Person undergoing Transcutaneous Electrical Nerve Stimulation (TENS) in a hospital physiotherapy department, during assesment of pain control following damage to the radial nerve sustained in a road accident. Series of high-voltage, high- frequency electrical impulses are passed between the 2 electrodes on the forearm: the physiotherapist is seen adjusting their frequency & amplitude on the power supply unit. The technique has many applications in analgesia, being cheaper & safer than using drugs: it is not recommended for use on children or pregnant women. After an assesment period (up to 5 days), the patient may be able to continue treatment at home.