Percutaneous nuclectomy according to the Onik method is an avantgarde method used to remove the intervertebral disc by percutaneous access and with closed surgery. The instrumentation and the procedure are simple. The main feature is the smaller diameter of the probe (2mm) which fragments and aspires the small chips of pulpy nucleus. It reduces the risk of discitic infections (occurring in various percentages with all methods of percutaneous discectomy) because the hole in the anulus, being small, closes spontaneously after the probe is removed. Moreover postoperative acute lumbar pain has been reported to occur less frequently. This method is carried out under local anesthesia, with radioscopic and intraoperative discographic monitoring. By consulting this atlas orthopaedists, neurosurgeons and neuroradiologists may learn this method easily, because every detail is clearly presented and illustrated with a great number of coloured pictures.