The invention relates to an intervertebral fusion implant (1) for fusing two vertebrae (52, 53). The intervertebral fusion implant for fusing two vertebrae (52, 53) comprises an upper bearing body (2) for placement on a lower end plate of a vertebra (52) and opposing this a lower bearing body (3) for placement on an upper end plate of a vertebra (53), and an intermediate piece (6) arranged between the bearing bodies (2, 3), wherein the intermediate piece is designed as a claw coupling (9), which in an engaged position engages the two bearing bodies (2, 3) in a rotationally fixed manner against one another, wherein in an open position of said claw coupling (9) the bearing bodies (2, 3) are freely moveable against one another, wherein the claw coupling (9) is actuated automatically and has a plastic locking body (10) as the actuating element, which locking body in its initial position holds the claw coupling (9) open and is slowly deformable under a load force transferred from the one vertebra (52) onto the other vertebra (54) until it reaches a final engaged position in which the claw coupling (9) is closed. Because of the slow fusion of the vertebrae (52, 53), the patient does not notice the restriction of movement in his spinal column and his musculoskeletal system can slowly accustom itself to the change.
