Retrospective Study
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Dec 16, 2021; 9(35): 10850-10860
Published online Dec 16, 2021. doi: 10.12998/wjcc.v9.i35.10850
Adjacent segment disease following Dynesys stabilization for lumbar disorders: A case series of mid- and long-term follow-ups
Kuan-Ju Chen, Chien-Ying Lai, Lu-Ting Chiu, Wei-Sheng Huang, Pang-Hsuan Hsiao, Chien-Chun Chang, Cheng-Jyh Lin, Yuan-Shun Lo, Yen-Jen Chen, Hsien-Te Chen
Kuan-Ju Chen, Chien-Ying Lai, Department of Orthopedic Surgery, China Medical University Hospital, Taichung City 404, Taiwan
Chien-Ying Lai, Spine Center, China Medical University Hospital, Taichung City 404, Taiwan
Lu-Ting Chiu, Management Office for Health Data, China Medical University Hospital, Taichung City 404, Taiwan
Lu-Ting Chiu, College of Medicine, China Medical University, Taichung City 404, Taiwan
Wei-Sheng Huang, School of Chinese Medicine, China Medical University, Taichung City 404, Taiwan
Pang-Hsuan Hsiao, Chien-Chun Chang, Cheng-Jyh Lin, Yuan-Shun Lo, Yen-Jen Chen, Hsien-Te Chen, Department of Orthopedic Surgery, China Medical University Hospital, China Medical University, Taichung City 404, Taiwan
Pang-Hsuan Hsiao, Chien-Chun Chang, Yuan-Shun Lo, Yen-Jen Chen, Hsien-Te Chen, Spine Center, China Medical University Hospital, China Medical University, Taichung City 404, Taiwan
Chien-Chun Chang, Degree Program of Biomedical Science and Engineering, National Chiao Tung University, Hsinchu City 300, Taiwan
Chien-Chun Chang, Department of Biological Science and Technology, National Chiao Tung University, Hsinchu City 300, Taiwan
Yuan-Shun Lo, Department of Orthopedic Surgery, China Medical University Beigang Hospital, Yunlin County 651, Taiwan
Yuan-Shun Lo, Graduate Institute of Precision Engineering, National Chung Hsing University, Taichung City 404, Taiwan
Yen-Jen Chen, School of Medicine, China Medical University, Taichung City 404, Taiwan
Hsien-Te Chen, Department of Sport Medicine, College of Health Care, China Medical University, Taichung City 404, Taiwan
Author contributions: Chen KJ and Lai CY conceptualized the study; Chen HT conceptualized, reviewed, and supervised the entire study; Chen KJ wrote and reviewed the manuscript; Chen KJ and Lai CY contributed equally to the work; all authors have read and approved the final version of the submitted manuscript.
Institutional review board statement: The study was approved by our institutional review board, Research Ethics Committee China Medical University and Hospital, Taichung, Taiwan (Protocol No.: CMUH108-REC2-133).
Informed consent statement: The institutional review board waived the need for informed consent.
Conflict-of-interest statement: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. The authors declare no conflict of interest.
Data sharing statement: All data generated or analyzed during this study are included in this published article and its supplementary information files.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Hsien-Te Chen, MD, PhD, Doctor, Surgeon, Department of Orthopedic Surgery, China Medical University Hospital, China Medical University, No. 2 Xueshi Rd., North District, Taichung City 404, Taiwan. d2326@mail.cmuh.org.tw
Received: May 4, 2021
Peer-review started: May 4, 2021
First decision: July 15, 2021
Revised: August 4, 2021
Accepted: September 16, 2021
Article in press: September 16, 2021
Published online: December 16, 2021
Processing time: 219 Days and 18 Hours
Abstract
BACKGROUND

Radiologic adjacent segment degeneration (ASDeg) can occur after spinal surgery. Adjacent segment disease (ASDis) is defined as the development of new clinical symptoms corresponding to radiographic changes adjacent to the level of previous spinal surgery. Greater pre-existing ASDeg is generally considered to result in more severe ASDis; nonetheless, whether the ASDeg status before index surgery influences the postoperative risk of revision surgery due to ASDis warrants investigation.

AIM

To identify possible risk factors for ASDis and verify the concept that greater preexisting ASDeg leads to more severe ASDis.

METHODS

Data from 212 patients who underwent posterior decompression with Dynesys stabilization from January 2006 to June 2016 were retrospectively analyzed. Patients who underwent surgery for ASDis were categorized as group A (n = 13), whereas those who did not were classified as group B (n = 199). Survival analysis and Cox proportional hazards models were used to compare the modified Pfirrmann grade, University of California-Los Angeles grade, body mass index, number of Dynesys-instrumented levels, and age.

RESULTS

The mean time of reoperation was 7.22 (1.65–11.84) years in group A, and the mean follow-up period was 6.09 (0.10–12.76) years in group B. No significant difference in reoperation risk was observed: Modified Pfirrmann grade 3 vs 4 (P = 0.53) or 4 vs 5 (P = 0.46) for the upper adjacent disc, University of California-Los Angeles grade 2 vs 3 for the upper adjacent segment (P = 0.66), age of < 60 vs > 60 years (P = 0.9), body mass index < 25 vs > 25 kg/m2 (P = 0.3), and sex (P = 0.8).

CONCLUSION

Greater preexisting upper ASDeg was not associated with a higher rate of reoperation for ASDis after Dynesys surgery. Being overweight tended to increase reoperation risk after Dynesys surgery for ASDis.

Keywords: Adjacent segment degeneration; Adjacent segment disease; Degenerative lumbar spondylolisthesis; Dynamic stabilization; Dynesys; Spinal stenosis

Core Tip: Preoperative degeneration status of the adjacent segment did not affect the rate of mid- and long-term follow-up for adjacent segment disease. Dynesys is a reliable implant with respect to preserving the motion of the adjacent segment and reducing the progression of adjacent segment disease.