Biomechanical evaluation of adjacent segment degeneration after one- or two-level anterior cervical discectomy and fusion versus cervical disc arthroplasty: A finite element analysis

Wenbin Hua; Jinggang Zhi; Bingjin Wang; Wencan Ke; Wengang Sun; Shuhua Yang; Li Li; Cao Yang

doi:10.1016/j.cmpb.2020.105352

Biomechanical evaluation of adjacent segment degeneration after one- or two-level anterior cervical discectomy and fusion versus cervical disc arthroplasty: A finite element analysis

Comput Methods Programs Biomed. 2020 Jun:189:105352. doi: 10.1016/j.cmpb.2020.105352. Epub 2020 Jan 21.

Authors

Wenbin Hua¹, Jinggang Zhi², Bingjin Wang¹, Wencan Ke¹, Wengang Sun³, Shuhua Yang¹, Li Li⁴, Cao Yang⁵

Affiliations

¹ Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
² State Key Lab of Digital Manufacturing Equipment and Technology, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
³ Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
⁴ State Key Lab of Digital Manufacturing Equipment and Technology, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China. Electronic address: lili_em@hust.edu.cn.
⁵ Department of Orthopaedics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China. Electronic address: yangcao1971@sina.com.

PMID: 31991316
DOI: 10.1016/j.cmpb.2020.105352

Abstract

Background and objective: To compare the biomechanical changes of adjacent segment degeneration (ASD) after one- or two-level anterior cervical discectomy and fusion (ACDF) versus cervical disc arthroplasty (CDA).

Methods: A three-dimensional finite element (FE) model of intact C2-C7 segments was constructed and validated. In the one-level surgery model, the cage with plate implant or Prestige LP cervical disc prosthesis were integrated at C5-C6 segment into the FE model; while in the two-level surgery model, the prostheses were integrated at both C4-C5 and C5-C6 segments into the FE model. A pure moment of 1.0 Nm combined with a follower load of 73.6 N were imposed on C2 to investigate the flexion-extension, lateral bending, and axial rotation of different segments in the FE model. The segmental range of motion (ROM) and intradiscal pressure of the surgery models were investigated and compared with the intact model.

Results: In the one-level model of ACDF, the ROM at C5-C6 was decreased, the ROM and intradiscal pressure at C4-C5 and C6-C7 segments were increased. In the two-level model of ACDF, the ROM at C4-C5 and C5-C6 were decreased, the ROM and intradiscal pressure at C3-C4 and C6-C7 were increased. However, in both one- and two-level models of CDA, the ROM of surgery segments were preserved, avoiding the increase of the ROM and intradiscal pressure at the adjacent segments.

Conclusions: Abnormal ROM and intradiscal pressure at the adjacent segments may contribute to the higher risk of ASD after ACDF compared with CDA.

Keywords: Adjacent segment degeneration; Biomechanical; Cervical; Finite element; Intradiscal pressure; Range of motion; Surgery.

MeSH terms

Arthroplasty*
Biomechanical Phenomena / physiology*
Cervical Vertebrae / pathology*
Cervical Vertebrae / surgery*
Diskectomy*
Finite Element Analysis
Humans
Imaging, Three-Dimensional
Models, Anatomic
Range of Motion, Articular / physiology
Spinal Fusion*