
==== Front
Global Spine J
Global Spine J
spgsj
GSJ
Global Spine Journal
2192-5682
2192-5690
SAGE Publications Sage CA: Los Angeles, CA

10.1177_21925682241227944
10.1177/21925682241227944
Letters to the Editor
Letter to the Editor Concerning “Implant-Related Complications After Spinal Fusion: A Multicenter Study.” by Koshimizu et al.
Wang Zhiwei MD 1*
Hua Yu MD 1*
Cao Changqing MD 1
1 Department of Spine Surgery, Yantai Hospital of Shandong Wendeng Orthopaedics & Trauma Tology , Yantai, China
Changqing Cao, MD, Department of Spine Surgery, Yantai Hospital of Shandong Wendeng Orthopaedics & Trauma Tology, Lusi Road, Laishan Economic Development Zone, Yantai 264000, China. Email: caochangqing2023@163.com
* These authors contributed to the work equally and should be regarded as co-first authors.

13 1 2024
6 2024
14 5 16801681
© The Author(s) 2024
2024
AO Spine, unless otherwise noted. Manuscript content on this site is licensed under Creative Commons Licenses
https://creativecommons.org/licenses/by-nc-nd/4.0/ This article is distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 License (https://creativecommons.org/licenses/by-nc-nd/4.0/) which permits non-commercial use, reproduction and distribution of the work as published without adaptation or alteration, without further permission provided the original work is attributed as specified on the SAGE and Open Access pages (https://us.sagepub.com/en-us/nam/open-access-at-sage).

typesetterts10
==== Body
pmcTo the Editor,

We recently read the study conducted by Ye et al. 1 with considerable interest. While the research offers valuable insights into the occurrence and causes of implant-related complications, we would like to highlight some methodological considerations that may have influenced the study’s results.

One major concern is the study’s disregard for the potential influence of comorbidities and surgical variables on implant-related complications. A plethora of literature supports the notion that comorbidities and surgical variables significantly impact the incidence and nature of postoperative complications. For example, a study by John et al. 2 shows that comorbidities such as diabetes and obesity significantly heighten the risk of complications and reoperation following spinal fusion surgery. Similarly, a study by Rajaee et al. 3 suggests that surgical variables like surgical duration, intraoperative blood loss, and procedure complexity considerably affect the rate of postoperative complications. The exclusion of these variables in your study might have resulted in the underestimation or overestimation of the incidence of certain implant-related complications. For instance, patients with specific comorbidities might be more susceptible to particular complications, such as screw loosening or pull out, due to impaired bone healing. Likewise, certain surgical variables might elevate the risk of specific complications. For example, longer surgical duration and higher intraoperative blood loss could increase the risk of screw malposition due to surgeon fatigue and decreased concentration.

Another concern pertains to the identification of screw malposition as the most common implant-related complication. While your study mainly attributes this to factors such as the deep surgical field, degeneration, proximity to neurovascular tissue, and vertebrae with axial rotation, it overlooks the role of surgeon experience. The literature extensively documents that surgeon experience significantly influences the rate of screw malposition. For instance, a study by Gautschi et al. 4 suggests that less experienced surgeons have a higher rate of malpositioned screws compared to their more experienced peers. Moreover, a systematic review by Gelalis et al. 5 found that the accuracy of pedicle screw placement was significantly influenced by the surgeon’s experience and the utilization of advanced intraoperative imaging techniques. Thus, the omission of surgeon experience in your study may have led to an incomplete understanding of the factors contributing to screw malposition. In addition, the study by Gautschi et al. 6 emphasizes the importance of the learning curve in spinal surgery, indicating that the rate of complications, including screw malposition, significantly decreases after the surgeon has performed a certain number of procedures. This factor, not considered in your study, could provide further insights into the high incidence of screw malposition observed.

In conclusion, while your study offers valuable insights, considering comorbidities, surgical variables, surgeon experience, and the type of surgical instrumentation used may provide a more comprehensive understanding of implant-related complications in spinal fusion surgery.

Authors’ Note: All authors have completed and submitted the ICMJE disclosures form. The authors have no proprietary or commercial interest in any materials discussed in this article.
==== Refs
References

1 Koshimizu H Nakashima H Ohara T, et al. Implant-related complications after spinal fusion: a multicenter study. Global Spine J. 2024;14 (1 ):74-81. doi:10.1177/21925682221094267 35400240
2 Houten JK Weinstein GR Collins MJ Komlos D . Bilateral paraspinal muscle flap closure technique for reduction of wound complications from posterior thoracolumbar spinal fusion: results of a series of 716 patients. J Neurosurg Spine. 2020;34 (2 ):211-217. doi:10.3171/2020.6.SPINE20755 33065537
3 Rajaee SS Bae HW Kanim LE Delamarter RB . Spinal fusion in the United States: analysis of trends from 1998 to 2008. Spine. 2012;37 (1 ):67-76. doi:10.1097/BRS.0b013e31820cccfb 21311399
4 Gautschi OP Schatlo B Schaller K Tessitore E . Clinically relevant complications related to pedicle screw placement in thoracolumbar surgery and their management: a literature review of 35,630 pedicle screws. Neurosurg Focus. 2011;31 (4 ):E8. doi:10.3171/2011.7.FOCUS11168
5 Gelalis ID Paschos NK Pakos EE, et al. Accuracy of pedicle screw placement: a systematic review of prospective in vivo studies comparing free hand, fluoroscopy guidance and navigation techniques. Eur Spine J. 2012;21 (2 ):247-255. doi:10.1007/s00586-011-2011-3 21901328
6 Gautschi OP Schatlo B Schaller K Tessitore E . Clinically relevant complications related to pedicle screw placement in thoracolumbar surgery and their management: a literature review of 35,630 pedicle screws. Neurosurg Focus. 2011;31 (4 ):E8. doi:10.3171/2011.7.FOCUS11168
