As disturbed as I am that you'd ask about this on hacker news... it sounds like a classic connective tissue disorder, i.e. joint hypermobility or Ehlers Danlos

As disturbed as I am that you'd ask about this on hacker news... it sounds like a classic connective tissue disorder, i.e. joint hypermobility or Ehlers Danlos Syndrome. Your history of medical mismanagement is also typical of people with this problem: people will try to chase the problem around rather without identifying the underlying cause.