Hi, thanks for writing to HCM.
I don't think that your numbness
in the fingers is due to the titanium plate. This is because, if there is any compression of the nerves by the plate, it will manifest immediately after surgery and not after 4 years after the plate insertion.
So, I suspect some other cause for your numbness in the fingers. A detailed clinical examination and Nerve conduction studies are needed to establish the diagnosis of your problem.
Hope this information is helpful. Good day