@nykeyoungwsCan a PC with one hand use a shield? yes
— Mike Mearls (@mikemearls) September 6, 2015
@nykeyoungwsWith a weapon? I.e. the arm is enough to hold the shield? not effectively. I'd say you can carry and use one thing per hand. Can carry more but not use
— Mike Mearls (@mikemearls) September 6, 2015
Well if its just the hand and shield rules dont specify buckler, small, large etc it should be able to be modified with straps and buckles and be straped to the arm and the good hand holds the sword. I remember reading a story about a German knight who lost his hand and had it replaced with a metal prosthetic that could be locked onto his hand like a vice and he swore he was a better knight and had more kills with the prosthetic than before it.
Thank you for your story Lord Chris