Not on the outside of your skin so it won't touch anything while it heals

And as a cinematic bonus:
- Easy to hide fake blood capsules on stage.
- Very symbolic: close to the brain!
- Properly gross.

On the other hand, given that we're often talking medieval times: an infection in your hand is easy to treat by cleaning and you have the option of amputation if you really need to. An infection in your face just kills you, very quickly.

[Ionathus]

On the other hand, given that we're often talking medieval times: an infection in your hand is easy to treat by cleaning and you have the option of amputation if you really need to. An infection in your face just kills you, very quickly.

Counterpoint: you're far less likely to stick your nose in something dirty than your hand.

Also, you can always cut off your nose to spite save your face

[Eldan]

You can cut off your nose, but it's actually a real problem that infections around the nose and teeth can spread to the brain extremely quickly because there's direct connections. It's why a tooth abcess can kill you if you don't treat it early and indiscriminately.

[halfeye]

There are tales of people pricking their fingers and dying of it. Amputation solves gangrene, but there are other infections that are quicker.