Abstract: The invention relates to a height-adjustable vertebral implant comprising a first essentially U-shaped cage which has recesses or holes and vertebral support surfaces which are formed at the cage. The first cage is encompassed and guided telescopically by a second, outer U-shaped cage, with the legs of the inner and outer cages being formed in such a manner that a continuous lateral opening is obtained. One end face each of the cages has upper and lower angular, tongue-like vertebral support surfaces as well as tooth-like locking projections which extend in the longitudinal direction. The inner and outer cages can be fixed in a pregiven end position relative to one another.