First of all, you need to bring all the case files related to your fracture and external fixation brace. This will help the security personnel understand your condition and determine if the information is compliant with airline regulations.
Secondly, if you need to use crutches or other assistive devices during your trip, it is recommended that you have them ready and in your luggage before you go through security. These items may be required to be checked separately or may be subject to a security check as you pass through security.
Finally, if you have items such as metal plates or steel pins fitted following surgery for a broken bone, you may need to carry a diagnostic certificate signed by your doctor certifying that these items are necessary medical equipment and detailing their location and materials. This will help security personnel understand the necessity of these items for you and assist you.
In short, if you are well-prepared according to the airline's rules and security requirements, you should be able to pass through airplane security. If you have any questions or need more help, talk to your doctor and the airline.