Bone spurs...interesting comment.
I have sat on USN medical boards which decided things such as being physically fit for duty. We made the distinction between NCD (Not Considered Disqualifying) and CD (Considered Disqualifying) for entry into the Navy/USMC and, more often, whether or not a person would be fit for entry into specialty fields, such as aviation. BUDs, electronics, etc.
The pre-existing conditions would sometimes exclude someone from entry into any branch of the service. Some of those conditions could be safety concerns, some could be training concerns (could they be expected to complete training) and how much would expected treatment cost over a lifetime.
Oddly enough, if those conditions were discovered after entry into the Armed Forces, they may not always be CD.
As an example, being color blind would exclude entry into aviation and electronics simply due to safety concerns.
Sometimes certain anthropometric measurements would be used to determine which, if any, aircraft could be safely piloted by folks with anthro measurements out of spec for a given platform. As an example, dudes/dudettes who wanted to fly ejection seat equipped aircraft had to have a heel to knee measurement within standards. This was mainly due to the rapid acceleration of the seat....if the lower leg bone was too long, 'seat slap' would happen, with the likely end result of a broken femur. Most of the too tall folks about to enter aviation would mostly end up in multi engine or rotary wing aircraft.
With respect to bone spurs and flat feet, for example, ENTRY into the Armed Forces was routinely denied (most likely due to $$$ amount of continued treatment) and the applicant had no choice.