Evidence map›Paper›PMID 40658701›Full record

ArticlePloS one2025

Investigating the relationship between internal spinal alignment and back shape in patients with scoliosis using PCdare: A comparative, reliability and validation study.

Mirko Kaiser, Meby Mudavamkunnel, Martin Bertsch, Christoph J Laux, Ines Unterfrauner, Florian Wanivenhaus, David E Bauer, Thorsten Jentzsch, Alexandra Stauffer, Mazda Farshad and 1 more

Abstract readValidation StudyComparative Study
In one paragraph

Article in PloS one, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

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3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

11 authors.

Mirko KaiserLaboratory for Movement Biomechanics, ETH Zurich, Switzerland.ORCID https://orcid.org/0000-0002-8763-5003
Meby MudavamkunnelLaboratory for Movement Biomechanics, ETH Zurich, Switzerland.ORCID https://orcid.org/0009-0004-2670-2657
Martin BertschLaboratory for Movement Biomechanics, ETH Zurich, Switzerland.
Christoph J LauxBalgrist University Hospital, University of Zurich, Switzerland.
Ines UnterfraunerBalgrist University Hospital, University of Zurich, Switzerland.
Florian WanivenhausBalgrist University Hospital, University of Zurich, Switzerland.
David E BauerBalgrist University Hospital, University of Zurich, Switzerland.
Thorsten JentzschBalgrist University Hospital, University of Zurich, Switzerland.
Alexandra StaufferBalgrist University Hospital, University of Zurich, Switzerland.
Mazda FarshadBalgrist University Hospital, University of Zurich, Switzerland.
Sasa CukovicLaboratory for Movement Biomechanics, ETH Zurich, Switzerland.ORCID https://orcid.org/0000-0003-0525-2197

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Optical 3D surface scanning has emerged as a valuable modality for assessing spinal deformity in patients with scoliosis, avoiding radiation exposure. However, correlations remain moderate between deformation parameters obtained from radiographs and those estimated solely from the 3D back surface, referred to as the "back-shape-to-spine" approach. To improve the accuracy with which the back-shape-to-spine approach can estimate the internal spinal alignment (ISL) from 3D surface scanning, deeper understanding is required of the effect of scoliosis on the back shape. The PCdare software, which enables semi-automatic registration of 3D surface scans with the corresponding biplanar radiographs, has been used by students in a previous study to validate study protocols, generate references for estimated ISL, and evaluate correlations between the spinous process line (SPL) and ISL. This study explored the potential of the PCdare software to investigate the underlying relationship between the ISL and the 3D back shape, conducted a comparative study with 3 study protocols, and conducted an inter- and intrarater reliability (IIR) study with 6 clinicians and 10 students as raters to evaluate the applicability of PCdare when used by students. The comparative study involved 252 patients with idiopathic scoliosis from 3 studies that compared the back-shape-to-spine approach with radiography. The quality of study protocols and the relationship between internal spinal alignment and 3D back shape were both investigated by evaluating the posture alignment errors and correlations between Cobb angles. The inter- and intrarater reliability study involved 7 patients with idiopathic scoliosis and was conducted using PCdare and validated with PACS. The median Cobb angle difference (interquartile range: IQR) between students and clinicians (interclass) was 0.06° (1.5°). The ICC [confidence interval] between Cobb angles (interrater) was 0.94 [0.7,0.98]. The median absolute Cobb angle difference (IQR) between 3 repetitions (intrarater) were 4.2° (5.3°) or lower. The median Cobb angle difference (IQR) between PCdare and PACS was 1.5° (8.4°) for clinicians and 1.4° (6.9°) for students, whereas the corresponding correlation [confidence interval] was 0.94 [0.92,0.96] and 0.95 [0.93,0.96], respectively. The median RMSE (median SD) of posture alignment error ranged between 8.1 mm (5.2 mm) and 5 mm (3.5 mm), whereas the median PCC (IQR) between ISL and SPL ranged between 0.64 (0.58) and 0.99 (0.02). Students achieve outcomes comparable to clinicians when using PCdare, which underlines its reliability and ease of use. In addition, the application of PCdare to examine the quality of study protocols revealed the necessity of markers and posture alignment and delivered correlation coefficients for the relationship between internal spinal alignment and 3D back shape. These findings highlight the potential of the PCdare software to advance the non-ionizing assessment of spinal deformities and thus improve understanding of scoliosis.

Indexed as

BackImaging, Three-DimensionalScoliosisSoftwareSpineAdolescentAdultChildFemaleHumansMaleRadiographyReproducibility of ResultsYoung Adult

Identifiers

PMID40658701
PMCPMC12258602

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.