Table 5 Correlation between Pfirrmann classification and the degree of nerve root compression

0.020

− 0.193

0.000

0.888

0.180

1.000

− 0.527

− 0.670

− 0.333

 < 0.001*

 < 0.001*

0.018*

− 0.668

− 0.620

− 0.486

 < 0.001*

 < 0.001*

 < 0.001*

0.684

0.612

0.473

 < 0.001*

 < 0.001*

0.001*

− 0.576

− 0.605

− 0.619

 < 0.001*

 < 0.001*

 < 0.001*

0.643

0.602

0.675

 < 0.001*

 < 0.001*

 < 0.001*

− 0.564

− 0.554

− 0.539

 < 0.001*

 < 0.001*

 < 0.001*

0.651

0.642

0.557

 < 0.001*

 < 0.001*

 < 0.001*

− 0.457

− 0.610

− 0.576

0.001*

 < 0.001*

 < 0.001*

0.392

0.652

0.475

0.005*

 < 0.001*

 < 0.001*

− 0.327

− 0.529

− 0.560

0.020*

 < 0.001*

 < 0.001*

0.382

0.550

0.536

0.006*

 < 0.001*

 < 0.001*