Biomechanical Study on Contiguous Three-Level Cervical Hybrid Surgery and Anterior Cervical Discectomy and Fusion / 医用生物力学

ABSTRACT

Objective To compare the biomechanical effects of contiguous three-level cervical Hybrid surgery[anterior cervical discectomy and fusion (ACDF) + cervical disc arthroplasty ( CDA)] and three-level ACDF. Methods The finite element model of C1-T1 cervical-thoracic spine was developed based on CT data. Three models were simulated by the implantation of Prestige LP and Zero-P prostheses, including two Hybrid models (AFA, Prestige LP implanted at C3-4 and C5-6 segments and Zero-P implanted at C4-5 segment; FAF, Zero-P implanted at C3-4 and C5-6 segments and Prestige LP implanted at C4-5 segment) and three-level ACDF model(FFF). The changes in range of motion (ROM) of adjacent levels during flexion, extension, lateral bending and axial rotation, the overall ROM, as well as the intradiscal pressure ( IDP) and facet contact force ( FCF) of adjacent levels were compared. Results The ROM in adjacent levels and the overall ROM of the AFA modelwere closer to the intact model, and the maximum increases in the ROM of the adjacent levels for the FAF and FFF models were 15. 0% and 23. 4% , respectively. For AFA, FAF and FFF models, the maximum increases in the maximum IDP of adjacent levels were 19. 0% , 66. 7% , 147. 6% , and the maximum increases in FCF were 17. 4% , 55. 7% , 80. 1% , respectively. Conclusions This study provides biomechanical basis for three-level cervical Hybrid surgery in treating patients with the contiguous three-level cervical degenerative disc disease.