The use of prostheses that are made of metal and components that conduct electricity poses a risk to people because there may be a dangerous accumulation of heat in the area where the electrodes are located, there may also be an irregular electrical conduction that generates burns.
You should always ask your specialist doctor and physiotherapist about the type of prosthesis you have in your body. Even pacemakers can be affected by the constant electrical pulses emitted by electrotherapy devices, so you should not hide the use of prostheses in the body.