Abstract
Abstract
Background
Biomechanical characteristics of noncontinuous ACDF and noncontinuous CDA in the treatment of noncontinuous cervical degenerative disc disease were still unclear. The aim of this research is to compare the differences between these two kinds of treatment methods and to verify the effectiveness of Prodisc-C in noncontinuous CDA.
Methods
Eight FEMs of the cervical spine (C2–C7) were built based on CT images of 8 mild CDDD volunteers. In the arthroplasty group, we inserted Prodisc-C at C3/4 and C5/6. In the fusion group, CoRoent® Contour and NuVasive® Helix ACP were implanted at C3/4 and C5/6. Initial loads of 75 N were used to simulate the head weight and muscle forces. The application of 1.0 N m moment on the top on the C2 vertebra was used to create motion in all directions. Statistical analyses were performed using STATA version 14.0 (Stata Corp LP, College Station, Texas, USA). Statistical significance was set at P < 0.05.
Results
The IDPs in C2/3 (P < 0.001, P = 0.005, P < 0.001, P < 0.001), C4/5 (P < 0.001), and C6/7 (P < 0.001) of the intact group were significantly less than that in the fusion group in flexion, extension, lateral bending, and axial rotation, respectively. In addition, the IDPs in C2/3 (P < 0.001, P = 0.001, P < 0.001, P < 0.001), C4/5 (P < 0.001), and C6/7 (P < 0.001) of the arthroplasty group were significantly less than that in the fusion group in flexion, extension, lateral bending, and axial rotation, respectively. Contact forces of facet joints in C2/3 (P = 0.010) in the arthroplasty group was significantly less than that in the intact group. Contact forces of facet joints in C2/3 (P < 0.001), C4/5 (P < 0.001), and C6/7 (P < 0.001) in the arthroplasty group was significantly less than that in the fusion group. Contact forces of facet joints in C2/3 (P < 0.001), C4/5 (P < 0.001), and C6/7 (P < 0.001) in the intact group were significantly less than that in the fusion group.
Conclusions
Noncontinuous CDA could preserve IDP and facet joint forces at the adjacent and intermediate levels to maintain the kinematics of cervical spine near preoperative values. However, noncontinuous ACDF would increase degenerative risks at adjacent and intermediate levels. In addition, the application of Prodisc-C in noncontinuous CAD may have more advantages than that of Prestige LP.
Funder
China Scholarship Council
National Natural Science Foundation of China
Beijing Municipal Commission of Health and Family Planning
Publisher
Springer Science and Business Media LLC
Subject
Orthopedics and Sports Medicine,Surgery