For a prospective cohort study, the goal of the study was to determine which surgical parameters influence adjacent segment kinematics following anterior cervical discectomy and fusion (ACDF) as evaluated by biplane radiography. Previous research looked into the influence of surgical variables on spine kinematics as a possible cause of adjacent segment disease (ASD). Static flexion-extension radiographs were employed in those investigations to assess the range of motion. On the other hand, Static radiograph measures are known to be untrustworthy.
Furthermore, the effect of ACDF on neighbouring segment axial rotation was not evaluated in those investigations. Preoperatively and 1 year after ACDF, patients had continuous cervical spine flexion/extension and axial rotation motions collected at 30 pictures per second in a dynamic biplane radiography system. A previously proven tracking approach matched digitally reconstructed radiographs derived from subject-specific CT scans to biplane radiographs. The tracking procedure was used to calculate dynamic kinematics, postoperative segmental kyphosis, and disc distraction. On postoperative radiographs, the plate-to-disc distance was assessed. The medical data was used to determine the type of graft. Researchers used multivariate linear regression to find surgical parameters linked to changes in neighboring segment kinematics 1 year after surgery. A subsequent analysis compared neighboring segment kinematics between the surgical parameters and previously determined thresholds linked to adjacent segment degeneration. About 59 patients completed preoperative and postoperative testing. None of the surgical parameters were linked to changes in neighboring segment flexion/extension or axial rotation range of motion (all P>0.09). There were no changes in the secondary analysis between neighboring segment kinematics and surgical variables (all P>0.07). Short-term changes in neighboring segment kinematics that represent the hypermobility predicted to lead to the development of ASD were not correlated with parameters related to surgical technique following ACDF for cervical spondylosis.
