FWIW, after Cora's leg was repaired, my vet mentioned that when the break had healed, we should discuss removing the hardware (plate, wires, screws) because OS can occur at the site of the hardware. I thought we'd probably leave it in place, because it takes years for the OS to appear, and she was almost 10 when the leg broke. As it happened, the OS turned up before she had healed; I think it was probably there all along and just didn't show up on the x-rays.
Was hardware left in place during the repair?