Useless Spleen

"The spleen! Why is it always the spleen?!"

—Numerous victims of Shirt Guy Dom from Megatokyo

As far as human organs go, there is the common idea that no one knows exactly what the spleen does.

Therefore, a common sight in fiction is that either the spleen is a completely useless part of the human body, or it serves some sort of encumbering function. Often Played for Laughs, especially with the implication that damage or loss of the spleen is trivial and harmless.

Because of the Inherently Funny Words effect, spleens are often mentioned for a punchline or joke. This mostly happens in an Arson, Murder, and Jaywalking manner, with the spleen as the jaywalking.

Along with the fact that it's seen as useless, the spleen is often portrayed as a convenient place to get hurt/injured in a fight, possibly because it is somehow considered funny.

In fact, the spleen plays a very important role in the lymphatic and immune systems. It is easily ruptured by blunt or piercing impact and is very difficult to repair (doctors say that it has the natural consistency of a blood-soaked sponge). If damaged, it must be removed surgically or the person in question is likely to bleed to death; once removed, the person has to take care to avoid bacterial and protozoan infections (to which they become more susceptible). A fairly comprehensive treatment of the subject is covered in a blog entry by Dr. Scott.

Compare We Will Not Have Appendixes in the Future. Not to be confused with the useless Spleen.

Examples of Useless Spleen include:

Card Games

In Mark Gottlieb's Magic: The Gathering article "Combos: Future Sight Edition", he takes a spleen-piercing bullet to the spleen.

Comics

Tim Drake loses his spleen to a sword-strike in Red Robin #4.

Commercials

Inverted in a recent ad for a Batman video game, in which Harley Quinn has a voiceover similar to theme park's "keep hands in car at all times" announcements. Harley denies liability for injuries to a series of body parts, including "spleen or other vital organs". The spleen may not be useless, but it's not a vital organ either: you can survive without one, else removing a damaged spleen would not be an option.

Comedy

In a song by German comedian Otto Waalkes, the procedures in the human body are humorously described. A man is sitting in a pub and being insulted, and the spleen is terminally bored, asks for something to do and tries to suggest actions, but the brain tells the spleen to shut up.

Literature

In the Spider-Man novel "The Venom Factor" Venom states that when he finds whoever is responsible for the murders (that Venom is being wrongly accused of) he will eat his spleen. Spider-Man comments that this is an odd choice of organ to target and that Venom likely doesn't even know where someone's spleen is.
In Mockingjay, Katniss is shot. Despite a bullet-proof costume, she suffers bruised ribs and a ruptured spleen.
In Tom Clancy's Patriot Games, Jack Ryan's wife and daughter get into a messy car crash thanks to being shot at by terrorists. His wife turns out reasonably okay, but his daughter Sally barely survives, and the surgeon mentions that her spleen was ruptured and had to be removed.
The Star Wars Expanded Universe, of all things, contains a notable aversion of this trope. During a dangerous, practically suicidal mission, Anakin Solo sustains a huge wound to his spleen while protecting a loved one. He bleeds to death. And, despite his huge fanbase and his general importance in-universe, they ain't bringin' 'im back.
Averted in the Stardoc series—or at least for the Jorenian race, for whom it's a vital organ.
Subverted: Rudyard Kipling's poem "The Ballad of Boh Da Thone" tells how the titular bandit prince died. It's played for laughs — the cause of death was an obese bureaucrat accidentally falling atop him — but there's specific mention that the Boh's spleen, enlarged by illness, made him even more vulnerable than otherwise to the shock of all that weight (20 stone, i.e., 280 pounds/127 kilograms) abruptly landing on him.

And twenty stone from a height discharged
Are bad for a Boh with a spleen enlarged.

Live Action Television

Averted on a sketch on All That, a character has forgotten to bring something for show and tell. He takes his friend out in the hall and when they return, he has removed his friend's spleen and is ready to present it for show and tell while his friend stands next to him, doubled over in pain. He ends his presentation with something along the lines of "Humans are incapable of surviving without their spleen," at which point his friend gets worried and then collapses.

Music

There's the line "My spleen just doesn't matter" in Weird Al's song "Pancreas."
In a parody of "Ain't Got No", a song from Hair (theatre), a line is "Got my spleen (whyever)".

Newspaper Comics

A Far Side cartoon with "Having explored the heart of the jungle, the intrepid explorers now entered the spleen". Another has Edgar Allan Poe with list of crossed-out titles, such as The Telltalle Brain and The Telltale Spleen.
A common punchline in Brewster Rockit involves Winky being attacked by an alien and screaming "Ah! My spleen!"
In an Over the Hedge strip where Verne gets in a sledding accident his spleen is one of several organs scattered across the landscape. Another time when RJ is trying to convince him to get past a Mayan warrior-priest guarding a fridge he tells him that guy is more likely to grab a kidney or spleen than heart, and you can live without a kidney or spleen.

Tabletop Games

Averted in Promethean: The Created; the spleen is vital to Prometheans, as in the distribution of humours, it is the origin of blood. (In reality, it breaks down old blood cells, but alchemy was never exactly on top of biology.) Growing an extra spleen via Lovecraftian Superpowers has multiple benefits.

Video Games

In Kingdom of Loathing, the spleen is stated to be completely useless but still cumbersome, because it limits the number of stat-increasing items you can consume per day.
- Also, a concert promoter is threatened by managers with "having his spleen removed through his nostrils" if he cannot make enough people attend a concert.
There is a quest in Fallout 2 which requires you to retrieve someone's spleen which was surgically removed while they were unconcious; failing to return it results in them dying after an allotted time.
Rikku in Final Fantasy X-2 has the in-battle quote: "Imma kick you in the spleen!", to which Paine replies "...Spleen?"
Jormungandling's spleen is a relatively dangerous enemy in Wandering Hamster which taunts you througout his belly. Killing it doesn't seem to affect the snake in any way.
There are several types of enemies in No More Heroes who yell "MY SPLEEN!" upon getting killed. Considering that they usually get chopped in half, you would think that would be the least of their concerns.
Chaos Cultists in Dawn of War exist to die in large numbers. One of their reactions to being killed is "Augh! My SPLEEN!."

Web Comics

Played with in Order of the Stick, when Elan is badly wounded and he almost loses something which presumably is his spleen, he asks: "How important is one of these?"
- Said wounds were due to being Impaled with Extreme Prejudice, after which he states, "Look, I found all these free swords. They were in my spleen."
"Has anyone seen my spleen?" is a common phrase in the aftermath of combat in Dork Tower.
Shirt Guy Dom from some Megatokyo filler strips certainly qualifies -- there's a reason he has a spear named Spleen Slayer.
The spleen is the most-mentioned organ in Chopping Block. Butch admits he has no idea what it does, but he claims it has "a certain je ne sais quois."

Web Original

The first incarnation of GRIT had a villainous character named P-Word who often threatened to rip out people's spleens.

Western Animation

In The Fairly OddParents, in an attempt to beat Timmy up while Timmy blocks his attempts with his newly-gotten attendance award, Francis can be heard shouting "Ow, my hand! Ow, my other hand! Ow, my head! Ow, my spleen!" as he continues to take swings.
- In another episode Timmy's Dad decides to get a new job on the internet Cosmo and Wanda pose as interactive characters on the website, he pokes Cosmo with the arrow and he says "Ow, my spleen!".
Invader Zim had Dib's spleen getting damaged during a Fantastic Voyage.
Mucha Lucha has The Flea thinking his spleen as this, and lies about having hurt his spleen whenever he wants to get out of something. Then an evil doctor tries to steal it to create a bio-robot, but his spleen literally exits his body and beats up the robot in a wrestling match. And the Flea's other organs also join in the fight. Then returns to his body. Moral of the story is that the spleen is not a useless organ.
- Subverted in a final scene showing the Flea's spleen return to his "home", he does nothing but watch TV.
In an episode of Hey Arnold!, Eugene has his tonsils removed in a hospital mixup. He says it's alright, he doesn't need them anyway...but wishes they had left his spleen. Then he flashes the scar.
In an episode of Beavis and Butthead, the duo try to get money by suing people for injuries they supposedly obtained from people, near the end Beavis is hit by Tom Anderson's car, he isn't seriously injured but he pretends to be he shouts "Ow, my spleen!" but he grabs at his crotch when he says this probably not knowing what one is.
Averted in Ozzy and Drix, where Ozzy dispatches one villain by luring him to the spleen and describing its functions. Said spleen is effectively a Turbine Blender.

Real Life

Averted every time a patient with a possible infection has their left side palpated by a doctor, as feeling that the spleen is enlarged can be a useful first indicator of ailments such as mononucleosis.
- Though you can survive without one, with some medication.