An adjustable vertebral body replacement implant and assembly includes a thin-walled cylindrical body configured to span over most of the length between intact vertebrae when damaged or diseased vertebrae have been removed. The cylindrical body defines a hollow interior with a plurality of bone-ingrowth apertures communicating with the interior. The replacement assembly further includes endplates configured to contact the adjacent vertebra and to engage the cylindrical body therebetween. The cylindrical body and the endplates include mating threads to permit adjustment of the overall height of the implant. A means for fixing the cylindrical body to the endplates is contemplated, which in one embodiment is a set screw for locking the components in place. In another embodiment, the means for fixing includes a crimping channel and notch defined in the endplates to be crimped onto the cylindrical body. A means for connecting the replacement implant to a longitudinal member is provided, which in one embodiment contemplates a clamp and screw assembly. In another embodiment, the means for connecting includes an arm projecting from the endplates with an opening to receive the longitudinal member therethrough.