A spinal fusion implant has a parallelepiped main body with a rotatably mounted retention plate secured to its distal end. The distal retention plate has a first position co-planar with the main body and a second, deployed position normal to the plane of the main body. The distal retention plate is in the first position when the main body is inserted between adjacent vertebral bodies and is in the second position after the main body is inserted between adjacent vertebral bodies. In further embodiments, a proximal retention plate is permanently deployed in normal relation to the main body or both the distal and proximal retention plates are rotatably mounted and both are deployed co-planar to the main body before insertion and normal to the main body after insertion.