Case Report
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Orthop. Aug 18, 2023; 14(8): 651-661
Published online Aug 18, 2023. doi: 10.5312/wjo.v14.i8.651
Metallosis with spinal implant loosening after spinal instrumentation: A case report
Yiu Hin Kwan, Hong Lee Terry Teo, Shree Kumar Dinesh, Wee Lim Loo
Yiu Hin Kwan, Hong Lee Terry Teo, Shree Kumar Dinesh, Wee Lim Loo, Department of Orthopaedic Surgery, Changi General Hospital, Singapore 529889, Singapore
Author contributions: All authors contributed to the study conception and design; Loo WL conceptualized the study; Kwan YH collected and compiled the data; Kwan YH worte the first draft and final version of the manuscript; all authors commented on previous versions of the manuscript, and read and approved the final manuscript.
Informed consent statement: Informed written consent was obtained from the patient for the publication of this report and any accompanying images.
Conflict-of-interest statement: The authors declare that they have no conflict of interest to disclose. The authors declare that no funds, grants, or other support were received during the preparation of this manuscript.
CARE Checklist (2016) statement: The authors have read the CARE Checklist (2016), and the manuscript was prepared and revised according to the CARE Checklist (2016).
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: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Yiu Hin Kwan, MBBS, Doctor, Department of Orthopaedic Surgery, Changi General Hospital, 2 Simei Street 3, Singapore 529889, Singapore. yiuhin@gmail.com
Received: April 24, 2023
Peer-review started: April 24, 2023
First decision: June 1, 2023
Revised: June 26, 2023
Accepted: August 1, 2023
Article in press: August 1, 2023
Published online: August 18, 2023
Processing time: 114 Days and 22 Hours
Abstract
BACKGROUND

Spinal metallosis is a rare complication following spinal instrumentation whereby an inflammatory response to the metal implants results in the development of granulomatous tissue.

CASE SUMMARY

We describe the case of a 78-year-old woman who had recurrence of back pain 5 years after lumbar spine posterior decompression and instrumented fusion. Lumbar spine radiographs showed hardware loosening and magnetic resonance imaging showed adjacent segment disease. Revision surgery revealed evidence of metallosis intraoperatively.

CONCLUSION

Spinal metallosis can present several years after instrumentation. Radiography and computed tomography may demonstrate hardware loosening secondary to metallosis. Blood metal concentrations associated with spinal metallosis have yet to be established. Hence, metallosis is still an intraoperative and histopathological diagnosis. The presence of metallosis after spinal instrumentation likely indicates a more complex underlying problem: Pseudarthrosis, failure to address sagittal balance, infection, and cross-threading of set screws. Hence, identifying metallosis is important, but initiating treatment promptly for symptomatic implant loosening is of greater paramount.

Keywords: Metallosis; Spine; Instrumentation; Implant loosening; Corrosion; Case report

Core Tip: This paper describes a rare case of metallosis after spinal instrumentation and discusses the methods of diagnosing and risk factors contributing to spinal metallosis. A review of the current literature as presented in this paper demonstrates the scarcity of studies on spinal metallosis after spinal instrumentation, despite the fact that a diagnosis of spinal metallosis should be promptly identified and treated by revision surgery. It is also important to understand that the presence of metallosis after spinal instrumentation likely indicates a more complex underlying problem, such as instability of the spinal implants.