Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Observational Study
. 2022 Dec;31(12):3544-3550.
doi: 10.1007/s00586-022-07427-0. Epub 2022 Oct 29.

Pedicle screw placement safety with the aid of patient-specific guides in a case series of patients with thoracic scoliosis

Janez Mohar  1   2 , Matej Valič  3 , Eva Podovšovnik  3 , Rene Mihalič  3   4
Affiliations
Observational Study

Pedicle screw placement safety with the aid of patient-specific guides in a case series of patients with thoracic scoliosis

Janez Mohar et al. Eur Spine J. 2022 Dec.

Abstract

Purpose: Pedicle screw (PS) placement in thoracic scoliotic deformities can be challenging due to altered vertebral anatomy; malposition can result in severe functional disability or inferior construct stability. Three-dimensional (3D) printed patient-specific guides (PSGs) have been recently used to supplement other PS placement techniques. We conducted a single-center, retrospective observational study to assess the accuracy of PS placement using PSGs in a consecutive case series of pediatric and adult patients with thoracic scoliosis.

Methods: We analyzed the data of patients with thoracic scoliosis who underwent PS placement using 3D-printed PSG as a vertebral cannulation aid between June 2013 and July 2018. PS positions were determined via Gertzbein-Robbins (GR) and Heary classifications on computed tomography images. We determined the concordance of actual and preoperatively planned PS positions and defined the technique learning curve using a receiver-operating characteristic (ROC) curve.

Results: We performed 362 thoracic PS placement procedures in 39 consecutive patients. We classified 352 (97.2%), 2 (0.6%), and 8 (2.2%) screws as GR grades 0 (optimal placement), I, and II, respectively. The average instrumented PS entry point offsets on the X- and Y-axes were both 0.8 mm, and the average differences in trajectory between the planned and the actual screw placements on the oblique sagittal and oblique transverse planes were 2.0° and 2.4°, respectively. The learning process was ongoing until the first 12 PSs were placed.

Conclusions: The accuracy of PS placement using patient-specific 3D templates in our case series exceeds the accuracies of established thoracic PS placement techniques.

Keywords: Patient-specific guides; Pedicle screw placement accuracy; Thoracic scoliosis; Three-dimensional printing.

PubMed Disclaimer

References

    1. Lenke LG, Kuklo TR, Ondra S, Polly DW (2008) Rationale behind the current state-of-the-art treatment of scoliosis (in the pedicle screw era). Spine 33:1051–1054. https://doi.org/10.1097/BRS.0b013e31816f2865 - DOI
    1. Davis CM, Grant CA, Pearcy MJ et al (2017) Is there asymmetry between the concave and convex pedicles in adolescent idiopathic scoliosis? A CT investigation. Clin Orthop Relat Res 475:884–893. https://doi.org/10.1007/s11999-016-5188-2 - DOI
    1. Hicks JM, Singla A, Shen FH, Arlet V (2010) Complications of pedicle screw fixation in scoliosis surgery: a systematic review. Spine 35:E465–E470. https://doi.org/10.1097/BRS.0b013e3181d1021a - DOI
    1. Tong Y, Kaplan DJ, Spivak JM, Bendo JA (2020) Three-dimensional printing in spine surgery: a review of current applications. Spine J 20:833–846. https://doi.org/10.1016/j.spinee.2019.11.004 - DOI
    1. Lopez CD, Boddapati V, Lee NJ et al (2021) Three-dimensional printing for preoperative planning and pedicle screw placement in adult spinal deformity: a systematic review. Glob Spine J 11:936–949. https://doi.org/10.1177/2192568220944170 - DOI

Publication types

LinkOut - more resources