The other day I was contemplating about the same - it would be cool if someone in the future tried to figure out what is happening with my body now.
But then the other thought crossed my mind… Perhaps nobody cares too much about it when doing autopsies and dissecting cadavers for scientific purposes, the same way few doctors really care about finding the root cause(s) of the illness(es) while we are still alive… 
No wonder that such situation allows alternative medicine to flourish, from total quacks like magnetic or crystal healers to more educated chiropractors.
Saying that, I’m leaning towards the idea that skeletomuscular problems might often be one of the primary but overlooked causes of apparently unrelated symptoms by either causing some disturbances in blood flow (leading to insufficient oxygen/nutrients delivery to various organs), spinal cord/nerve irritation, or simply holding muscles in spasm and through some feedback-like mechanism, which I don’t know about, overloading the sensory system. Perhaps it’s something simple, like muscles constantly sending intense electrochemical signal to the brain demanding immediate action/reaction to keep the body in balance, eventually overloading the brain and putting the whole body into some sort of fight-or-flight state without any real need.
My guess is that eventually the body has enough of wear-and-tear injuries to be unable to perform repair at the rate the injury is happening, and the body starts demonstrating all sorts of mysterious symptoms.
Perhaps similarly to the cancerous cells (sorry, my knowledge is very limited here), when they start multiplying at rate higher than the body’s ability to fight off, and then quickly overload the body’s defence mechanism in late stages.