PMC9500315_01
(A) Photo of the preoperative moment-balanced traction, (B) lateral view of preoperative cervical X-ray, C2-C5 Cobb angle was -53.2 , (C) X-ray after the moment-balanced traction, (D) lateral view of cervical spine at three-month follow-up, Cobb angle of C2-C5 was -3.3 .
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F1
Preoperative moment-balanced traction was performed to stretch and relax the anterior muscles for 4 days; photo and X-ray were taken before and after the moment-balanced traction (Figures 1A-C). A three-month follow-up demonstrated that the postoperative Cobb angle of C2-C5 was maintained at -3.3  (Figure 1D) compared with the preoperative C2-C5 Cobb angle of -53.2  (Figure 1B).
Schematics of the instrument configurations used in the ACDF surgery.
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F2
Table 1. The cervical ventral plate is manufactured by Depuy Synthes (Raynham, MA, United States) and the cervical ventral plate and fixation screws are from Medtronic (Memphis, TN, United States), as shown in Figure 2.
Segmentation of the trabecular bone and cortical bone in the vertebra.
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F3
Following the representation of the trabecular bone volume, a layer of triangular prism elements was offset from the outer surface, corresponding to the cortex of each vertebra, 0.28 mm thickness for the cervical vertebrae and 0.24 mm for the thoracic vertebrae (Figure 3).
Graphical representation of the intervertebral disc (IVD) consisting of nucleus pulposus (NP) and anulus fibrosus (AF).
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F4
Intervertebral discs (IVDs) were reshaped based on the superior and inferior surfaces of the adjacent vertebral bodies, in which the anatomic structure including the inner nucleus pulposus and outer anulus were reconstructed, shown in Figure 4.
Anatomical schematics of ligaments and truss elements in the FEA model.
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F5
Figure 5 illustrates both the attachment of ligaments and the graphical representation in the FE model, the transverse area of each ligament and mechanical properties are listed in Table 4.