Surgical sacral anchor implant

In a surgical implant capable of securing a spinal tensioning cable to the sacrum, the improvement wherein said implant comprises two laminar and substantially coplanar prongs which are sized and shaped for insertion into a spinal disc space and are rigidly secured together at their bases by a bridge portion which extends away from the prongs in a direction that makes an angle of not more than 90.degree. with the plane of the prongs and on the side on which the prongs lie, and means for securing to the bridge portion a spinal tensioning cable extending substantially in the said direction in which the bridge portion extends.