At the Department of Orthopedics, Humboldt University School of Medicine, Charité Hospital, the three-piece disk endoprosthesis SB Charité of the modular type, which works according to the low-friction principle, has been developed combining the advantages of a beneficial effect on the patient's complaints by simultaneous distraction in the vertebral segment, and of achieving movement within the physiological range. So far, this disk endoprosthesis consisting of two cover plates made of implantat steel or titanium sheet, which are fixed without cement, as well as a moveable polyethylene sliding core being vertically adjustable, has been implanted in sixteen patients. The therapeutic results show that it is possible with this method to replace the nucleus pulposus, thus providing, in addition to conventional nucleotomy and segment fusion, another therapeutic alternative for lumbar disk lesions.