Fig. 1

Images of the biomechanical tests: a pattern graph of left lateral bending: 1 embedding block, 2 lumbosacral spine, 3 fixed base, 4 narrow load heads, 5 stable films; b Images of the AF group in the torsion test
Images of the biomechanical tests: a pattern graph of left lateral bending: 1 embedding block, 2 lumbosacral spine, 3 fixed base, 4 narrow load heads, 5 stable films; b Images of the AF group in the torsion test