Rheumatism

In the end, what would keep Adam from his carriage making work and make him call in his invalid pension was his issues with rheumatism. However, for Civil War soldiers, rheumatism was an umbrella term that covered anything that had the symptoms of joint pain and inflammation. 

Today's doctors posit that most cases of rheumatism were in fact, rheumatic fever (caused by illnesses like strep throat) and about 280,000 Union soldiers apparently suffered from it. Adam himself claims to have first gotten in around the time of the Battle of Cross Keys, near the middle of his service period.

Unfortunately for Adam, it seems that treatments for rheumatism were quite lacking and ineffective, essentially leaving only opiates to dull the pain and compresses to sooth the inflammation. So it is likely that all those years he was a coach maker he suffered to some extent. 

(Shroeder-Lien)