These procedures are generally used to treat conditions such as persistent chest pain, phantom arm or leg pain, chronic pelvic pain and other persistent nerve pain. SCS is implemented in two parts. In the first part, the patient carries out a trial of the SCS whereby a (lead) will be connected to a portable external pulse generator. The patient will be given various combinations of electrical signals to assess if the pulses reduce their pain. This trial mimics the actual treatment. If the rial is successful, the entire SCS system (including the electrodes, leads, cables and pulse generator) will be implanted into the patients. An external remote controller communicates with the (device) in order to instruct the release of pulses. The patient is subsequently monitored after the entire SCS system is installed.