Systematic Reviews
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Orthop. Oct 28, 2019; 10(11): 394-403
Published online Oct 28, 2019. doi: 10.5312/wjo.v10.i11.394
Magnetically controlled growing instrumentation for early onset scoliosis: Caution needed when interpreting the literature
Kenneth Aaron Shaw, Justin M Hire, Scott Kim, Dennis P Devito, Michael L Schmitz, Joshua S Murphy
Kenneth Aaron Shaw, Department of Orthopaedic Surgery, Dwight D. Eisenhower Army Medical Center, Fort Gordon, GA 30905, United States
Justin M Hire, Department of Orthopaedic Surgery, General Leonard Wood Army Community Hospital, Fort Leonard Wood, MO 65473, United States
Scott Kim, University of Tennessee Health Science Center, Memphis, TN 38163, United States
Dennis P Devito, Michael L Schmitz, Joshua S Murphy, Department of Pediatric Orthopaedic Surgery, Children’s Healthcare of Atlanta, Scottish Rite Campus, Atlanta, GA 30342, United States
Author contributions: Shaw KA, Devito DP, Schmitz ML and Murphy JS designed research; Shaw KA, Hire JM and Kim S performed research; Shaw KA analyzed data; Shaw KA, Hire JM and Murphy JS wrote the paper.
Conflict-of-interest statement: Each author certifies that he or she has no commercial associations that might pose a conflict of interest in connection with the submitted article. The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or reflecting the views of the Department of Defense or US Government.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (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: Kenneth Aaron Shaw, MD, Assistant Professor, Surgeon, Department of Orthopaedic Surgery, Dwight D. Eisenhower Army Medical Center, 300 East Hospital Road, Fort Gordon, GA 30905, United States. Shaw.aaron82@gmail.com
Telephone: +1-706-7876158 Fax: +1-706-7872901
Received: May 5, 2019
Peer-review started: May 8, 2019
First decision: July 31, 2019
Revised: September 6, 2019
Accepted: October 7, 2019
Article in press: October 7, 2019
Published online: October 28, 2019
Processing time: 201 Days and 15.7 Hours
Abstract
BACKGROUND

Magnetically controlled growing rods (MCGR) are a novel treatment option for early onset scoliosis (EOS). Although the complication profile with MCGR use has been reviewed, these reviews do not take into account important implants modifications, termed iterations, that were made due to early on postoperative complications is not well reported or understood.

AIM

To assess the effect of MCGR implant iterations on post-operative complications in EOS.

METHODS

A systematic review was performed to identify studies investigating MCGR specifically for the treatment of EOS, refined to those reporting the implant iteration, specifically the incorporation of the keeper plate to the implant design. Articles with mixed implant iteration usage were excluded. Complications following surgery were recorded as well as potential risk factors and compared between implant cohorts.

RESULTS

Although 20 articles were identified for inclusion, 5 included mixed implant iteration leaving a total of 271 patients identified through 15 clinical studies that met inclusion criteria. The average follow-up was 25.4-mo. Pre-keeper plate implants were utilized in 3 studies with a total of 49 patients. Overall, 115 (42.4%) post-operative complications were identified, with 87% defined as major. The addition of the keeper plate significantly decreased the rate of post-operative complications per study (35.7% vs 80.6%, P = 0.036), and the rate of distraction failure (8.1% vs 40.8%, P = 0.02). Unplanned reoperation occurred in 69 (26.7%) patients but was not different between implant iteration cohorts (25.5% without keeper plate vs 27.1% with keeper plate, P = 0.92).

CONCLUSION

MCGR for EOS has a cumulative complication rate of 42.4% but this is significantly reduced to 35.7% when reviewing only keeper-plate enabled implants. However, 25% of published articles included mixed implant iterations. Future studies should discern between implants iterations when reporting on the usage of MCGR for EOS.

Keywords: Complications; Early onset scoliosis; Magnetically controlled growing instrumentations; Keeper plate; Reoperation; Systematic review

Core tip: Magnetically controlled growing rods (MCGR) are a novel treatment approach for early onset scoliosis which is gaining increases clinical usage. Since its introduction, numerous modifications have been implemented to improve the performance of the construct, however, these modifications are often over-looked in current published series. This study evaluated the effect of the addition of the keeper plate to MCGR, finding that it had a significant impact on decreasing the rate of post-operative distraction failures. Despite the impact of this modification, 25% of published articles included mixed implant designs in their series, potentially inflating reported complication rates.