Table 6 The von Mises stress of the structures in different lengths of titanium plates

Flexion

C4/C5 disc

1.417 ± 0.297

1.411 ± 0.257

1.422 ± 0.271

0.406

0.671

0.029

C6/C7 disc

1.483 ± 0.036

1.476 ± 0.045

1.455 ± 0.030

1.495

0.242

0.100

Bone graft

0.255 ± 0.040 ^{* #}

0.307 ± 0.025 ^#

0.400 ± 0.031

49.897

<  0.001

0.787

Titanium plate

57.886 ± 3.374 ^{* #}

48.363 ± 4.237 ^#

36.822 ± 1.049

109.670

<  0.001

0.890

Screw

32.983 ± 1.238 ^{* #}

42.075 ± 3.569 ^#

58.018 ± 3.083

202.663

<  0.001

0.938

Extension

C4/C5 disc

1.337 ± 0.027

1.333 ± 0.019

1.346 ± 0.032

0.619

0.546

0.044

C6/C7 disc

1.425 ± 0.027

1.419 ± 0.016

1.413 ± 0.018

0.751

0.482

0.053

Bone graft

1.527 ± 0.051 ^{* #}

1.668 ± 0.042 ^#

1.812 ± 0.053

84.109

<  0.001

0.862

Titanium plate

58.069 ± 6.173 ^{* #}

41.552 ± 3.822 ^#

24.791 ± 1.740

148.985

<  0.001

0.917

Screw

34.820 ± 1.386 ^{* #}

58.166 ± 3.206 ^#

95.603 ± 2.204

1653.432

<  0.001

0.992

Bending

C4/C5 disc

1.382 ± 0.038

1.426 ± 0.119

1.388 ± 0.041

0.957

0.397

0.066

C6/C7 disc

1.402 ± 0.030

1.415 ± 0.032

1.398 ± 0.020

0.960

0.395

0.066

Bone graft

1.522 ± 0.084 ^{* #}

1.868 ± 0.057 ^#

2.308 ± 0.055

349.902

<  0.001

0.963

Titanium plate

94.691 ± 1.859 ^{* #}

83.956 ± 2.769 ^#

73.790 ± 1.708

233.352

<  0.001

0.945

Screw

55.388 ± 1.090 ^{* #}

60.705 ± 1.258 ^#

66.406 ± 0.647

285.569

<  0.001

0.955

Rotation

C4/C5 disc

1.384 ± 0.047

1.378 ± 0.036

1.387 ± 0.038

0.112

0.895

0.008

C6/C7 disc

1.351 ± 0.170

1.292 ± 0.170

1.224 ± 0.080

1.912

0.167

0.124

Bone graft

1.620 ± 0.026 ^{* #}

1.714 ± 0.053 ^#

1.945 ± 0.041

161.710

<  0.001

0.923

Titanium plate

68.463 ± 2.529 ^{* #}

62.311 ± 2.526 ^#

57.824 ± 0.929

62.751

<  0.001

0.823

Screw

56.617 ± 1.467 ^{* #}

64.038 ± 1.663 ^#

75.025 ± 2.727

208.241

<  0.001

0.939