Personally, I think the TSA went way the hell overboard on this one.
one time my parents were taking my children, niece and nephew to florida for a vacation.. they made my mother remove my disabled son's back and leg braces so they could check them.. the only metal on the braces are small d-rings for the straps. the rest of the brace is a solid plastic. i mean just looking at him you can tell why he needs the braces.