To improve the chances of successful fixation in osteopenic bone, cancellous bone stock may be augmented with cement to increase its stiffness and strength. More recently, the suitability of nonexothermic bioactive cements for pedicle screw augmentation has been investigated. Bioactive cements are osteoconductive, promoting bone growth directly on the cement surface without intervening fibrous tissue, therefore forming a strong bond between bone and implant like hydroxyapatitie composite resion cement which increases the initial load-bearing capacity of the implant-bone interface but more importantly increases the fatigue resistance of this interface. Using of a new designs of pedicle screw like Alligator expandable screw. Revision of pedicle screw :In patients in whom a solid fusion has not been achieved, pedicle screw salvage and revision may be necessary. Salvaging screw purchase in any bone can only be accomplished by using a larger diameter screw, by using a longer screw, by using a screw both larger in diameter and longer, by augmenting the failed hole, or by placing the screw in a new site. Techniques already developed for this purpose include drilling of a pilot hole in the broken screw and extracting it with a reverse thread extractor, and drilling a slot on the cut surface of the screw and extracting it by means of a flathead screwdriver. A simple and fast procedure, used in three recent cases, that completely preserves the integrity of both the pedicle and the screw hole, and thereby allows for the subsequent application of a new transpedicular stabilization system with screws of slightly larger diameter.