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A simple method for assessing rotational flexibility in adolescent idiopathic scoliosis: modified Adam’s forward bending test

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Abstract

Purpose

This study aimed to evaluate the diagnostic aptitude of a modified Adams forward bending test (MAFBT), which addresses the coupling phenomenon of axial rotation with reference to the side-bending movement. Also, this evaluation was facilitated by the introduction of our rotational flexibility index (RFI).

Methods

Thirty-two female and eight male AIS patients were included in this study from a single institution. In the MAFBT, subjects were asked to bend to the convex side of the curve in the forward bending position. Scoliometric measurements were done during the AFBT and MAFBT. Utilizing anteroposterior standing plain radiographs curve flexibility indices were calculated. The diagnostic aptitude of the MAFBT was evaluated based on the receiver operating characteristic (ROC) curves and area under the curve (AUC). The RFI was also assessed, which considered AFBT and MAFBT parameters as a specified function.

Results

Significant correlations were noted between the Cobb angle and AFBT (p = 0.005), fulcrum bending and the MAFBT (p = 0.0001), side-bending and MAFBT (p = 0.0001). There were significant positive correlations between rotational flexibility as based on fulcrum bending radiograph to that of the RFI (r = 0.4, p = 0.036) and side-bending technique (r = 0.4, p = 0.008). Based on ROC analyses (AUC range 0.7–0.8), the MAFBT demonstrated high specificity and sensitivity rates for flexible and rigid curves, respectively.

Conclusions

This is the first study to report that the MAFBT is a simple and reliable test for the clinical assessment of rotational flexibility in AIS patients. The study further noted that the novel RFI has clinical utility in the assessment of AIS.

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Funding

No funding was received for this work.

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Authors and Affiliations

Authors

Contributions

All authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by AS, MNI, NA, DS and KDKL. The first draft of the manuscript was written by AS and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.

Corresponding author

Correspondence to Alpaslan Senkoylu.

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Conflict of interest

The authors have no financial or competing interests in relation to this work.

IRB approval

Gazi University does not oblige us to an IRB approval for non-invasive cross-sectional descriptive studies. Thus, we currently don't have an approval from our institution for the work. As you may already aware of from the abstract, this valuable study aimed to validate a physical examination method.

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Senkoylu, A., Ilhan, M.N., Altun, N. et al. A simple method for assessing rotational flexibility in adolescent idiopathic scoliosis: modified Adam’s forward bending test. Spine Deform 9, 333–339 (2021). https://doi.org/10.1007/s43390-020-00221-2

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  • DOI: https://doi.org/10.1007/s43390-020-00221-2

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