There are no warnings or precautions for using the geko® device in proximity to surgical metal work. The only problem a user might encounter is if the metal work/surgery has damaged the common peroneal nerve and there is peripheral neuropathy. The device stimulates the common peroneal nerve which causes the muscle contraction and increased blood flow so if your nerve is damaged it might not stimulate the muscle. In this event you would suffer no ill effects. However, seek advice from a healthcare professional to check for neuropathy damage.