The biomechanical effects of S-type dynamic cage using Ti and PEEK for ACDF surgery on cervical spine varying loads

Abstract

Anterior cervical discectomy with fusion (ACDF) is the common method to treat the cervical disc degeneration. The most serious problems in the fusion cages are adjacent disc degeneration, loss of lordosis, pain, subsidence, and migration of the cage. The objective of our work is to develop the three-dimensional finite element (FE) model from C3-C6 and virtually implant a designed S-type dynamic cage at C4-C5 segment of the model. The dynamic cage design will provide mobility in the early stage after ACDF surgery. Titanium (Ti) and PEEK (polyether ether ketone) were used as the material property for the cages. We applied the physiological motions at different loads from 0.5, 1, 1.5, 2.0 Nm to evaluate the dynamic cage design and the biomechanical performances of the designed S-type dynamic cage. It was observed that in all the loading condition the range of motion in the adjacent level was maintained and the maximum stress at the adjacent disc was reduced. The clinical significance of the S-type dynamic cage is better stress profile at the fusion level and adjacent segments which translates into higher rate of fusion, lower risk of cage subsidence, lower risk of adjacent segment degeneration, and good mechanical stability.

Biomechanical analysis of a single-level customized cage screw fixation for anterior cervical discectomy and fusion in the cervical spine: an in-silico study

“…The usual surgical choice of customized cage fixation is anterior cervical discectomy and fusion (ACDF) for cervical spondylosis with disc herniation or other ventrally generated cervical infections that are not identified by conventional therapy [1][2][3][4]. Age-related wear and tear on the cervical spinal discs may lead to degenerative alterations.…”

“…The mid-to-lower cervical spine, notably the region between the C4 and C7 vertebrae, is where cervical disc degeneration is most often observed, according to the study. This area of the spine is particularly susceptible to degenerative alterations because of its mobility and the stress put on it during movement [2,5,6]. A surgery called Anterior cervical decompression and fusion (ACDF) for cage fixation is routinely carried out in treatment of degenerative diseases of the cervical spine, such as the progressive degradation of the spinal discs, vertebrae and other structures in the cervical spine [2,7,8].…”

“…This area of the spine is particularly susceptible to degenerative alterations because of its mobility and the stress put on it during movement [2,5,6]. A surgery called Anterior cervical decompression and fusion (ACDF) for cage fixation is routinely carried out in treatment of degenerative diseases of the cervical spine, such as the progressive degradation of the spinal discs, vertebrae and other structures in the cervical spine [2,7,8]. The risk factors concerning the adjacent segment degeneration (ASD) and diseases can be reduced to larger extent by maintaining the cervical lordosis during ACDF for cage fixation treatments [2,9,10].…”

“…A surgery called Anterior cervical decompression and fusion (ACDF) for cage fixation is routinely carried out in treatment of degenerative diseases of the cervical spine, such as the progressive degradation of the spinal discs, vertebrae and other structures in the cervical spine [2,7,8]. The risk factors concerning the adjacent segment degeneration (ASD) and diseases can be reduced to larger extent by maintaining the cervical lordosis during ACDF for cage fixation treatments [2,9,10]. The safe and successful cage fixation for ACDF surgery benefits patients with cervical disc degenerative disease by easing their discomfort and regaining function [3,4].…”

“…The safe and successful cage fixation for ACDF surgery benefits patients with cervical disc degenerative disease by easing their discomfort and regaining function [3,4]. By using cage implants to anchor the neighbouring vertebrae, cage prevents mobility between the vertebrae [2,4]. With a broader anterior surface and a smaller posterior surface that fits tightly between the neighbouring vertebral bodies, the wedge-shaped trapezoidal interbody cage is intended to imitate the natural architecture of the intervertebral disc.…”