Muteness.

My favorite character in my story can't speak. He can make a few growly sounding noises, but that's it. At first I just described him as having scars on his throat that would kind of serve as a 'hey, I can't speak' sign for other people. Then I realized that I couldn't think of an accident that would have such a dramatic effect on his voice without killing him.

There is no surgery in the time period this is set in, so he's prettty much stuck like this. But how did he get that way? I was juggling the idea of some kind of disease, but then I had an idea. People lose their voices from screaming for a prolonged period of time. How much screaming would it take to lose it permantly? Is that even possible? I'm kind of hoping it is, because it would fit in with my story perfectly. What do you think?

Well, I know people can be born mute. It's also often associated with deafness, as deaf people will sometimes choose not to speak since they cannot hear themselves or others (it's kind of hard to form words and learn how to speak when you don't even know what sound is like exactly). I think not having enough iodine in one's diet as a youngster can lead to one becoming mute, because it somehow deters the formation of the thyroid and damages the auditory system. Injury-wise, I know brain injury, drugs, and strokes can also lead to mutenes.

Botched throat surgery. Like a tonsellectomy or something mainstream that would take a lot to mess up.

I don't think it's believable that screaming, even extremely loud and for an extremely long time, could cause the voice to permanently disappear. For a short time, sure. Voice is forever damaged, ie croaky or husky, sure. But not to the point where he can never speak again.

I think your best option is a wound to the throat, but an infection/disease of some kind might also work.

Have him damage his voice by screaming and then live without speaking for years. In addition to the injury he would probably lose his voice due to disuse and/or trauma.

I know a fair bit about screaming and losing one's voice, having been in metal bands all my life.

What we call vocal cords are more accurately described as vocal folds. They are flaps of tissue, one on each side of your throat. When you vocalise they expand out and meet in the middle - think of it like a pair of automatic doors opening and closing. This modulates the airflow and creates noise. Syllables - shaping the noise into words - do NOT come from the vocal folds, and instead come from the tongue and soft palate reshaping the noise.

To make higher noises they move more frequently and faster. It takes practice to move them faster (like using any muscle), which is why some people can sing higher than others. To make lower noises they have to move slowly. The tone of someone's voice is essentially how quickly their vocal folds move together "normally".

To make louder noises they more further, retracting back further and coming back in to still meet in the middle, which is why your voice might "break" when you shout if the folds don't fully meet. If you don't shout "correctly" then the folds will bang together and get bruised, which means you can't move them as fast or as far, which is why you lose your voice after shouting. To whisper they stay in the middle and sorta rub together, which is a REALLY bad thing if you have bruised your vocal folds from shouting. So if you lose your voice, speak normally and don't whisper.

So when you scream poorly and bang those folds together, they can get so bruised that they stop working. But it's only a bruise. If you get a black eye you may not be able to open your eye for a couple of days, then it will get better. Same with your voice - it will heal. So it is highly unlikely that screaming could render you permanently mute. You may have heard of polyps on the vocal folds, which are like scars from repeated abuse and healing. These will prevent the folds from vibrating as they are meant to, screwing your singing voice and leaving you sounding hoarse, but you will not be mute.

If you (somehow) did physical damage to the vocal folds you would leave someone with a raspy, post-tracheotomy voice. The tongue and soft palate can shape words, but there's no airflow to make them with. Everything would sound like an exhalation. How you'd do this is questionable though, as to get to the vocal folds you'd have to put the arrow through a lot of blood vessels and much of the trachea. Surviveability is tricky.

If you damaged the mouth area you could get the opposite effect - vocal folds fine, tongue or soft palate affected - but you'd have to put something through their face to go that.

The other route you have (possibly simpler) is to avoid going down the physical route altogether and ascribe the muteness to PTSD. So your MC has the physical ability to speak, but they are traumatised to the point of not being able to. You'd need a pretty big or sudden trauma to cause this!

Hope this helps!

Thanks for all the info! I think I might go with the psychological aspect, since physically it would be pretty hard to do.