15 June 2020 : Clinical Research
Comparative Three-Dimensional Finite Element Analysis of 4 Kinds of Pedicle Screw Schemes for Treatment of Adult Degenerative Scoliosis
Yang Zhou1ABE, Daqi Xin2CD, Zhuoting Lei3C, Yuan Zuo4CD, Yan Zhao4EG*DOI: 10.12659/MSM.922050
Med Sci Monit 2020; 26:e922050
Table 2 The maximum force values and positions of the screw-rod systems under 7 different work conditions of 4 screw models.
| Work condition | Maximum stress values (Mpa) of different screw models | |||
|---|---|---|---|---|
| Full-segment screw system (position) | Interval screw system (position) | Key vertebra screw system (position) | Strategic screw system (position) | |
| Upright | 74.514 (L1, left) | 75.782 (L2, left) | 70.91 (L5, right) | 71.728 (T12, left) |
| Forward flexion | 463.04 (L5, right) | 474.14 (L4, left) | 492.58 (L5, right) | 537.74 (L5, right) |
| Backward extension | 455.44 (L5, right) | 476.23 (L5, right) | 501.74 (L5, right) | 550.16 (L5, right) |
| Left lateral flexion | 385.92 (L5, right) | 486.37 (T12, left) | 424.83 (T12, left) | 495.85 (T12, left) |
| Right lateral flexion | 381.38 (L5, right) | 563.88 (T12, left) | 493.98 (T12, left) | 582.31 (T12, left) |
| Left axial rotation | 208.37 (T12, left) | 333.39 (T12, left) | 298.67 (T12, left) | 369.95 (T12, left) |
| Right axial rotation | 208.54 (T12, left) | 333.43 (T12, left) | 298.74 (T12, left) | 369.99 (T12, left) |
| L – lumbar vertebra; T – thoracic vertebra. | ||||