Probably the majority of patients were railroad employees that suffered on-the-job inures. Brakemen and conductors probably incurred the most series injuries -- from mangled hands to loss of whole limbs. Shop men might receive similar injuries. But engineers and firemen might be scalded by hot water or steam.
During a long spread of decades the railroads often found employment for men who due to injuries could no longer do their former work. Amputees might become crossing or junction flagmen, might become tower operators; others might be able to assume clerical duties in a depot or other railroad office.
Brian Norden.