Originally Posted by idkfa
The reason why I ask is because of personal history with misdiagnosis. I was diagnosed with psoriasis when I was 3 years old and a dozen different doctors and specialists continued to prescribe treatments to this effect for almost 20 years. It turns out I have a form of dermatitis which was far easier to treat. I don't mean to get your hopes up but there are a lot of uninformed doctors out there.
EDIT: Psoriasis in extreme cases can cause arthritis-like symptoms at your joints. This may be a concern for the military.
I am in the military and there are many knee and joint issues because of the type of job the military intells so their reasoning and diagnosis maybe spot on.
If you want it bad enough I would consult more doctors, not military doctors and actually find out so you know what is going on so if you can join then do so [assuming you still want to at that point]. If you want it bad enough you'll get the answers you need but if you can't then don't feel bad as my grandfather could not service in the second world war during his life due to medical reasons and people didn't look down upon him as anything less than a honorable and respected man. Some can't serve due to medical conditions, its life but work at it and see what you can find out about your knees so you make the right decision.